use anyhow::{bail, Context, Result};
use chrono::Utc;
use clap::Parser;
use once_cell::sync::Lazy;
use rayon::prelude::*;
use regex::Regex;
use serde::{Deserialize, Serialize};
use serde_json::{json, Value};
use std::collections::{HashMap, HashSet};
use std::fs::{self, File};
use std::io::{BufRead, BufReader, BufWriter, Write};
use std::path::PathBuf;
use std::sync::atomic::{AtomicUsize, Ordering};

#[derive(Parser, Debug)]
#[command(about = "Apply DMHY template recipes with a multi-core Rust pipeline")]
struct Args {
    #[arg(long)]
    cluster: bool,
    #[arg(long)]
    audit_low_frequency: bool,
    #[arg(long)]
    verify_generated_output: bool,
    #[arg(long, default_value = "datasets/AnimeName/dmhy_list.jsonl")]
    input: PathBuf,
    #[arg(long, default_value = "reports/dmhy_template_recipes.seed.jsonl")]
    recipes: PathBuf,
    #[arg(
        long,
        default_value = "reports/dmhy_weak.template_generated.rust.jsonl"
    )]
    output: PathBuf,
    #[arg(
        long,
        default_value = "reports/dmhy_weak.template_generated.rust.manifest.json"
    )]
    manifest_output: PathBuf,
    #[arg(
        long,
        default_value = "reports/dmhy_template_clusters.rust.summary.json"
    )]
    summary_output: PathBuf,
    #[arg(
        long,
        default_value = "reports/dmhy_template_clusters.rust.samples.jsonl"
    )]
    samples_output: PathBuf,
    #[arg(long, default_value = "reports/dmhy_template_clusters.rust.jsonl")]
    clusters_output: PathBuf,
    #[arg(long, default_value = "reports/dmhy_template_recipes.rust.seed.jsonl")]
    recipes_output: PathBuf,
    #[arg(long, default_value = "reports/dmhy_template_review.rust.jsonl")]
    review_output: PathBuf,
    #[arg(long, default_value = "reports/dmhy_low_frequency_audit.rust.jsonl")]
    audit_output: PathBuf,
    #[arg(long, default_value_t = 50)]
    audit_max_count: u64,
    #[arg(long)]
    limit: Option<usize>,
    #[arg(long)]
    limit_templates: Option<usize>,
    #[arg(long, default_value_t = 1)]
    min_count: u64,
    #[arg(long, default_value_t = 200)]
    top: usize,
    #[arg(long, default_value_t = 200)]
    recipe_top: usize,
    #[arg(long, default_value_t = 1000)]
    review_top: usize,
    #[arg(long, default_value_t = 8)]
    examples: usize,
    #[arg(long, default_value_t = 25)]
    recipe_min_count: usize,
    #[arg(long, default_value = "high")]
    confidence: String,
    #[arg(long, default_value = "all")]
    expand: String,
    #[arg(long, default_value_t = 100)]
    sample_per_template: usize,
    #[arg(long)]
    keep_encoding_noise: bool,
    #[arg(long)]
    preserve_parent_paths: bool,
    #[arg(long)]
    threads: Option<usize>,
}

#[derive(Debug, Clone, Deserialize)]
struct Recipe {
    template_id: String,
    template: String,
    roles: Vec<String>,
    confidence: Option<String>,
    count: Option<u64>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
struct Record {
    filename: String,
    tokens: Vec<String>,
    labels: Vec<String>,
    template_id: String,
    template: String,
    #[serde(skip_serializing_if = "Option::is_none")]
    source_filename: Option<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    path_trimmed: Option<bool>,
    #[serde(skip_serializing_if = "Option::is_none")]
    dropped_title_candidate_positions: Option<Vec<String>>,
}

#[derive(Debug, Clone)]
struct Group {
    indices: Vec<usize>,
    class_name: String,
}

#[derive(Debug, Default, Clone, Serialize)]
struct Stats {
    seen: usize,
    skipped_encoding_noise: usize,
    trimmed_parent_path: usize,
    skipped_no_recipe: usize,
    skipped_sample_cap: usize,
    skipped_role_mismatch: usize,
    skipped_low_frequency_audit_warning: usize,
    written: usize,
}

#[derive(Debug, Default)]
struct Cluster {
    count: usize,
    examples: Vec<String>,
    literal_counts: HashMap<String, usize>,
    class_counts: HashMap<String, usize>,
    position_literals: Vec<HashMap<String, usize>>,
}

#[derive(Debug)]
enum Processed {
    Written {
        record: Record,
        trimmed_parent: bool,
    },
    Skipped {
        reason: &'static str,
        trimmed_parent: bool,
    },
}

static HASH_RE: Lazy<Regex> = Lazy::new(|| Regex::new(r"^[A-Fa-f0-9]{8,}$").unwrap());
static RESOLUTION_RE: Lazy<Regex> =
    Lazy::new(|| Regex::new(r"(?i)^(?:\d{3,4}p|\dK|\d{3,4}[xX×]\d{3,4})$").unwrap());
static EPISODE_VERSION_RE: Lazy<Regex> =
    Lazy::new(|| Regex::new(r"(?i)^(?:EP?)?\d{1,4}(?:v|ver|version|rev)\d{1,3}$").unwrap());
static EPISODE_RE: Lazy<Regex> =
    Lazy::new(|| Regex::new(r"(?i)^(?:EP?|#)?\d{1,4}(?:END)?$").unwrap());
static EPISODE_CJK_RE: Lazy<Regex> = Lazy::new(|| Regex::new(r"^第?\d{1,4}[话話回集]$").unwrap());
static EPISODE_RANGE_RE: Lazy<Regex> =
    Lazy::new(|| Regex::new(r"(?i)^\d{1,4}\s*[-~]\s*\d{1,4}(?:\s*END)?$").unwrap());
static EPISODE_BATCH_RE: Lazy<Regex> = Lazy::new(|| {
    Regex::new(r"(?i)^\d{1,4}\s*[-~]\s*\d{1,4}(?:\s*(?:TV|全集|全|END|Fin|Complete|SP|OVA|OAD|NCOP|NCED)|[+_./-])*.{0,16}$").unwrap()
});
static SXE_RE: Lazy<Regex> = Lazy::new(|| Regex::new(r"(?i)^S\d{1,2}E\d{1,4}(?:v\d+)?$").unwrap());
static SXE_VALUE_RE: Lazy<Regex> =
    Lazy::new(|| Regex::new(r"(?i)^S(\d{1,2})E(\d{1,4})(?:v(\d+))?$").unwrap());
static EPISODE_VALUE_RE: Lazy<Regex> =
    Lazy::new(|| Regex::new(r"(?i)^(EP|E|#)(\d{1,4})(?:v(\d+))?$").unwrap());
static SEASON_RE: Lazy<Regex> = Lazy::new(|| {
    Regex::new(r"(?i)^(?:S\d{1,2}|Season\s*\d{1,2}|第[一二三四五六七八九十\d]+[季期部])$").unwrap()
});
static CJK_SEASON_TOKEN_RE: Lazy<Regex> =
    Lazy::new(|| Regex::new(r"^第[一二三四五六七八九十\d]+[季期部]$").unwrap());
static SEASON_VALUE_RE: Lazy<Regex> = Lazy::new(|| Regex::new(r"(?i)^S(\d{1,2})$").unwrap());
static SPECIAL_RE: Lazy<Regex> = Lazy::new(|| {
    Regex::new(r"(?i)^(?:NCOP|NCED|OP|ED|PV|CM|SP|OVA|OAD|IV|Menu|Intro|Preview|Trailer|Teaser|Animatics?)(?:[\s_.-]?(?:\d{0,4}|Ep\d{1,4}|[A-Z]))?$").unwrap()
});
static VOLUME_RE: Lazy<Regex> =
    Lazy::new(|| Regex::new(r"(?i)^(?:Vol(?:ume)?\.?|Disc|CD|BD|DVD|D)\s*\d{1,3}$").unwrap());
static DATE_RE: Lazy<Regex> =
    Lazy::new(|| Regex::new(r"^(?:19|20)\d{2}(?:[._-]\d{1,2}){0,2}$").unwrap());
static LANG_RE: Lazy<Regex> = Lazy::new(|| {
    Regex::new(r"(?i)^(?:CHS|CHT|ZHS|ZHT|GB|BIG5|JPN?|JP|JA|JAP|ENG|EN|SC|TC|简[体體]?|繁[体體]?|简日|繁日|字幕|内封|外挂|Sub|Subs|MSubs?)$").unwrap()
});
static MEDIA_RE: Lazy<Regex> = Lazy::new(|| {
    Regex::new(r"(?i)^(?:WEB[-_. ]?DL|WEB[-_. ]?Rip|BDRip|BluRay|BDMV|BD|DVDRip|DVD|HDTV|TVRip|REMUX|x26[45]|h\.?26[45]|HEVC|AVC|AV1|AAC\d*(?:\.\d+)?|FLAC|MP3|DTS|DTS-HDMA|AC3|Opus|10[-_. ]?bit|8[-_. ]?bit|Hi10p|Ma10p|ASSx?\d*|SRTx?\d*|R\d[A-Z]*|NoSub|MKV|MP4|AVI|RAW|Raws?)$").unwrap()
});
static SPECIAL_TITLE_PHRASE_RE: Lazy<Regex> = Lazy::new(|| {
    Regex::new(r"(?i)\b(?:theater\s+greeting\s+event|world\s+prem(?:eie|iere)|picture\s+drama)\b")
        .unwrap()
});
static YEAR_RANGE_RE: Lazy<Regex> =
    Lazy::new(|| Regex::new(r"^\(?\s*(?:19|20)\d{2}\s*[-~]\s*(?:19|20)\d{2}\s*\)?$").unwrap());
static PATH_SEGMENT_SEASON_RE: Lazy<Regex> = Lazy::new(|| {
    Regex::new(r"(?i)(?:^|[\s_.\-/])(?:season\s*\d{1,2}|s\d{1,2})(?:$|[\s_.\-/])").unwrap()
});
static SEASON_WORD_NUMBER_RE: Lazy<Regex> =
    Lazy::new(|| Regex::new(r"(?i)(?:season|saison)\s*0?(\d{1,2})").unwrap());
static PLAIN_SEASON_SEGMENT_RE: Lazy<Regex> =
    Lazy::new(|| Regex::new(r"(?i)^(?:season|saison)\s*0?\d{1,2}$|^s0?\d{1,2}$").unwrap());
static S_NUMBER_SEGMENT_RE: Lazy<Regex> =
    Lazy::new(|| Regex::new(r"(?i)(?:^|[^\p{L}\p{N}])s0?(\d{1,2})(?:$|[^\p{L}\p{N}])").unwrap());
static SXE_SEASON_RE: Lazy<Regex> = Lazy::new(|| {
    Regex::new(r"(?i)(?:^|[^\p{L}\p{N}])s0?(\d{1,2})e\d{1,4}(?:$|[^\p{L}\p{N}])").unwrap()
});
static TOKEN_REGEXES: Lazy<Vec<Regex>> = Lazy::new(|| {
    [
        r"^\d{3,4}[xX×]\d{3,4}",
        r"(?i)^h\.?26[45]",
        r"(?i)^x\.?26[45]",
        r"^[\\/]+",
        r"^[-_.:：+&|]+",
        r"^\s+",
        r"(?i)^Season\s*\d{1,2}",
        r"^[A-Za-z]+(?:\d+[A-Za-z]*)*",
        r"^\d+[A-Za-z]+\d*",
        r"^\d{1,4}(?:[._-]\d{1,4})*",
        r"^[\p{Hiragana}\p{Katakana}\p{Han}]+",
    ]
    .into_iter()
    .map(|pattern| Regex::new(pattern).unwrap())
    .collect()
});
static SIMPLE_EPISODE_RE: Lazy<Regex> =
    Lazy::new(|| Regex::new(r"(?i)^(?:EP?|#)?\d{1,4}$").unwrap());
static SPECIAL_SPACE_RE: Lazy<Regex> = Lazy::new(|| Regex::new(r"[\s_.-]+").unwrap());

fn main() -> Result<()> {
    let args = Args::parse();
    if let Some(threads) = args.threads {
        rayon::ThreadPoolBuilder::new()
            .num_threads(threads)
            .build_global()
            .context("failed to configure rayon thread pool")?;
    }
    if args.cluster {
        return run_cluster(&args);
    }
    if args.audit_low_frequency {
        return run_low_frequency_audit(&args);
    }
    if args.verify_generated_output {
        return run_verify_generated_output(&args);
    }
    if args.expand != "all" && args.expand != "sample" {
        bail!("--expand must be all or sample");
    }

    let recipes = load_recipes(&args)?;
    if recipes.is_empty() {
        bail!("no recipes selected; adjust --recipes/--confidence/--min-count/--limit-templates");
    }
    let inputs = load_input(&args.input, args.limit)?;
    let sample_counters: HashMap<String, AtomicUsize> = recipes
        .values()
        .map(|recipe| (recipe.template_id.clone(), AtomicUsize::new(0)))
        .collect();

    let processed: Vec<Processed> = inputs
        .par_iter()
        .map(|filename| process_filename(filename, &args, &recipes, &sample_counters))
        .collect();

    if let Some(parent) = args.output.parent() {
        fs::create_dir_all(parent)?;
    }
    if let Some(parent) = args.manifest_output.parent() {
        fs::create_dir_all(parent)?;
    }

    let mut stats = Stats {
        seen: inputs.len(),
        ..Stats::default()
    };
    let mut label_counts: HashMap<String, usize> = HashMap::new();
    let mut template_counts: HashMap<String, usize> = HashMap::new();
    let mut examples = Vec::new();
    let mut writer = BufWriter::new(File::create(&args.output)?);
    for item in processed {
        match item {
            Processed::Written {
                record,
                trimmed_parent,
            } => {
                if trimmed_parent {
                    stats.trimmed_parent_path += 1;
                }
                for label in &record.labels {
                    *label_counts.entry(label.clone()).or_default() += 1;
                }
                *template_counts
                    .entry(record.template_id.clone())
                    .or_default() += 1;
                if examples.len() < 20 {
                    examples.push(serde_json::to_value(&record)?);
                }
                serde_json::to_writer(&mut writer, &record)?;
                writer.write_all(b"\n")?;
                stats.written += 1;
            }
            Processed::Skipped {
                reason,
                trimmed_parent,
            } => {
                if trimmed_parent {
                    stats.trimmed_parent_path += 1;
                }
                match reason {
                    "encoding_noise" => stats.skipped_encoding_noise += 1,
                    "no_recipe" => stats.skipped_no_recipe += 1,
                    "sample_cap" => stats.skipped_sample_cap += 1,
                    "role_mismatch" => stats.skipped_role_mismatch += 1,
                    "low_frequency_audit_warning" => {
                        stats.skipped_low_frequency_audit_warning += 1
                    }
                    _ => {}
                }
            }
        }
    }
    writer.flush()?;

    let mut top_template_counts: Vec<_> = template_counts.into_iter().collect();
    top_template_counts.sort_by(|a, b| b.1.cmp(&a.1).then_with(|| a.0.cmp(&b.0)));
    top_template_counts.truncate(20);

    let manifest = json!({
        "generated_at": Utc::now().to_rfc3339(),
        "input": args.input.to_string_lossy(),
        "recipes": args.recipes.to_string_lossy(),
        "output": args.output.to_string_lossy(),
        "selected_templates": recipes.len(),
        "confidence": args.confidence,
        "min_count": args.min_count,
        "low_frequency_audit_max_count": args.audit_max_count,
        "low_frequency_blocking_warnings": [
            "hash_labeled",
            "multiple_title_spans",
            "no_title",
            "path_retained"
        ],
        "expand": args.expand,
        "sample_per_template": if args.expand == "sample" { Some(args.sample_per_template) } else { None },
        "stats": stats,
        "label_counts": label_counts,
        "top_template_counts": top_template_counts,
        "examples": examples,
        "implementation": "rust_dmhy_template_apply"
    });
    fs::write(
        &args.manifest_output,
        serde_json::to_string_pretty(&manifest)?,
    )?;
    println!("{}", serde_json::to_string_pretty(&manifest)?);
    Ok(())
}

fn load_recipes(args: &Args) -> Result<HashMap<String, Recipe>> {
    let file = File::open(&args.recipes)
        .with_context(|| format!("recipe JSONL not found: {}", args.recipes.display()))?;
    let mut recipes = HashMap::new();
    for (line_number, line) in BufReader::new(file).lines().enumerate() {
        let line = line?;
        if line.trim().is_empty() {
            continue;
        }
        let row: Recipe = serde_json::from_str(&line).with_context(|| {
            format!(
                "invalid recipe JSON at {}:{}",
                args.recipes.display(),
                line_number + 1
            )
        })?;
        if !args.confidence.is_empty()
            && row.confidence.as_deref() != Some(args.confidence.as_str())
        {
            continue;
        }
        if row.count.unwrap_or(0) < args.min_count {
            continue;
        }
        recipes.insert(row.template.clone(), row);
        if args
            .limit_templates
            .is_some_and(|limit| recipes.len() >= limit)
        {
            break;
        }
    }
    Ok(recipes)
}

fn load_input(path: &PathBuf, limit: Option<usize>) -> Result<Vec<String>> {
    let file =
        File::open(path).with_context(|| format!("input JSONL not found: {}", path.display()))?;
    let mut values = Vec::new();
    for (line_number, line) in BufReader::new(file).lines().enumerate() {
        if limit.is_some_and(|limit| values.len() >= limit) {
            break;
        }
        let line = line?;
        if line.trim().is_empty() {
            continue;
        }
        let row: Value = serde_json::from_str(&line)
            .with_context(|| format!("invalid JSON at {}:{}", path.display(), line_number + 1))?;
        if let Some(value) = row.get("value").and_then(Value::as_str) {
            let value = value.trim();
            if !value.is_empty() {
                values.push(value.to_string());
            }
        }
    }
    Ok(values)
}

fn run_cluster(args: &Args) -> Result<()> {
    let inputs = load_input(&args.input, args.limit)?;
    let source_rows = inputs.len();
    let mut clusters: HashMap<String, Cluster> = HashMap::new();
    let mut skipped_encoding_noise = 0usize;
    let mut trimmed_parent_path = 0usize;
    let mut total_rows = 0usize;

    for original in inputs {
        if !args.keep_encoding_noise
            && (has_encoding_noise(&original)
                || has_non_anime_noise(&original)
                || has_abstract_path_noise(&original))
        {
            skipped_encoding_noise += 1;
            continue;
        }
        let filename = if args.preserve_parent_paths {
            original
        } else {
            let (training_filename, was_trimmed) = training_filename_for(&original);
            if was_trimmed {
                trimmed_parent_path += 1;
            }
            training_filename
        };
        add_cluster(&mut clusters, &filename, args.examples);
        total_rows += 1;
    }

    let mut sorted_clusters: Vec<_> = clusters.into_iter().collect();
    sorted_clusters.sort_by(|a, b| b.1.count.cmp(&a.1.count).then_with(|| a.0.cmp(&b.0)));

    let cluster_rows: Vec<Value> = sorted_clusters
        .iter()
        .enumerate()
        .map(|(index, (key, cluster))| cluster_row(index + 1, key, cluster, total_rows))
        .collect();
    let samples: Vec<Value> = cluster_rows.iter().take(args.top).cloned().collect();
    let recipe_candidates: Vec<Value> =
        cluster_rows.iter().take(args.recipe_top).cloned().collect();
    let recipes: Vec<Value> = recipe_candidates
        .iter()
        .filter(|row| is_high_confidence_recipe(row, args.recipe_min_count))
        .map(|row| recipe_row(row, "high"))
        .collect();
    let review: Vec<Value> = recipe_candidates
        .iter()
        .filter(|row| !is_high_confidence_recipe(row, args.recipe_min_count))
        .take(args.review_top)
        .cloned()
        .collect();

    write_jsonl_values(&args.clusters_output, &cluster_rows)?;
    write_jsonl_values(&args.samples_output, &samples)?;
    write_jsonl_values(&args.recipes_output, &recipes)?;
    write_jsonl_values(&args.review_output, &review)?;

    let mut histogram: HashMap<usize, usize> = HashMap::new();
    for (_, cluster) in &sorted_clusters {
        *histogram.entry(cluster.count).or_default() += 1;
    }
    let mut count_histogram_top: Vec<_> = histogram.into_iter().collect();
    count_histogram_top.sort_by(|a, b| b.1.cmp(&a.1).then_with(|| a.0.cmp(&b.0)));
    count_histogram_top.truncate(20);

    let rows_covered_by_repeated_templates: usize = sorted_clusters
        .iter()
        .map(|(_, cluster)| cluster)
        .filter(|cluster| cluster.count as u64 >= args.min_count)
        .map(|cluster| cluster.count)
        .sum();
    let templates_at_least_min_count = sorted_clusters
        .iter()
        .filter(|(_, cluster)| cluster.count as u64 >= args.min_count)
        .count();
    let top_templates: Vec<Value> = cluster_rows.iter().take(20).cloned().collect();
    let summary = json!({
        "input": args.input.to_string_lossy(),
        "source_rows": source_rows,
        "skipped_encoding_noise": skipped_encoding_noise,
        "trimmed_parent_path": trimmed_parent_path,
        "total_rows": total_rows,
        "unique_templates": sorted_clusters.len(),
        "min_count": args.min_count,
        "templates_at_least_min_count": templates_at_least_min_count,
        "rows_covered_by_repeated_templates": rows_covered_by_repeated_templates,
        "rows_covered_by_repeated_templates_ratio": if total_rows == 0 { 0.0 } else { rows_covered_by_repeated_templates as f64 / total_rows as f64 },
        "top_output_rows": samples.len(),
        "clusters_output": args.clusters_output.to_string_lossy(),
        "cluster_rows": cluster_rows.len(),
        "recipes_output": args.recipes_output.to_string_lossy(),
        "recipe_rows": recipes.len(),
        "review_output": args.review_output.to_string_lossy(),
        "review_rows": review.len(),
        "recipe_top": args.recipe_top,
        "recipe_min_count": args.recipe_min_count,
        "top_templates": top_templates,
        "count_histogram_top": count_histogram_top,
        "implementation": "rust_dmhy_template_cluster",
        "generated_at": Utc::now().to_rfc3339(),
    });
    if let Some(parent) = args.summary_output.parent() {
        fs::create_dir_all(parent)?;
    }
    fs::write(
        &args.summary_output,
        serde_json::to_string_pretty(&summary)?,
    )?;
    println!("{}", serde_json::to_string_pretty(&summary)?);
    Ok(())
}

fn add_cluster(clusters: &mut HashMap<String, Cluster>, filename: &str, example_limit: usize) {
    let (key, tokens, classes, groups) = template_key_for_filename(filename);
    let cluster = clusters.entry(key).or_default();
    cluster.count += 1;
    if cluster.examples.len() < example_limit {
        cluster.examples.push(filename.to_string());
    }
    for (token, class_name) in tokens.iter().zip(classes.iter()) {
        *cluster.class_counts.entry(class_name.clone()).or_default() += 1;
        if matches!(class_name.as_str(), "TEXT" | "BRACKET_TEXT") {
            let cleaned = strip_wrapper(token);
            if !cleaned.is_empty() {
                *cluster.literal_counts.entry(cleaned).or_default() += 1;
            }
        }
    }
    while cluster.position_literals.len() < groups.len() {
        cluster.position_literals.push(HashMap::new());
    }
    for (index, group) in groups.iter().enumerate() {
        if matches!(group.class_name.as_str(), "TEXT" | "BRACKET_TEXT") {
            let text = group_text(&tokens, group);
            if !text.is_empty() {
                *cluster.position_literals[index].entry(text).or_default() += 1;
            }
        }
    }
}

fn cluster_row(rank: usize, key: &str, cluster: &Cluster, total: usize) -> Value {
    json!({
        "template_id": format!("tpl_{rank:06}"),
        "template": key,
        "count": cluster.count,
        "coverage": if total == 0 { 0.0 } else { cluster.count as f64 / total as f64 },
        "top_literals": top_counts(&cluster.literal_counts, 12),
        "suggested_roles": suggested_roles(key),
        "position_top_literals": cluster.position_literals.iter().map(|counts| top_counts(counts, 5)).collect::<Vec<_>>(),
        "class_counts": top_counts(&cluster.class_counts, 20),
        "examples": cluster.examples,
    })
}

fn top_counts(counts: &HashMap<String, usize>, limit: usize) -> Vec<(String, usize)> {
    let mut items: Vec<_> = counts
        .iter()
        .map(|(key, count)| (key.clone(), *count))
        .collect();
    items.sort_by(|a, b| b.1.cmp(&a.1).then_with(|| a.0.cmp(&b.0)));
    items.truncate(limit);
    items
}

fn is_high_confidence_recipe(row: &Value, min_count: usize) -> bool {
    if row.get("count").and_then(Value::as_u64).unwrap_or(0) < min_count as u64 {
        return false;
    }
    let roles = match row.get("suggested_roles").and_then(Value::as_array) {
        Some(roles) => roles,
        None => return false,
    };
    let role_strings: Vec<&str> = roles.iter().filter_map(Value::as_str).collect();
    if role_strings.iter().any(|role| role.contains("_OR_")) {
        return false;
    }
    if !role_strings.contains(&"TITLE")
        || !role_strings.iter().any(|role| {
            role.starts_with("EPISODE") || matches!(*role, "SPECIAL" | "SOURCE" | "RESOLUTION")
        })
    {
        return false;
    }
    let template = row.get("template").and_then(Value::as_str).unwrap_or("");
    if template.contains("BRACKET_TEXT BRACKET_TEXT") && !role_strings.contains(&"GROUP") {
        return false;
    }
    !role_strings.contains(&"TITLE_OR_TEXT")
}

fn recipe_row(row: &Value, confidence: &str) -> Value {
    json!({
        "template_id": row["template_id"],
        "template": row["template"],
        "roles": row["suggested_roles"],
        "confidence": confidence,
        "count": row["count"],
        "examples": row["examples"],
    })
}

fn write_jsonl_values(path: &PathBuf, rows: &[Value]) -> Result<()> {
    if let Some(parent) = path.parent() {
        fs::create_dir_all(parent)?;
    }
    let mut writer = BufWriter::new(File::create(path)?);
    for row in rows {
        serde_json::to_writer(&mut writer, row)?;
        writer.write_all(b"\n")?;
    }
    writer.flush()?;
    Ok(())
}

fn run_low_frequency_audit(args: &Args) -> Result<()> {
    let recipes = load_recipes(args)?;
    let inputs = load_input(&args.input, args.limit)?;
    let low_template_total = recipes
        .values()
        .filter(|recipe| recipe.count.unwrap_or(0) <= args.audit_max_count)
        .count();
    let mut seen_templates = HashSet::new();
    let mut rows = Vec::new();

    for original in inputs {
        if !args.keep_encoding_noise
            && (has_encoding_noise(&original)
                || has_non_anime_noise(&original)
                || has_abstract_path_noise(&original))
        {
            continue;
        }
        let (training_filename, trimmed_parent) = training_filename_for(&original);
        let (key, _tokens, _classes, groups) = template_key_for_filename(&training_filename);
        let Some(recipe) = recipes.get(&key) else {
            continue;
        };
        let count = recipe.count.unwrap_or(0);
        if count > args.audit_max_count || !seen_templates.insert(recipe.template_id.clone()) {
            continue;
        }
        if recipe.roles.len() != groups.len() {
            continue;
        }
        let Some(mut record) = dmhy_record(&training_filename, &recipe.template_id, &recipe.roles)
        else {
            continue;
        };
        if trimmed_parent {
            record.source_filename = Some(original.clone());
            record.path_trimmed = Some(true);
        }
        rows.push(json!({
            "template_id": recipe.template_id,
            "count": count,
            "template": recipe.template,
            "filename": record.filename,
            "source_filename": record.source_filename,
            "path_trimmed": record.path_trimmed.unwrap_or(false),
            "spans": entity_spans(&record.tokens, &record.labels),
            "warnings": audit_warnings(&record),
            "tokens": record.tokens,
            "labels": record.labels,
        }));
        if seen_templates.len() >= low_template_total {
            break;
        }
    }

    rows.sort_by(|a, b| {
        let count_a = a.get("count").and_then(Value::as_u64).unwrap_or(0);
        let count_b = b.get("count").and_then(Value::as_u64).unwrap_or(0);
        let id_a = a.get("template_id").and_then(Value::as_str).unwrap_or("");
        let id_b = b.get("template_id").and_then(Value::as_str).unwrap_or("");
        count_a.cmp(&count_b).then_with(|| id_a.cmp(id_b))
    });
    write_jsonl_values(&args.audit_output, &rows)?;
    let warning_counts = warning_counts(&rows);
    let manifest = json!({
        "generated_at": Utc::now().to_rfc3339(),
        "input": args.input.to_string_lossy(),
        "recipes": args.recipes.to_string_lossy(),
        "audit_output": args.audit_output.to_string_lossy(),
        "audit_max_count": args.audit_max_count,
        "low_template_total": low_template_total,
        "audited_templates": rows.len(),
        "warning_counts": warning_counts,
        "implementation": "rust_dmhy_low_frequency_audit"
    });
    println!("{}", serde_json::to_string_pretty(&manifest)?);
    Ok(())
}

fn run_verify_generated_output(args: &Args) -> Result<()> {
    let file = File::open(&args.input)
        .with_context(|| format!("generated JSONL not found: {}", args.input.display()))?;
    let recipes_by_id: HashMap<String, u64> = load_recipes(args)?
        .into_values()
        .map(|recipe| (recipe.template_id, recipe.count.unwrap_or(0)))
        .collect();
    let mut rows = 0usize;
    let mut low_frequency_rows = 0usize;
    let mut warning_counts: HashMap<String, usize> = HashMap::new();
    let mut examples: HashMap<String, Vec<Value>> = HashMap::new();

    for (line_number, line) in BufReader::new(file).lines().enumerate() {
        let line = line?;
        if line.trim().is_empty() {
            continue;
        }
        let record: Record = serde_json::from_str(&line).with_context(|| {
            format!(
                "invalid generated record at {}:{}",
                args.input.display(),
                line_number + 1
            )
        })?;
        rows += 1;
        let count = recipes_by_id
            .get(&record.template_id)
            .copied()
            .unwrap_or(u64::MAX);
        if count > args.audit_max_count {
            continue;
        }
        low_frequency_rows += 1;
        for warning in audit_warnings(&record) {
            if !matches!(
                warning.as_str(),
                "hash_labeled" | "multiple_title_spans" | "no_title" | "path_retained"
            ) {
                continue;
            }
            *warning_counts.entry(warning.clone()).or_default() += 1;
            let bucket = examples.entry(warning).or_default();
            if bucket.len() < 5 {
                bucket.push(json!({
                    "template_id": record.template_id,
                    "template_count": count,
                    "filename": record.filename,
                    "spans": entity_spans(&record.tokens, &record.labels),
                }));
            }
        }
    }

    let manifest = json!({
        "generated_at": Utc::now().to_rfc3339(),
        "input": args.input.to_string_lossy(),
        "recipes": args.recipes.to_string_lossy(),
        "audit_max_count": args.audit_max_count,
        "rows": rows,
        "low_frequency_rows": low_frequency_rows,
        "blocking_warning_counts": warning_counts,
        "examples": examples,
        "implementation": "rust_dmhy_generated_output_verify"
    });
    println!("{}", serde_json::to_string_pretty(&manifest)?);
    if !warning_counts.is_empty() {
        bail!("generated output still has low-frequency blocking warnings");
    }
    Ok(())
}

fn entity_spans(tokens: &[String], labels: &[String]) -> Vec<Value> {
    let mut spans = Vec::new();
    let mut current_label: Option<String> = None;
    let mut current_text = String::new();
    for (token, label) in tokens.iter().zip(labels.iter()) {
        let entity = label
            .strip_prefix("B-")
            .or_else(|| label.strip_prefix("I-"))
            .unwrap_or("O");
        if current_label.as_deref() == Some(entity) {
            current_text.push_str(token);
            continue;
        }
        if let Some(label) = current_label.take() {
            if label != "O" {
                spans.push(json!({ "label": label, "text": current_text }));
            }
        }
        current_label = Some(entity.to_string());
        current_text = token.clone();
    }
    if let Some(label) = current_label {
        if label != "O" {
            spans.push(json!({ "label": label, "text": current_text }));
        }
    }
    spans
}

fn audit_warnings(record: &Record) -> Vec<String> {
    let mut warnings = Vec::new();
    let title_spans = entity_spans(&record.tokens, &record.labels)
        .into_iter()
        .filter(|span| span.get("label").and_then(Value::as_str) == Some("TITLE"))
        .count();
    if title_spans == 0 {
        warnings.push("no_title".to_string());
    } else if title_spans > 1 {
        warnings.push("multiple_title_spans".to_string());
    }
    if !record.labels.iter().any(|label| label.ends_with("EPISODE")) {
        warnings.push("no_episode".to_string());
    }
    if record.filename.contains('/') || record.filename.contains('\\') {
        warnings.push("path_retained".to_string());
    }
    for (index, token) in record.tokens.iter().enumerate() {
        if HASH_RE.is_match(token) && record.labels.get(index).is_some_and(|label| label != "O") {
            warnings.push("hash_labeled".to_string());
            break;
        }
    }
    warnings.sort();
    warnings.dedup();
    warnings
}

fn warning_counts(rows: &[Value]) -> HashMap<String, usize> {
    let mut counts = HashMap::new();
    for row in rows {
        if let Some(warnings) = row.get("warnings").and_then(Value::as_array) {
            for warning in warnings {
                if let Some(warning) = warning.as_str() {
                    *counts.entry(warning.to_string()).or_default() += 1;
                }
            }
        }
    }
    counts
}

fn process_filename(
    original: &str,
    args: &Args,
    recipes: &HashMap<String, Recipe>,
    sample_counters: &HashMap<String, AtomicUsize>,
) -> Processed {
    if !args.keep_encoding_noise
        && (has_encoding_noise(original)
            || has_non_anime_noise(original)
            || has_abstract_path_noise(original))
    {
        return Processed::Skipped {
            reason: "encoding_noise",
            trimmed_parent: false,
        };
    }
    let (training_filename, trimmed_parent) = training_filename_for(original);
    let (key, _tokens, _classes, groups) = template_key_for_filename(&training_filename);
    let recipe = match recipes.get(&key) {
        Some(recipe) => recipe,
        None => {
            return Processed::Skipped {
                reason: "no_recipe",
                trimmed_parent,
            }
        }
    };
    if args.expand == "sample" {
        let counter = sample_counters.get(&recipe.template_id).unwrap();
        if counter.fetch_add(1, Ordering::Relaxed) >= args.sample_per_template {
            return Processed::Skipped {
                reason: "sample_cap",
                trimmed_parent,
            };
        }
    }
    if recipe.roles.len() != groups.len() {
        return Processed::Skipped {
            reason: "role_mismatch",
            trimmed_parent,
        };
    }
    let mut record = match dmhy_record(&training_filename, &recipe.template_id, &recipe.roles) {
        Some(record) => record,
        None => {
            return Processed::Skipped {
                reason: "role_mismatch",
                trimmed_parent,
            }
        }
    };
    if recipe.count.unwrap_or(0) <= args.audit_max_count && has_blocking_low_frequency_warning(&record)
    {
        return Processed::Skipped {
            reason: "low_frequency_audit_warning",
            trimmed_parent,
        };
    }
    if trimmed_parent {
        record.source_filename = Some(original.to_string());
        record.path_trimmed = Some(true);
        return Processed::Written {
            record,
            trimmed_parent: true,
        };
    }
    Processed::Written {
        record,
        trimmed_parent: false,
    }
}

fn has_blocking_low_frequency_warning(record: &Record) -> bool {
    audit_warnings(record).iter().any(|warning| {
        matches!(
            warning.as_str(),
            "hash_labeled" | "multiple_title_spans" | "no_title" | "path_retained"
        )
    })
}

fn tokenize(value: &str) -> Vec<String> {
    let mut output = Vec::new();
    let mut index = 0;
    while index < value.len() {
        let rest = &value[index..];
        if let Some((token, len)) = next_token(rest) {
            output.push(token);
            index += len;
        } else {
            let ch = rest.chars().next().unwrap();
            output.push(ch.to_string());
            index += ch.len_utf8();
        }
    }
    output
}

fn next_token(rest: &str) -> Option<(String, usize)> {
    let first = rest.chars().next()?;
    if first == '[' {
        if let Some(end) = rest.find(']') {
            if end <= 121 {
                return Some((rest[..=end].to_string(), end + 1));
            }
        }
    }
    if first == '(' {
        if let Some(end) = rest.find(')') {
            if end <= 121 {
                return Some((rest[..=end].to_string(), end + 1));
            }
        }
    }
    if first == '【' {
        if let Some(end) = rest.find('】') {
            if rest[..end].chars().count() <= 120 {
                return Some((
                    rest[..end + '】'.len_utf8()].to_string(),
                    end + '】'.len_utf8(),
                ));
            }
        }
    }
    for re in TOKEN_REGEXES.iter() {
        if let Some(mat) = re.find(rest) {
            if mat.start() == 0 && mat.end() > 0 {
                return Some((mat.as_str().to_string(), mat.end()));
            }
        }
    }
    None
}

fn strip_wrapper(token: &str) -> String {
    let chars: Vec<char> = token.chars().collect();
    if chars.len() >= 2 {
        let first = chars[0];
        let last = chars[chars.len() - 1];
        if (first == '[' && last == ']')
            || (first == '(' && last == ')')
            || (first == '【' && last == '】')
        {
            return chars[1..chars.len() - 1]
                .iter()
                .collect::<String>()
                .trim()
                .to_string();
        }
    }
    token.trim().to_string()
}

fn split_inner(inner: &str) -> Vec<String> {
    let mut parts = Vec::new();
    let mut current = String::new();
    for ch in inner.chars() {
        if ch.is_whitespace() || "_.,+/&|-()（）".contains(ch) {
            if !current.is_empty() {
                parts.push(std::mem::take(&mut current));
            }
        } else {
            current.push(ch);
        }
    }
    if !current.is_empty() {
        parts.push(current);
    }
    parts
}

fn compact_for_classify(text: &str) -> String {
    text.chars()
        .filter(|ch| !ch.is_whitespace() && !matches!(ch, '_' | '.' | ',' | '-'))
        .collect()
}

fn classify_atom(text: &str) -> String {
    let cleaned = strip_wrapper(text);
    let compact = compact_for_classify(&cleaned);
    if cleaned.is_empty() {
        return "EMPTY".to_string();
    }
    if HASH_RE.is_match(&cleaned) {
        return "HASH".to_string();
    }
    if RESOLUTION_RE.is_match(&cleaned) {
        return "RESOLUTION".to_string();
    }
    if DATE_RE.is_match(&cleaned) {
        return "DATE".to_string();
    }
    if EPISODE_VERSION_RE.is_match(&compact) {
        return "EPISODE_VERSION".to_string();
    }
    if SXE_RE.is_match(&compact) {
        return "SXE".to_string();
    }
    if EPISODE_RE.is_match(&compact) {
        return "EPISODE".to_string();
    }
    if EPISODE_CJK_RE.is_match(&cleaned) {
        return "EPISODE".to_string();
    }
    if EPISODE_BATCH_RE.is_match(&cleaned) {
        return "EPISODE_RANGE".to_string();
    }
    if EPISODE_RANGE_RE.is_match(&cleaned) {
        return "EPISODE_RANGE".to_string();
    }
    if EPISODE_RE.is_match(&cleaned) {
        return "EPISODE".to_string();
    }
    if SEASON_RE.is_match(&cleaned) {
        return "SEASON".to_string();
    }
    if SPECIAL_RE.is_match(&cleaned) {
        return "SPECIAL".to_string();
    }
    if VOLUME_RE.is_match(&cleaned) {
        return "VOLUME".to_string();
    }
    if LANG_RE.is_match(&cleaned) || lang_block_matches(&cleaned) {
        return "LANG".to_string();
    }
    if MEDIA_RE.is_match(&cleaned) {
        return "MEDIA".to_string();
    }
    "TEXT".to_string()
}

fn lang_block_matches(text: &str) -> bool {
    let upper = text.to_ascii_uppercase();
    if ["CHS", "CHT", "ZHS", "ZHT", "BIG5"]
        .iter()
        .any(|marker| upper.contains(marker))
    {
        return true;
    }
    if upper.contains("GB") {
        return true;
    }
    if [
        "简繁", "简日", "繁日", "简体", "繁体", "雙語", "双语", "内封", "外挂",
    ]
    .iter()
    .any(|marker| text.contains(marker))
    {
        return true;
    }
    let chars: Vec<char> = text.chars().collect();
    chars.windows(2).enumerate().any(|(index, pair)| {
        pair[0] == '字' && pair[1] == '幕' && !matches!(chars.get(index + 2), Some('组' | '組'))
    })
}

fn classify_token(token: &str) -> String {
    if token.is_empty() {
        return "EMPTY".to_string();
    }
    if token.chars().all(char::is_whitespace) {
        return "SPACE".to_string();
    }
    if token.chars().all(|ch| ch == '/' || ch == '\\') {
        return "PATH".to_string();
    }
    if token.chars().all(|ch| "-_.:：+&|".contains(ch)) {
        return "SEP".to_string();
    }
    if token.starts_with('[') || token.starts_with('(') || token.starts_with('【') {
        let inner = strip_wrapper(token);
        let parts = split_inner(&inner);
        let whole_class = classify_atom(&inner);
        let inner_class = if whole_class != "TEXT" {
            if whole_class == "LANG" && parts.len() > 1 {
                let part_classes: Vec<String> =
                    parts.iter().map(|part| classify_atom(part)).collect();
                if part_classes.iter().all(|item| item == &part_classes[0]) {
                    part_classes[0].clone()
                } else if part_classes.iter().all(|item| is_media_block_class(item)) {
                    "MEDIA_BLOCK".to_string()
                } else {
                    whole_class
                }
            } else {
                whole_class
            }
        } else if parts.is_empty() {
            "EMPTY".to_string()
        } else {
            let part_classes: Vec<String> = parts.iter().map(|part| classify_atom(part)).collect();
            if part_classes.iter().all(|item| item == &part_classes[0]) {
                part_classes[0].clone()
            } else if part_classes.iter().all(|item| is_media_block_class(item)) {
                "MEDIA_BLOCK".to_string()
            } else if part_classes.iter().any(|item| is_media_block_class(item))
                && parts.iter().zip(part_classes.iter()).all(|(part, item)| {
                    is_media_block_class(item)
                        || matches!(part.to_ascii_lowercase().as_str(), "anime" | "アニメ")
                })
            {
                "MEDIA_BLOCK".to_string()
            } else if part_classes.iter().any(|item| item == "TEXT") {
                "TEXT".to_string()
            } else {
                let mut set: Vec<String> = part_classes
                    .into_iter()
                    .collect::<HashSet<_>>()
                    .into_iter()
                    .collect();
                set.sort();
                set.join("_")
            }
        };
        return format!("BRACKET_{inner_class}");
    }
    classify_atom(token)
}

fn is_media_block_class(value: &str) -> bool {
    matches!(value, "MEDIA" | "RESOLUTION" | "LANG" | "HASH" | "DATE")
}

fn compact_token_groups(_tokens: &[String], classes: &[String]) -> Vec<Group> {
    let mut groups: Vec<Group> = Vec::new();
    let mut previous: Option<String> = None;
    for (index, token_class) in classes.iter().enumerate() {
        let current = if token_class == "SPACE" {
            "SEP"
        } else {
            token_class
        }
        .to_string();
        if previous.as_deref() == Some(current.as_str())
            && matches!(current.as_str(), "SEP" | "TEXT")
        {
            groups.last_mut().unwrap().indices.push(index);
        } else {
            groups.push(Group {
                indices: vec![index],
                class_name: current.clone(),
            });
        }
        previous = Some(current);
    }
    groups
}

fn template_key_for_filename(filename: &str) -> (String, Vec<String>, Vec<String>, Vec<Group>) {
    let tokens = tokenize(filename);
    let classes: Vec<String> = tokens.iter().map(|token| classify_token(token)).collect();
    let groups = compact_token_groups(&tokens, &classes);
    let key = groups
        .iter()
        .map(|group| group.class_name.as_str())
        .collect::<Vec<_>>()
        .join(" ");
    (key, tokens, classes, groups)
}

fn suggested_roles(template: &str) -> Vec<String> {
    let items: Vec<&str> = template.split_whitespace().collect();
    let mut roles = vec!["O".to_string(); items.len()];
    let mut segment_starts = vec![0usize];
    for (index, item) in items.iter().enumerate() {
        if *item == "PATH" {
            segment_starts.push(index + 1);
        }
    }
    for (index, item) in items.iter().enumerate() {
        roles[index] = if item.contains("EPISODE_VERSION") {
            "EPISODE_VERSION"
        } else if item.contains("EPISODE_RANGE") {
            "EPISODE_RANGE"
        } else if item.contains("EPISODE") || item.contains("SXE") {
            "EPISODE"
        } else if item.contains("RESOLUTION") {
            "RESOLUTION"
        } else if item.contains("HASH") {
            "HASH"
        } else if item.contains("LANG") || item.contains("MEDIA") {
            "SOURCE"
        } else if item.contains("SPECIAL") {
            "SPECIAL"
        } else if item.contains("SEASON") {
            "SEASON"
        } else if item.contains("VOLUME") {
            "VOLUME"
        } else {
            "O"
        }
        .to_string();
    }
    for (offset, start) in segment_starts.iter().enumerate() {
        let end = if offset + 1 < segment_starts.len() {
            segment_starts[offset + 1] - 1
        } else {
            items.len()
        };
        if *start >= end {
            continue;
        }
        let first_structural = (*start..end)
            .find(|&index| {
                items[index].contains("EPISODE")
                    || matches!(items[index], "SXE" | "SPECIAL" | "SEASON")
            })
            .unwrap_or(end);
        let bracket_text: Vec<usize> = (*start..first_structural)
            .filter(|&index| items[index] == "BRACKET_TEXT" && roles[index] == "O")
            .collect();
        let text: Vec<usize> = (*start..first_structural)
            .filter(|&index| items[index] == "TEXT" && roles[index] == "O")
            .collect();
        if bracket_text.len() >= 2 {
            roles[bracket_text[0]] = "GROUP".to_string();
            for index in bracket_text.iter().skip(1) {
                roles[*index] = "TITLE".to_string();
            }
        } else if bracket_text.len() == 1 {
            roles[bracket_text[0]] = if text.is_empty() {
                "TITLE"
            } else if bracket_text[0] == *start {
                "GROUP"
            } else {
                "TITLE"
            }
            .to_string();
        }
        for index in text {
            roles[index] = "TITLE".to_string();
        }
        if !roles[*start..end].iter().any(|role| role == "TITLE")
            && !items[*start..end].is_empty()
            && items[*start].contains("EPISODE")
        {
            let mut run = Vec::new();
            for index in (*start + 1)..end {
                if items[index] == "TEXT" && roles[index] == "O" {
                    run.push(index);
                    continue;
                }
                if items[index] == "SEP" {
                    continue;
                }
                if !run.is_empty() {
                    break;
                }
            }
            if run.len() >= 2 {
                for index in run {
                    roles[index] = "TITLE".to_string();
                }
            }
        }
    }
    roles
}

fn filename_has_title(filename: &str) -> bool {
    let (key, _, _, _) = template_key_for_filename(filename);
    suggested_roles(&key).iter().any(|role| role == "TITLE")
}

fn training_filename_for(original: &str) -> (String, bool) {
    let parts: Vec<&str> = original
        .split(|ch| ch == '/' || ch == '\\')
        .map(str::trim)
        .filter(|part| !part.is_empty())
        .collect();
    if parts.len() >= 2 && filename_has_title(parts[parts.len() - 1]) {
        if parts.len() >= 3 && path_segment_has_season(parts[parts.len() - 2]) {
            if !path_segment_is_plain_season(parts[parts.len() - 2]) {
                return (parts[parts.len() - 1].to_string(), true);
            }
            let parent_seasons = path_segment_seasons(parts[parts.len() - 2]);
            let leaf_seasons = path_segment_seasons(parts[parts.len() - 1]);
            if parent_seasons
                .iter()
                .any(|season| leaf_seasons.contains(season))
            {
                (parts[parts.len() - 1].to_string(), true)
            } else {
                (parts[parts.len() - 2..].join("/"), true)
            }
        } else {
            (parts[parts.len() - 1].to_string(), true)
        }
    } else {
        (original.to_string(), false)
    }
}

fn path_segment_is_plain_season(segment: &str) -> bool {
    let cleaned = strip_wrapper(segment).trim().to_string();
    PLAIN_SEASON_SEGMENT_RE.is_match(&cleaned)
}

fn path_segment_has_season(value: &str) -> bool {
    PATH_SEGMENT_SEASON_RE.is_match(value)
}

fn path_segment_seasons(value: &str) -> HashSet<u8> {
    SEASON_WORD_NUMBER_RE
        .captures_iter(value)
        .chain(S_NUMBER_SEGMENT_RE.captures_iter(value))
        .chain(SXE_SEASON_RE.captures_iter(value))
        .filter_map(|captures| captures.get(1))
        .filter_map(|item| item.as_str().parse::<u8>().ok())
        .collect()
}

fn has_encoding_noise(value: &str) -> bool {
    if value.contains('\u{fffd}') {
        return true;
    }
    let markers = [
        "譁", "蜈", "螟", "蟄", "謇", "邱", "荳", "縺", "繧", "莨", "鬆", "髯",
    ];
    let marker_hits = markers
        .iter()
        .map(|marker| value.matches(marker).count())
        .sum::<usize>();
    let halfwidth_hits = value
        .chars()
        .filter(|ch| ('\u{ff61}'..='\u{ff9f}').contains(ch))
        .count();
    marker_hits >= 2 || (marker_hits >= 1 && halfwidth_hits >= 1)
}

fn has_non_anime_noise(value: &str) -> bool {
    let normalized = value.replace('\\', "/").trim().to_ascii_lowercase();
    normalized == "mtv" || normalized.starts_with("mtv/") || normalized.contains("/mtv/")
}

fn normalized_path_segment(value: &str) -> String {
    value
        .split_whitespace()
        .collect::<String>()
        .to_ascii_lowercase()
}

fn path_segment_is_episodeish(value: &str) -> bool {
    let (_, _, _, groups) = template_key_for_filename(value);
    let structural: Vec<&String> = groups
        .iter()
        .map(|group| &group.class_name)
        .filter(|item| item.as_str() != "SEP")
        .collect();
    !structural.is_empty()
        && structural
            .iter()
            .all(|item| item.starts_with("EPISODE") || item.as_str() == "SPECIAL")
}

fn has_abstract_path_noise(value: &str) -> bool {
    let parts: Vec<&str> = value
        .split(|ch| ch == '/' || ch == '\\')
        .map(str::trim)
        .filter(|part| !part.is_empty())
        .collect();
    if parts.len() < 3 {
        return false;
    }
    if normalized_path_segment(parts[0]) == normalized_path_segment(parts[parts.len() - 1]) {
        return true;
    }
    path_segment_is_episodeish(parts[0]) && path_segment_is_episodeish(parts[parts.len() - 1])
}

fn role_label(role: &str) -> String {
    let entity = match role {
        "GROUP" => Some("GROUP"),
        "TITLE" => Some("TITLE"),
        "EPISODE" | "EPISODE_VERSION" | "EPISODE_RANGE" => Some("EPISODE"),
        "SEASON" => Some("SEASON"),
        "SPECIAL" | "VOLUME" => Some("SPECIAL"),
        "RESOLUTION" => Some("RESOLUTION"),
        "SOURCE" => Some("SOURCE"),
        _ => None,
    };
    entity.map_or_else(|| "O".to_string(), |entity| format!("B-{entity}"))
}

fn is_separator(piece: &str) -> bool {
    piece.is_empty()
        || piece
            .chars()
            .all(|ch| ch.is_whitespace() || !ch.is_alphanumeric())
}

fn char_kind(ch: char) -> &'static str {
    if ch.is_whitespace() || !ch.is_alphanumeric() {
        "sep"
    } else if ch.is_ascii_digit() {
        "digit"
    } else if ch.is_ascii_alphabetic() {
        "alpha"
    } else {
        "text"
    }
}

fn split_refined_token(token: &str) -> Vec<String> {
    let whole_class = classify_atom(token);
    let is_wrapped = {
        let chars: Vec<char> = token.chars().collect();
        chars.len() >= 2
            && ((chars[0] == '[' && chars[chars.len() - 1] == ']')
                || (chars[0] == '(' && chars[chars.len() - 1] == ')')
                || (chars[0] == '【' && chars[chars.len() - 1] == '】'))
    };
    if !is_wrapped
        && matches!(
            whole_class.as_str(),
            "RESOLUTION" | "MEDIA" | "LANG" | "HASH" | "SXE" | "EPISODE_VERSION"
        )
        && token.chars().all(char::is_alphanumeric)
    {
        return vec![token.to_string()];
    }
    if !is_wrapped && whole_class == "EPISODE" && SIMPLE_EPISODE_RE.is_match(token) {
        return vec![token.to_string()];
    }
    let mut pieces = Vec::new();
    let mut current = String::new();
    let mut current_kind: Option<&str> = None;
    for ch in token.chars() {
        let kind = char_kind(ch);
        if kind == "sep" {
            if !current.is_empty() {
                pieces.push(std::mem::take(&mut current));
                current_kind = None;
            }
            pieces.push(ch.to_string());
            continue;
        }
        if !current.is_empty() && current_kind != Some(kind) {
            pieces.push(std::mem::take(&mut current));
        }
        current.push(ch);
        current_kind = Some(kind);
    }
    if !current.is_empty() {
        pieces.push(current);
    }
    let mut merged = Vec::new();
    let mut index = 0;
    while index < pieces.len() {
        if index + 2 < pieces.len()
            && !is_separator(&pieces[index])
            && is_separator(&pieces[index + 1])
            && !is_separator(&pieces[index + 2])
        {
            let combined = format!(
                "{}{}{}",
                pieces[index],
                pieces[index + 1],
                pieces[index + 2]
            );
            let combined_class = classify_atom(&combined);
            if !pieces[index + 1].chars().any(char::is_whitespace)
                && matches!(pieces[index + 1].as_str(), "." | "x" | "X" | "×")
                && matches!(
                    combined_class.as_str(),
                    "RESOLUTION" | "MEDIA" | "LANG" | "HASH" | "SXE" | "EPISODE_VERSION"
                )
            {
                merged.push(combined);
                index += 3;
                continue;
            }
        }
        if !is_separator(&pieces[index]) {
            let mut end = index;
            let mut combined = String::new();
            while end < pieces.len() && !is_separator(&pieces[end]) {
                combined.push_str(&pieces[end]);
                end += 1;
            }
            if end > index + 1 && is_mergeable_refined_class(&classify_atom(&combined)) {
                merged.push(combined);
                index = end;
                continue;
            }
        }
        if index + 1 < pieces.len()
            && !is_separator(&pieces[index])
            && !is_separator(&pieces[index + 1])
        {
            let combined = format!("{}{}", pieces[index], pieces[index + 1]);
            if is_mergeable_refined_class(&classify_atom(&combined)) {
                merged.push(combined);
                index += 2;
                continue;
            }
        }
        merged.push(pieces[index].clone());
        index += 1;
    }
    merged
}

fn is_mergeable_refined_class(value: &str) -> bool {
    matches!(
        value,
        "RESOLUTION" | "MEDIA" | "LANG" | "HASH" | "SXE" | "EPISODE_VERSION" | "SEASON"
    )
}

fn label_for_refined_piece(piece: &str, role: &str, token_class: &str) -> String {
    if is_separator(piece) {
        return "O".to_string();
    }
    let atom_class = classify_atom(piece);
    let upper = piece.to_ascii_uppercase();
    if matches!(role, "EPISODE" | "EPISODE_VERSION" | "EPISODE_RANGE") {
        if atom_class == "SEASON" {
            return "B-SEASON".to_string();
        }
        if matches!(atom_class.as_str(), "EPISODE" | "EPISODE_VERSION" | "SXE")
            || piece.chars().all(|ch| ch.is_ascii_digit())
        {
            return "B-EPISODE".to_string();
        }
        if matches!(atom_class.as_str(), "SPECIAL" | "VOLUME")
            || matches!(
                upper.as_str(),
                "OVA" | "OAD" | "SP" | "PV" | "CM" | "OP" | "ED" | "NCOP" | "NCED"
            )
        {
            return "B-SPECIAL".to_string();
        }
        return "O".to_string();
    }
    if role == "SOURCE" || matches!(token_class, "BRACKET_MEDIA_BLOCK" | "MEDIA_BLOCK") {
        if atom_class == "RESOLUTION" {
            return "B-RESOLUTION".to_string();
        }
        if atom_class == "HASH" {
            return "O".to_string();
        }
        if matches!(atom_class.as_str(), "MEDIA" | "LANG") {
            return "B-SOURCE".to_string();
        }
        if matches!(atom_class.as_str(), "SPECIAL" | "VOLUME") {
            return "B-SPECIAL".to_string();
        }
        return if matches!(
            upper.as_str(),
            "END" | "FIN" | "COMPLETE" | "TV" | "全集" | "全"
        ) {
            "O".to_string()
        } else {
            "B-SOURCE".to_string()
        };
    }
    if role == "RESOLUTION" {
        return if atom_class == "RESOLUTION" || piece.chars().all(|ch| ch.is_ascii_digit()) {
            "B-RESOLUTION".to_string()
        } else {
            "O".to_string()
        };
    }
    role_label(role)
}

fn split_sxe_token(token: &str) -> Option<(Vec<String>, Vec<String>)> {
    let caps = SXE_VALUE_RE.captures(token)?;
    let mut pieces = vec![
        "S".to_string(),
        caps[1].to_string(),
        "E".to_string(),
        caps[2].to_string(),
    ];
    let mut labels = vec![
        "O".to_string(),
        "B-SEASON".to_string(),
        "O".to_string(),
        "B-EPISODE".to_string(),
    ];
    if let Some(version) = caps.get(3) {
        pieces.push("v".to_string());
        pieces.push(version.as_str().to_string());
        labels.push("O".to_string());
        labels.push("O".to_string());
    }
    Some((pieces, labels))
}

fn split_episode_token(token: &str) -> Option<(Vec<String>, Vec<String>)> {
    let caps = EPISODE_VALUE_RE.captures(token)?;
    let mut pieces = vec![caps[1].to_string(), caps[2].to_string()];
    let mut labels = vec!["O".to_string(), "B-EPISODE".to_string()];
    if let Some(version) = caps.get(3) {
        pieces.push("v".to_string());
        pieces.push(version.as_str().to_string());
        labels.push("O".to_string());
        labels.push("O".to_string());
    }
    Some((pieces, labels))
}

fn split_season_token(token: &str) -> Option<(Vec<String>, Vec<String>)> {
    let caps = SEASON_VALUE_RE.captures(token)?;
    Some((
        vec!["S".to_string(), caps[1].to_string()],
        vec!["O".to_string(), "B-SEASON".to_string()],
    ))
}

fn group_text(tokens: &[String], group: &Group) -> String {
    strip_wrapper(
        &group
            .indices
            .iter()
            .map(|&index| tokens[index].as_str())
            .collect::<String>(),
    )
}

fn is_special_title_phrase(text: &str) -> bool {
    let normalized = SPECIAL_SPACE_RE
        .replace_all(text, " ")
        .trim()
        .to_ascii_uppercase();
    matches!(
        normalized.as_str(),
        "CM" | "EVENT"
            | "EIZOU"
            | "LOGO"
            | "MENU"
            | "OMAKE"
            | "PREVIEW"
            | "PV"
            | "THEATER GREETING EVENT"
            | "TOKUTEN"
            | "TRAILER"
            | "WORLD PREMIERE"
    ) || SPECIAL_TITLE_PHRASE_RE.is_match(text)
}

fn adjust_contextual_roles(tokens: &[String], groups: &[Group], roles: &[String]) -> Vec<String> {
    let mut output = roles.to_vec();
    let ep_markers = ["EP", "E", "Episode", "ep", "episode"];
    let roman = ["I", "II", "III", "IV", "V", "VI", "VII", "VIII", "IX"];
    if !output.iter().any(|role| role == "TITLE")
        && roles
            .first()
            .is_some_and(|role| role.starts_with("EPISODE"))
    {
        let mut title_run = Vec::new();
        for index in 1..roles.len() {
            if groups[index].class_name == "TEXT" && output[index] == "O" {
                title_run.push(index);
                continue;
            }
            if groups[index].class_name == "SEP" {
                continue;
            }
            if !title_run.is_empty() {
                break;
            }
        }
        if title_run.len() >= 2 {
            let last_title_index = *title_run.last().unwrap();
            let later_structural = roles[last_title_index + 1..].iter().any(|role| {
                role.starts_with("EPISODE") || matches!(role.as_str(), "SEASON" | "SPECIAL")
            });
            if group_text(tokens, &groups[0])
                .chars()
                .all(|ch| ch.is_ascii_digit())
                && later_structural
            {
                output[0] = "TITLE".to_string();
            }
            for index in title_run {
                output[index] = "TITLE".to_string();
            }
        }
    }
    if roles
        .first()
        .is_some_and(|role| role.starts_with("EPISODE"))
        && group_text(tokens, &groups[0])
            .chars()
            .all(|ch| ch.is_ascii_digit())
    {
        if let Some(first_title) = output.iter().position(|role| role == "TITLE") {
            let later_structural = roles[first_title + 1..].iter().any(|role| {
                role.starts_with("EPISODE") || matches!(role.as_str(), "SEASON" | "SPECIAL")
            });
            if later_structural {
                output[0] = "TITLE".to_string();
            }
        }
    }
    for index in 0..roles.len() {
        let text = group_text(tokens, &groups[index]);
        if output[index] == "O" && groups[index].class_name.contains("SXE") {
            output[index] = "EPISODE".to_string();
        }
        if roles[index].starts_with("EPISODE") && YEAR_RANGE_RE.is_match(&text) {
            output[index] = "O".to_string();
            continue;
        }
        if roles[index].starts_with("EPISODE") && (2..roles.len()).contains(&index) {
            let previous_text = group_text(tokens, &groups[index - 2]);
            let next_special = output[index + 1..roles.len().min(index + 4)]
                .iter()
                .any(|role| role == "SPECIAL");
            let next_episode = roles[index + 1..]
                .iter()
                .any(|role| role.starts_with("EPISODE"));
            if groups[index - 1].class_name == "SEP"
                && matches!(
                    previous_text.to_ascii_lowercase().as_str(),
                    "vol" | "volume"
                )
            {
                let next_text_before_episode = (index + 1..roles.len())
                    .find(|&cursor| groups[cursor].class_name != "SEP")
                    .is_some_and(|cursor| {
                        groups[cursor].class_name == "TEXT"
                            && roles[cursor + 1..]
                                .iter()
                                .any(|role| role.starts_with("EPISODE"))
                    });
                if next_text_before_episode {
                    output[index - 2] = "TITLE".to_string();
                    output[index] = "TITLE".to_string();
                    continue;
                }
                output[index - 2] = "SPECIAL".to_string();
                output[index] = "SPECIAL".to_string();
                continue;
            }
            if output[index - 2] == "TITLE"
                && groups[index - 1].class_name == "SEP"
                && previous_text.len() <= 4
                && previous_text.is_ascii()
                && previous_text.chars().all(|ch| ch.is_ascii_alphabetic())
                && text.chars().all(|ch| ch.is_ascii_digit())
                && text.len() <= 3
                && (next_special || next_episode)
            {
                output[index] = "TITLE".to_string();
                continue;
            }
        }
        if roles[index].starts_with("EPISODE")
            && index >= 2
            && output[..index].iter().any(|role| role == "TITLE")
            && group_text(tokens, &groups[index])
                .chars()
                .all(|ch| ch.is_ascii_digit())
        {
            let next_episode_word = index + 2 < roles.len()
                && groups[index + 1].class_name == "SEP"
                && group_text(tokens, &groups[index + 2]).eq_ignore_ascii_case("episode");
            if next_episode_word {
                let mut run = Vec::new();
                let mut cursor = index + 2;
                while cursor < roles.len() {
                    if groups[cursor].class_name == "SEP" {
                        cursor += 1;
                        continue;
                    }
                    if groups[cursor].class_name == "TEXT" && !roles[cursor].starts_with("EPISODE")
                    {
                        run.push(cursor);
                        cursor += 1;
                        continue;
                    }
                    break;
                }
                let later_episode = roles[cursor..]
                    .iter()
                    .any(|role| role.starts_with("EPISODE"));
                if run.len() >= 2 && later_episode {
                    output[index] = "TITLE".to_string();
                    for item in run {
                        output[item] = "TITLE".to_string();
                    }
                    continue;
                }
            }
        }
        if roles[index] == "TITLE" && is_special_title_phrase(&text) {
            output[index] = "SPECIAL".to_string();
            continue;
        }
        if roles[index] == "TITLE" && matches!(text.as_str(), "第" | "話" | "话" | "回" | "集")
        {
            output[index] = "O".to_string();
            continue;
        }
        if output[index] == "O"
            && groups[index].class_name == "TEXT"
            && roles[index + 1..].iter().any(|role| role.starts_with("EPISODE"))
            && text.chars().any(|ch| ch.is_alphabetic())
            && !ep_markers.contains(&text.as_str())
        {
            if let Some(last_title) = output[..index].iter().rposition(|role| role == "TITLE") {
                let episode_since_title = output[last_title + 1..index]
                    .iter()
                    .any(|role| role.starts_with("EPISODE"));
                if !episode_since_title {
                    output[index] = "TITLE".to_string();
                    continue;
                }
            }
        }
        if roles[index] == "TITLE"
            && matches!(text.to_ascii_lowercase().as_str(), "season" | "saison")
            && index + 2 < roles.len()
            && groups[index + 1].class_name == "SEP"
            && roles[index + 2].starts_with("EPISODE")
        {
            output[index] = "O".to_string();
            output[index + 2] = "SEASON".to_string();
            continue;
        }
        if roles[index] == "TITLE"
            && text == text.to_ascii_uppercase()
            && roman.contains(&text.as_str())
        {
            let previous_title = output[..index].iter().any(|role| role == "TITLE");
            let next_structural = roles[index + 1..]
                .iter()
                .any(|role| role.starts_with("EPISODE") || role == "SPECIAL");
            if previous_title && next_structural {
                output[index] = "SEASON".to_string();
                continue;
            }
        }
        if roles[index].starts_with("EPISODE") && index + 4 < roles.len() {
            if groups[index + 1].class_name == "SEP"
                && ep_markers.contains(&group_text(tokens, &groups[index + 2]).as_str())
                && groups[index + 3].class_name == "SEP"
                && roles[index + 4].starts_with("EPISODE")
            {
                output[index] = "TITLE".to_string();
                output[index + 2] = "O".to_string();
            }
        }
        if roles[index].starts_with("EPISODE") {
            let previous_text = if index >= 1 {
                group_text(tokens, &groups[index - 1])
            } else {
                String::new()
            };
            let next_text = if index + 1 < roles.len() {
                group_text(tokens, &groups[index + 1])
            } else {
                String::new()
            };
            if previous_text.contains('点')
                || previous_text.contains('點')
                || previous_text.contains("晚上")
                || previous_text.contains("上午")
                || previous_text.contains("下午")
                || next_text.contains('点')
                || next_text.contains('點')
                || next_text.contains('半')
            {
                output[index] = "O".to_string();
            }
        }
    }
    output
}

fn title_candidates(groups: &[Group], roles: &[String]) -> Vec<(usize, usize)> {
    let mut candidates = Vec::new();
    let mut index = 0;
    while index < roles.len() {
        if roles[index] != "TITLE" {
            index += 1;
            continue;
        }
        let start = index;
        index += 1;
        loop {
            if index < roles.len()
                && roles[index] == "TITLE"
                && !(groups[index - 1].class_name == "BRACKET_TEXT"
                    && groups[index].class_name == "BRACKET_TEXT")
            {
                index += 1;
                continue;
            }
            if index + 1 < roles.len()
                && roles[index] == "O"
                && groups[index].class_name == "SEP"
                && roles[index + 1] == "TITLE"
            {
                index += 2;
                continue;
            }
            break;
        }
        candidates.push((start, index));
    }
    candidates
}

fn enforce_single_title_candidate(
    groups: &[Group],
    roles: &[String],
) -> (Vec<String>, Vec<String>) {
    let candidates = title_candidates(groups, roles);
    if candidates.len() <= 1 {
        return (roles.to_vec(), Vec::new());
    }
    let first_anchor = roles
        .iter()
        .position(|role| {
            role.starts_with("EPISODE")
                || matches!(
                    role.as_str(),
                    "SEASON" | "SPECIAL" | "SOURCE" | "RESOLUTION"
                )
        })
        .unwrap_or(roles.len());
    let before_anchor: Vec<(usize, usize)> = candidates
        .iter()
        .copied()
        .filter(|(_, end)| *end <= first_anchor)
        .collect();
    let selected = (if before_anchor.is_empty() {
        &candidates
    } else {
        &before_anchor
    })
    .iter()
    .max_by_key(|(start, end)| (*end, end - start))
    .copied()
    .unwrap();
    let mut output = roles.to_vec();
    let mut dropped = Vec::new();
    for (start, end) in candidates {
        if (start, end) == selected {
            continue;
        }
        for index in start..end {
            if output[index] == "TITLE" {
                output[index] = "O".to_string();
                dropped.push(index.to_string());
            }
        }
    }
    (output, dropped)
}

fn normalize_generated_tokens(tokens: &[String], labels: &[String]) -> (Vec<String>, Vec<String>) {
    let mut output_tokens = Vec::new();
    let mut output_labels = Vec::new();
    for (token, label) in tokens.iter().zip(labels.iter()) {
        for piece in split_generated_token(token) {
            output_labels.push(if label == "O" || is_standalone_separator(&piece) {
                "O".to_string()
            } else {
                label.clone()
            });
            output_tokens.push(piece);
        }
    }
    (output_tokens, output_labels)
}

fn normalize_title_token(token: &str) -> (Vec<String>, Vec<String>) {
    let pieces = split_generated_token(token);
    let labels = pieces
        .iter()
        .map(|piece| {
            if is_standalone_separator(piece) {
                "O".to_string()
            } else if CJK_SEASON_TOKEN_RE.is_match(piece) {
                "B-SEASON".to_string()
            } else {
                "B-TITLE".to_string()
            }
        })
        .collect();
    (pieces, labels)
}

fn split_generated_token(token: &str) -> Vec<String> {
    let mut pieces = Vec::new();
    let mut current = String::new();
    for ch in token.chars() {
        if ch.is_whitespace() || !ch.is_alphanumeric() {
            if !current.is_empty() {
                pieces.push(std::mem::take(&mut current));
            }
            pieces.push(ch.to_string());
        } else {
            current.push(ch);
        }
    }
    if !current.is_empty() {
        pieces.push(current);
    }
    pieces
}

fn is_standalone_separator(token: &str) -> bool {
    token.chars().count() == 1
        && token
            .chars()
            .next()
            .is_some_and(|ch| ch.is_whitespace() || !ch.is_alphanumeric())
}

fn project_refined_tokens(
    tokens: &[String],
    groups: &[Group],
    roles: &[String],
) -> (Vec<String>, Vec<String>) {
    let mut output_tokens = Vec::new();
    let mut output_labels = Vec::new();
    for (group_index, group) in groups.iter().enumerate() {
        let mut role = roles.get(group_index).map(String::as_str).unwrap_or("O");
        if matches!(group.class_name.as_str(), "SEP" | "PATH" | "EMPTY") {
            role = "O";
        }
        for &index in &group.indices {
            let token = &tokens[index];
            if matches!(
                role,
                "EPISODE"
                    | "EPISODE_VERSION"
                    | "EPISODE_RANGE"
                    | "SOURCE"
                    | "RESOLUTION"
                    | "SEASON"
            ) {
                if role == "SEASON" {
                    if let Some((pieces, labels)) = split_season_token(token) {
                        output_tokens.extend(pieces);
                        output_labels.extend(labels);
                        continue;
                    }
                }
                if matches!(role, "EPISODE" | "EPISODE_VERSION" | "EPISODE_RANGE") {
                    if let Some((pieces, labels)) = split_sxe_token(&strip_wrapper(token)) {
                        output_tokens.extend(pieces);
                        output_labels.extend(labels);
                        continue;
                    }
                    if let Some((pieces, labels)) = split_episode_token(&strip_wrapper(token)) {
                        output_tokens.extend(pieces);
                        output_labels.extend(labels);
                        continue;
                    }
                }
                for piece in split_refined_token(token) {
                    if matches!(role, "EPISODE" | "EPISODE_VERSION" | "EPISODE_RANGE") {
                        if let Some((pieces, labels)) = split_season_token(&piece) {
                            output_tokens.extend(pieces);
                            output_labels.extend(labels);
                            continue;
                        }
                        if let Some((pieces, labels)) = split_episode_token(&piece) {
                            output_tokens.extend(pieces);
                            output_labels.extend(labels);
                            continue;
                        }
                    }
                    let label = label_for_refined_piece(&piece, role, &group.class_name);
                    let (pieces, labels) = normalize_generated_tokens(&[piece], &[label]);
                    output_tokens.extend(pieces);
                    output_labels.extend(labels);
                }
            } else {
                if role == "TITLE" && matches!(token.as_str(), "第" | "話" | "话" | "回" | "集")
                {
                    output_tokens.push(token.clone());
                    output_labels.push("O".to_string());
                    continue;
                }
                if role == "TITLE" && token.ends_with('第') && token.chars().count() > 1 {
                    let trimmed = token.trim_end_matches('第').to_string();
                    let (pieces, labels) = normalize_generated_tokens(
                        &[trimmed, "第".to_string()],
                        &["B-TITLE".to_string(), "O".to_string()],
                    );
                    output_tokens.extend(pieces);
                    output_labels.extend(labels);
                    continue;
                }
                if role == "TITLE" {
                    let (pieces, labels) = normalize_title_token(token);
                    output_tokens.extend(pieces);
                    output_labels.extend(labels);
                    continue;
                }
                let (pieces, labels) =
                    normalize_generated_tokens(&[token.clone()], &[role_label(role)]);
                output_tokens.extend(pieces);
                output_labels.extend(labels);
            }
        }
    }
    (output_tokens, output_labels)
}

fn smooth_title_spans(tokens: &[String], labels: &[String]) -> Vec<String> {
    let joiners = [
        " ", ".", "-", "_", "·", "・", "×", "／", "/", "'", "’", ":", "：", "!", "！", "?",
        "？", ";", "；", ",", "，", "～", "~", "－", "(", ")", "（", "）", "[", "]", "【",
        "】", "｢", "｣", "「", "」", "☆", "@",
    ];
    let title_terminal_punctuation = ["!", "！", "?", "？"];
    let entity_joiners = [
        " ", ".", "-", "_", "·", "・", "×", "／", "/", "'", "’", ":", "：", "!", "！", "?",
        "？", ";", "；", ",", "，", "～", "~", "－", "(", ")", "（", "）", "[", "]", "【",
        "】", "｢", "｣", "「", "」", "☆", "@", "&", "＆",
    ];
    let mut output = labels.to_vec();
    for (index, (token, label)) in tokens.iter().zip(labels.iter()).enumerate() {
        if label != "O" || !entity_joiners.contains(&token.as_str()) {
            continue;
        }
        let mut left = index as isize - 1;
        while left >= 0
            && joiners.contains(&tokens[left as usize].as_str())
            && labels[left as usize] == "O"
        {
            left -= 1;
        }
        let mut right = index + 1;
        while right < tokens.len()
            && joiners.contains(&tokens[right].as_str())
            && labels[right] == "O"
        {
            right += 1;
        }
        if left >= 0 && right < tokens.len() {
            let left_label = &output[left as usize];
            let right_label = &labels[right];
            if left_label == right_label && matches!(left_label.as_str(), "B-TITLE" | "B-GROUP") {
                output[index] = left_label.clone();
            }
        }
        if title_terminal_punctuation.contains(&token.as_str()) && index > 0 {
            let left_label = &output[index - 1];
            if left_label == "B-TITLE" {
                output[index] = "B-TITLE".to_string();
            }
        }
    }
    output
}

fn dmhy_record(filename: &str, template_id: &str, roles: &[String]) -> Option<Record> {
    let (key, tokens, _classes, groups) = template_key_for_filename(filename);
    if groups.len() != roles.len() {
        return None;
    }
    let roles = adjust_contextual_roles(&tokens, &groups, roles);
    let (roles, dropped) = enforce_single_title_candidate(&groups, &roles);
    let (tokens, labels) = project_refined_tokens(&tokens, &groups, &roles);
    let labels = smooth_title_spans(&tokens, &labels);
    if tokens.len() != labels.len() {
        return None;
    }
    Some(Record {
        filename: filename.to_string(),
        tokens,
        labels,
        template_id: template_id.to_string(),
        template: key,
        source_filename: None,
        path_trimmed: None,
        dropped_title_candidate_positions: if dropped.is_empty() {
            None
        } else {
            Some(dropped)
        },
    })
}

#[cfg(test)]
mod tests {
    use super::*;

    fn labels_for(filename: &str) -> Vec<(String, String)> {
        let (key, _, _, _) = template_key_for_filename(filename);
        let roles = suggested_roles(&key);
        let record = dmhy_record(filename, "tpl_test", &roles).unwrap();
        record.tokens.into_iter().zip(record.labels).collect()
    }

    #[test]
    fn required_regressions() {
        let title_91 = labels_for("Title 91 EP 01 [1080p]");
        assert!(title_91.contains(&("91".to_string(), "B-TITLE".to_string())));
        assert!(title_91.contains(&("EP".to_string(), "O".to_string())));
        assert!(title_91.contains(&("01".to_string(), "B-EPISODE".to_string())));

        let event = labels_for("[HYSUB]Dragon Ball Super Broly[Theater Greeting Event][1080P]");
        assert!(event.contains(&("Theater".to_string(), "B-SPECIAL".to_string())));
        assert!(!event.contains(&("Theater".to_string(), "B-TITLE".to_string())));

        let roman = labels_for("Chibi Maruko-chan I 001");
        assert!(roman.contains(&("I".to_string(), "B-SEASON".to_string())));
        assert!(roman.contains(&("001".to_string(), "B-EPISODE".to_string())));

        let dxd = labels_for("High School D×D");
        assert!(dxd.contains(&("×".to_string(), "B-TITLE".to_string())));
        let colon_title = labels_for("Megumi no Daigo：Kyuukoku no Orange 06");
        assert!(colon_title.contains(&("：".to_string(), "B-TITLE".to_string())));

        let sxe = labels_for("S01E02");
        assert_eq!(
            sxe,
            vec![
                ("S".to_string(), "O".to_string()),
                ("01".to_string(), "B-SEASON".to_string()),
                ("E".to_string(), "O".to_string()),
                ("02".to_string(), "B-EPISODE".to_string())
            ]
        );
        let ep_prefix = labels_for("Toradora! EP01 [BD 1080p]");
        assert!(ep_prefix.contains(&("EP".to_string(), "O".to_string())));
        assert!(ep_prefix.contains(&("01".to_string(), "B-EPISODE".to_string())));
        let bracket_sxe = labels_for("[FLsnow.feat.PO][Himitsu_no_Aipri][1080P][S2E01]");
        assert!(bracket_sxe.contains(&("2".to_string(), "B-SEASON".to_string())));
        assert!(bracket_sxe.contains(&("01".to_string(), "B-EPISODE".to_string())));

        let cursed = labels_for("[Coalgirls]_C3-Cube_x_Cursed_x_Curious_01_[8E416230]");
        assert!(cursed.contains(&("x".to_string(), "B-TITLE".to_string())));
        assert!(!cursed.contains(&("x".to_string(), "B-SEASON".to_string())));
        let beyblade = labels_for("[jibaketa]Beyblade X - 118 (WEB 1920x1080 AVC AAC)");
        assert!(beyblade.contains(&("X".to_string(), "B-TITLE".to_string())));
        assert!(!beyblade.contains(&("X".to_string(), "B-SEASON".to_string())));
        let bang_title = labels_for("[Dymy][Gugure! Kokkuri-san][06][BIG5][1280X720]");
        assert!(bang_title.contains(&("!".to_string(), "B-TITLE".to_string())));
        let pso2 = labels_for("[Lilith-Raws] Phantasy Star Online 2 Episode Oracle - 01 [1080p]");
        assert!(pso2.contains(&("2".to_string(), "B-TITLE".to_string())));
        assert!(pso2.contains(&("Episode".to_string(), "B-TITLE".to_string())));
        assert!(pso2.contains(&("Oracle".to_string(), "B-TITLE".to_string())));
        assert!(pso2.contains(&("01".to_string(), "B-EPISODE".to_string())));
        let aikatsu = labels_for("Aikatsu Friends! - S2E01 (BD 1920x1080 x264 FLAC)");
        assert!(aikatsu.contains(&("!".to_string(), "B-TITLE".to_string())));
        let intro = labels_for("[VCB-Studio] LoveLive! µ's Live Collection [01][intro][1080p]");
        assert!(intro.contains(&("intro".to_string(), "B-SPECIAL".to_string())));
        let hash = labels_for("[Group][Title][01][1080p][00270AC8]");
        assert!(hash.contains(&("00270AC8".to_string(), "O".to_string())));
        let yamato = labels_for("[1995.01] YAMATO2520 Vol.1 明日への希望-0001");
        assert!(yamato.contains(&("YAMATO2520".to_string(), "B-TITLE".to_string())));
        assert!(yamato.contains(&("明日への希望".to_string(), "B-TITLE".to_string())));
        let ubw = labels_for("Fate／stay night [Unlimited Blade Works] #00 「プロローグ」");
        assert!(ubw.contains(&("Unlimited".to_string(), "B-TITLE".to_string())));
        assert!(!ubw.contains(&("Unlimited".to_string(), "B-GROUP".to_string())));
        let alias_title = labels_for("[Koten_Gars] Tegami Bachi; Letter Bee - 01 [1080p]");
        assert!(alias_title.contains(&(";".to_string(), "B-TITLE".to_string())));
        let comma_title =
            labels_for("[Studio GreenTea] Kamiina Botan, Yoeru Sugata wa Yuri no Hana [01]");
        assert!(comma_title.contains(&(",".to_string(), "B-TITLE".to_string())));
        let happy_lesson = labels_for("【DVD】 HAPPY☆LESSON THE TV 第01話");
        assert!(happy_lesson.contains(&("☆".to_string(), "B-TITLE".to_string())));
        let idolmaster = labels_for("[CASO&SumiSora][THE_IDOLM@STER_CINDERELLA_GIRLS][07.5_SP]");
        assert!(idolmaster.contains(&("@".to_string(), "B-TITLE".to_string())));
        let soul_taker = labels_for("[AI-Raws] THE SOUL TAKER～魂狩～ #01 (HEVC 1312x720)");
        assert!(soul_taker.contains(&("～".to_string(), "B-TITLE".to_string())));
        let mayoi = labels_for("[Snow-Raws] 迷家[マヨイガ] 第01話");
        assert!(mayoi.contains(&("迷家".to_string(), "B-TITLE".to_string())));
        assert!(mayoi.contains(&("マヨイガ".to_string(), "B-TITLE".to_string())));

        let conan_time = labels_for("【蓝色狂想】名侦探柯南TV版第036集-周一晚上7点半杀人事件");
        assert!(conan_time.contains(&("036".to_string(), "B-EPISODE".to_string())));
        assert!(!conan_time.contains(&("7".to_string(), "B-EPISODE".to_string())));
        let zom =
            labels_for("[Nekomoe kissaten&VCB-Studio] Zom 100 [Animatics02][Ma10p_1080p][x265]");
        assert!(zom.contains(&("100".to_string(), "B-TITLE".to_string())));
        assert!(!zom.contains(&("100".to_string(), "B-EPISODE".to_string())));
        assert!(zom.contains(&("Animatics02".to_string(), "B-SPECIAL".to_string())));

        let sky = labels_for("[Skytree][海贼王][One_Piece][918][GB_JP][1080P]");
        assert!(sky.contains(&("One".to_string(), "B-TITLE".to_string())));
        assert!(!sky.contains(&("海贼王".to_string(), "B-TITLE".to_string())));
        assert!(sky.contains(&("918".to_string(), "B-EPISODE".to_string())));
    }

    #[test]
    fn updated_python_alignment_regressions() {
        let original = "The New Woody Woodpecker Show (Season 1-4) (1999-2002) WEB-DL 720p [Hurtom]/Season 4/E07 - The New Woody Woodpecker Show (Season 1-4) (1999-2002) WEB-DL 720p";
        let (trimmed, was_trimmed) = training_filename_for(original);
        assert!(was_trimmed);
        assert_eq!(
            trimmed,
            "Season 4/E07 - The New Woody Woodpecker Show (Season 1-4) (1999-2002) WEB-DL 720p"
        );
        let pokemon = "Pokémon Season 2 - Orange League [Ep. 83-118]/Pokemon - 084 - OL002 - A Scare in the Air [DVD][PM-Dragon-x264-AC3][00270AC8]";
        let (trimmed_pokemon, pokemon_was_trimmed) = training_filename_for(pokemon);
        assert!(pokemon_was_trimmed);
        assert_eq!(
            trimmed_pokemon,
            "Pokemon - 084 - OL002 - A Scare in the Air [DVD][PM-Dragon-x264-AC3][00270AC8]"
        );
        let woody = labels_for(&trimmed);
        assert!(woody.contains(&("4".to_string(), "B-SEASON".to_string())));
        assert!(woody.contains(&("E".to_string(), "O".to_string())));
        assert!(woody.contains(&("07".to_string(), "B-EPISODE".to_string())));
        assert!(woody.contains(&("The".to_string(), "B-TITLE".to_string())));
        assert!(woody.contains(&("Show".to_string(), "B-TITLE".to_string())));
        assert!(!woody.contains(&("1999".to_string(), "B-EPISODE".to_string())));

        let group = labels_for("[DBD-Raws][Title][01][1080P]");
        assert!(group.contains(&("-".to_string(), "B-GROUP".to_string())));
        let amp_group = labels_for("[SumiSora&CASO][Title][01][1080P]");
        assert!(amp_group.contains(&("&".to_string(), "B-GROUP".to_string())));

        let cjk_season =
            labels_for("[DBD-Raws][魔道祖师 第一季][08][1080P][BDRip][HEVC-10bit][FLAC]");
        assert!(cjk_season.contains(&("魔道祖师".to_string(), "B-TITLE".to_string())));
        assert!(cjk_season.contains(&("第一季".to_string(), "B-SEASON".to_string())));
        assert!(!cjk_season.contains(&("第一季".to_string(), "B-TITLE".to_string())));

        let (trimmed, was_trimmed) =
            training_filename_for("12/小剧场/[LKSUB][KAGE-JITSU!][01][GB][720P]");
        assert!(was_trimmed);
        assert_eq!(trimmed, "[LKSUB][KAGE-JITSU!][01][GB][720P]");
        let (key, _, _, _) = template_key_for_filename(&trimmed);
        assert_eq!(
            key,
            "BRACKET_TEXT BRACKET_TEXT BRACKET_EPISODE BRACKET_LANG BRACKET_RESOLUTION"
        );

        let short = labels_for("[Snow-Raws] R-15 CM&PV12 (BD 1920x1080 HEVC-YUV420P10 FLAC)");
        assert!(short.contains(&("R".to_string(), "B-TITLE".to_string())));
        assert!(short.contains(&("-".to_string(), "B-TITLE".to_string())));
        assert!(short.contains(&("15".to_string(), "B-TITLE".to_string())));
        assert!(!short.contains(&("15".to_string(), "B-EPISODE".to_string())));

        let short_before_episode =
            labels_for("[Snow-Raws] R-15 第01話 (BD 1920x1080 HEVC-YUV420P10 FLAC)");
        assert!(short_before_episode.contains(&("R".to_string(), "B-TITLE".to_string())));
        assert!(short_before_episode.contains(&("-".to_string(), "B-TITLE".to_string())));
        assert!(short_before_episode.contains(&("15".to_string(), "B-TITLE".to_string())));
        assert!(short_before_episode.contains(&("01".to_string(), "B-EPISODE".to_string())));
        assert!(!short_before_episode.contains(&("15".to_string(), "B-EPISODE".to_string())));

        let avatar = "Avatar The Last Airbender S2/Avatar The Last Airbender S2 14 [1080p]";
        let (trimmed, was_trimmed) = training_filename_for(avatar);
        assert!(was_trimmed);
        assert_eq!(trimmed, "Avatar The Last Airbender S2 14 [1080p]");

        let tintin = "Adventures of Tintin (1991) Season 1-3 S01-S03 (1080p BluRay x265 HEVC 10bit EAC3 2.0 Garshasp)/Season 1/Adventures of Tintin (1991) - S01E06 - Cigars of the Pharaoh (Part 1) (1080p BluRay x265 Garshasp)";
        let (trimmed, was_trimmed) = training_filename_for(tintin);
        assert!(was_trimmed);
        assert_eq!(
            trimmed,
            "Adventures of Tintin (1991) - S01E06 - Cigars of the Pharaoh (Part 1) (1080p BluRay x265 Garshasp)"
        );
        let (key, _, _, _) = template_key_for_filename(&trimmed);
        assert_eq!(
            key,
            "TEXT SEP TEXT SEP TEXT SEP BRACKET_DATE SEP SXE SEP TEXT SEP TEXT SEP TEXT SEP TEXT SEP BRACKET_TEXT SEP BRACKET_TEXT"
        );

        let bocchi = "Bocchi the Rock S01 孤獨搖滾！第一季 [Taiwanese Hokkien Dub][臺灣閩南語配音]/Bocchi the Rock S01 孤獨搖滾！第一季 [Taiwanese Hokkien Dub][Hàn-jī Hardsub][臺灣閩南語配音][漢字字幕]/Bocchi the Rock! 孤獨搖滾！S01E01「孤獨反輾轉」";
        let (leaf_key, _, _, _) =
            template_key_for_filename("Bocchi the Rock! 孤獨搖滾！S01E01「孤獨反輾轉」");
        assert_eq!(leaf_key, "TEXT SEP TEXT SEP TEXT SEP TEXT SXE TEXT");
        assert!(filename_has_title(
            "Bocchi the Rock! 孤獨搖滾！S01E01「孤獨反輾轉」"
        ));
        let (trimmed, was_trimmed) = training_filename_for(bocchi);
        assert!(was_trimmed);
        assert_eq!(trimmed, "Bocchi the Rock! 孤獨搖滾！S01E01「孤獨反輾轉」");
        let (key, _, _, _) = template_key_for_filename(&trimmed);
        assert_eq!(key, "TEXT SEP TEXT SEP TEXT SEP TEXT SXE TEXT");

        let usagi = "Gochuumon wa Usagi Desuka-60fps/Gochuumon wa Usagi Desuka S1/Usagi S1[01][60fps][8bit_1080p][x265_flac]";
        let (trimmed, was_trimmed) = training_filename_for(usagi);
        assert!(was_trimmed);
        assert_eq!(trimmed, "Usagi S1[01][60fps][8bit_1080p][x265_flac]");
        let (key, _, _, _) = template_key_for_filename(&trimmed);
        assert_eq!(
            key,
            "TEXT SEP SEASON BRACKET_EPISODE BRACKET_TEXT BRACKET_MEDIA_BLOCK BRACKET_MEDIA"
        );

        let woody_parent =
            "Season 4/E07 - The New Woody Woodpecker Show (Season 1-4) (1999-2002) WEB-DL 720p";
        let (trimmed, was_trimmed) = training_filename_for(&format!("Batch/{woody_parent}"));
        assert!(was_trimmed);
        assert_eq!(trimmed, woody_parent);

        let volume =
            labels_for("[Snow-Raws] 生徒会役員共 Vol.01 MENU02 (BD 1920x1080 HEVC-YUV420P10 FLAC)");
        assert!(volume.contains(&("生徒会役員共".to_string(), "B-TITLE".to_string())));
        assert!(volume.contains(&("Vol".to_string(), "B-SPECIAL".to_string())));
        assert!(volume.contains(&("01".to_string(), "B-SPECIAL".to_string())));
        assert!(volume.contains(&("MENU02".to_string(), "B-SPECIAL".to_string())));
        assert!(!volume.contains(&("01".to_string(), "B-EPISODE".to_string())));

        let numeric_title =
            labels_for("3000.Leagues.in.Search.of.Mother.S01E01.1080p.WEB-DL.H.264-D00oo00M");
        assert!(numeric_title.contains(&("3000".to_string(), "B-TITLE".to_string())));
        assert!(numeric_title.contains(&("01".to_string(), "B-SEASON".to_string())));
        assert!(numeric_title.contains(&("01".to_string(), "B-EPISODE".to_string())));
        assert!(numeric_title.contains(&("1080p".to_string(), "B-RESOLUTION".to_string())));
        assert!(numeric_title.contains(&("H".to_string(), "B-SOURCE".to_string())));
        assert!(numeric_title.contains(&("264".to_string(), "B-SOURCE".to_string())));
        assert!(!numeric_title.contains(&("264".to_string(), "B-EPISODE".to_string())));

        let media_block =
            labels_for("[Kamigami] Kantai Collection - 06v2 [1920×1080 x264 AAC Sub(Chs,Cht,Jap)]");
        assert!(media_block.contains(&("1920".to_string(), "B-RESOLUTION".to_string())));
        assert!(media_block.contains(&("1080".to_string(), "B-RESOLUTION".to_string())));
        assert!(media_block.contains(&("x264".to_string(), "B-SOURCE".to_string())));
        assert!(media_block.contains(&("Chs".to_string(), "B-SOURCE".to_string())));
    }
}