#!/usr/bin/env python3
"""
Analyze downloaded Vietnamese Legal Corpus files
"""

import re
from pathlib import Path
from collections import defaultdict

import click
from rich.console import Console
from rich.table import Table

console = Console()

DATA_DIR = Path(__file__).parent.parent / "data"


def parse_front_matter(content: str) -> dict:
    """Parse YAML front matter from markdown file."""
    metadata = {}
    if content.startswith("---"):
        parts = content.split("---", 2)
        if len(parts) >= 3:
            for line in parts[1].strip().split("\n"):
                if ":" in line:
                    key, value = line.split(":", 1)
                    value = value.strip().strip('"')
                    metadata[key.strip()] = value
    return metadata


def analyze_file(filepath: Path) -> dict:
    """Analyze a single law file."""
    content = filepath.read_text(encoding="utf-8")
    size = filepath.stat().st_size

    metadata = parse_front_matter(content)

    # Check if content exists (after front matter)
    parts = content.split("---", 2)
    body = parts[2] if len(parts) >= 3 else ""

    has_content = len(body.strip()) > 200 and "*Nội dung chưa được tải xuống.*" not in body

    return {
        "filename": filepath.name,
        "title": metadata.get("title", "Unknown"),
        "type": metadata.get("type", "unknown"),
        "year": metadata.get("year", "unknown"),
        "document_number": metadata.get("document_number", ""),
        "url": metadata.get("url", ""),
        "size": size,
        "has_content": has_content,
        "content_length": len(body.strip()),
    }


@click.group()
def cli():
    """Analyze VLC corpus files."""
    pass


@cli.command()
def summary():
    """Show summary statistics."""
    if not DATA_DIR.exists():
        console.print("[red]Data directory not found[/red]")
        return

    files = list(DATA_DIR.glob("*.md"))

    stats = {
        "total": len(files),
        "with_content": 0,
        "without_content": 0,
        "codes": 0,
        "laws": 0,
        "total_size": 0,
        "by_year": defaultdict(int),
    }

    failed = []

    for f in files:
        info = analyze_file(f)
        stats["total_size"] += info["size"]

        if info["type"] == "code":
            stats["codes"] += 1
        else:
            stats["laws"] += 1

        stats["by_year"][info["year"]] += 1

        if info["has_content"]:
            stats["with_content"] += 1
        else:
            stats["without_content"] += 1
            failed.append(info)

    # Print summary
    console.print("[bold blue]VLC Corpus Analysis[/bold blue]\n")

    table = Table(title="Summary")
    table.add_column("Metric", style="cyan")
    table.add_column("Value", style="green")

    table.add_row("Total files", str(stats["total"]))
    table.add_row("Codes (Bộ luật)", str(stats["codes"]))
    table.add_row("Laws (Luật)", str(stats["laws"]))
    table.add_row("With content", f"{stats['with_content']} ✓")
    table.add_row("Without content", f"{stats['without_content']} ✗")
    table.add_row("Success rate", f"{stats['with_content']/stats['total']*100:.1f}%")
    table.add_row("Total size", f"{stats['total_size']/1024/1024:.1f} MB")

    console.print(table)

    # By year
    console.print("\n[bold]By Year:[/bold]")
    for year in sorted(stats["by_year"].keys(), reverse=True)[:10]:
        console.print(f"  {year}: {stats['by_year'][year]}")

    # Failed files
    if failed:
        console.print(f"\n[bold red]Files without content ({len(failed)}):[/bold red]")
        for info in failed:
            console.print(f"  - {info['filename']}")
            console.print(f"    Title: {info['title']}")
            console.print(f"    Doc#: {info['document_number']}")


@cli.command()
def failed():
    """List files that failed to download."""
    if not DATA_DIR.exists():
        console.print("[red]Data directory not found[/red]")
        return

    files = list(DATA_DIR.glob("*.md"))

    table = Table(title="Files Without Content")
    table.add_column("#", style="dim")
    table.add_column("Filename", style="cyan")
    table.add_column("Title", style="white")
    table.add_column("Year", style="green")
    table.add_column("Size", style="yellow")

    count = 0
    for f in sorted(files):
        info = analyze_file(f)
        if not info["has_content"]:
            count += 1
            table.add_row(
                str(count),
                info["filename"],
                info["title"][:40] + "..." if len(info["title"]) > 40 else info["title"],
                str(info["year"]),
                f"{info['size']} B"
            )

    if count > 0:
        console.print(table)
        console.print(f"\n[red]Total: {count} files without content[/red]")
    else:
        console.print("[green]All files have content![/green]")


@cli.command()
def success():
    """List files that were downloaded successfully."""
    if not DATA_DIR.exists():
        console.print("[red]Data directory not found[/red]")
        return

    files = list(DATA_DIR.glob("*.md"))

    table = Table(title="Successfully Downloaded Files")
    table.add_column("#", style="dim")
    table.add_column("Filename", style="cyan")
    table.add_column("Title", style="white")
    table.add_column("Size", style="green")

    count = 0
    for f in sorted(files, key=lambda x: x.stat().st_size, reverse=True):
        info = analyze_file(f)
        if info["has_content"]:
            count += 1
            if count <= 20:  # Show top 20
                table.add_row(
                    str(count),
                    info["filename"],
                    info["title"][:50] + "..." if len(info["title"]) > 50 else info["title"],
                    f"{info['size']/1024:.1f} KB"
                )

    console.print(table)
    if count > 20:
        console.print(f"\n... and {count - 20} more files")
    console.print(f"\n[green]Total: {count} files with content[/green]")


@cli.command()
@click.argument("pattern", default="")
def search(pattern: str):
    """Search files by name or title."""
    if not DATA_DIR.exists():
        console.print("[red]Data directory not found[/red]")
        return

    files = list(DATA_DIR.glob("*.md"))
    pattern = pattern.lower()

    results = []
    for f in files:
        info = analyze_file(f)
        if pattern in info["filename"].lower() or pattern in info["title"].lower():
            results.append(info)

    if results:
        table = Table(title=f"Search Results: '{pattern}'")
        table.add_column("Filename", style="cyan")
        table.add_column("Title", style="white")
        table.add_column("Content", style="green")
        table.add_column("Size", style="yellow")

        for info in results:
            table.add_row(
                info["filename"],
                info["title"][:40],
                "✓" if info["has_content"] else "✗",
                f"{info['size']/1024:.1f} KB"
            )

        console.print(table)
    else:
        console.print(f"[yellow]No files found matching '{pattern}'[/yellow]")


REQUIRED_FIELDS = ["title", "type", "year", "document_number"]
OPTIONAL_FIELDS = ["title_en", "effective_date", "status", "url", "downloaded_at"]


def validate_front_matter(filepath: Path) -> dict:
    """Validate front matter of a file and return issues."""
    content = filepath.read_text(encoding="utf-8")
    issues = []
    metadata = {}

    # Check if file starts with front matter
    if not content.startswith("---"):
        issues.append("Missing front matter (no opening ---)")
        return {"filename": filepath.name, "issues": issues, "metadata": metadata}

    parts = content.split("---", 2)
    if len(parts) < 3:
        issues.append("Invalid front matter (no closing ---)")
        return {"filename": filepath.name, "issues": issues, "metadata": metadata}

    # Parse front matter
    for line in parts[1].strip().split("\n"):
        if ":" in line:
            key, value = line.split(":", 1)
            key = key.strip()
            value = value.strip().strip('"')
            metadata[key] = value

    # Check required fields
    for field in REQUIRED_FIELDS:
        if field not in metadata:
            issues.append(f"Missing required field: {field}")
        elif not metadata[field] or metadata[field] in ("Unknown", "unknown", ""):
            issues.append(f"Empty or invalid value for: {field}")

    # Validate type field
    if metadata.get("type") and metadata["type"] not in ("code", "law"):
        issues.append(f"Invalid type: {metadata['type']} (should be 'code' or 'law')")

    # Validate year field
    year = metadata.get("year", "")
    if year and not year.isdigit():
        issues.append(f"Invalid year format: {year}")
    elif year and (int(year) < 1945 or int(year) > 2030):
        issues.append(f"Year out of range: {year}")

    # Check filename matches metadata
    expected_prefix = "code" if metadata.get("type") == "code" else "law"
    if not filepath.name.startswith(f"{expected_prefix}-"):
        issues.append(f"Filename prefix mismatch: expected '{expected_prefix}-'")

    if year and f"-{year}-" not in filepath.name:
        issues.append(f"Year in filename doesn't match metadata: {year}")

    return {"filename": filepath.name, "issues": issues, "metadata": metadata}


@cli.command()
def validate():
    """Validate front matter of all files."""
    if not DATA_DIR.exists():
        console.print("[red]Data directory not found[/red]")
        return

    files = list(DATA_DIR.glob("*.md"))
    invalid_files = []

    for f in sorted(files):
        result = validate_front_matter(f)
        if result["issues"]:
            invalid_files.append(result)

    if invalid_files:
        table = Table(title="Files with Invalid Front Matter")
        table.add_column("#", style="dim")
        table.add_column("Filename", style="cyan")
        table.add_column("Issues", style="red")

        for i, item in enumerate(invalid_files, 1):
            table.add_row(
                str(i),
                item["filename"],
                "\n".join(item["issues"])
            )

        console.print(table)
        console.print(f"\n[red]Total: {len(invalid_files)} files with issues[/red]")
    else:
        console.print("[green]All files have valid front matter![/green]")

    # Summary
    console.print(f"\n[bold]Validation Summary:[/bold]")
    console.print(f"  Total files: {len(files)}")
    console.print(f"  Valid: {len(files) - len(invalid_files)}")
    console.print(f"  Invalid: {len(invalid_files)}")


@cli.command()
@click.argument("filename", required=False)
def inspect(filename: str):
    """Inspect front matter of a specific file or show all fields."""
    if not DATA_DIR.exists():
        console.print("[red]Data directory not found[/red]")
        return

    if filename:
        # Inspect single file
        filepath = DATA_DIR / filename
        if not filepath.exists():
            # Try to find matching file
            matches = list(DATA_DIR.glob(f"*{filename}*"))
            if matches:
                filepath = matches[0]
            else:
                console.print(f"[red]File not found: {filename}[/red]")
                return

        result = validate_front_matter(filepath)
        console.print(f"\n[bold]File: {result['filename']}[/bold]\n")

        table = Table(title="Front Matter")
        table.add_column("Field", style="cyan")
        table.add_column("Value", style="white")
        table.add_column("Status", style="green")

        for field in REQUIRED_FIELDS + OPTIONAL_FIELDS:
            value = result["metadata"].get(field, "")
            if field in REQUIRED_FIELDS:
                status = "✓" if value and value not in ("Unknown", "unknown") else "✗ required"
            else:
                status = "✓" if value else "-"
            table.add_row(field, str(value)[:50], status)

        console.print(table)

        if result["issues"]:
            console.print("\n[bold red]Issues:[/bold red]")
            for issue in result["issues"]:
                console.print(f"  - {issue}")
    else:
        # Show field statistics
        files = list(DATA_DIR.glob("*.md"))
        field_stats = defaultdict(int)

        for f in files:
            result = validate_front_matter(f)
            for field in REQUIRED_FIELDS + OPTIONAL_FIELDS:
                if result["metadata"].get(field):
                    field_stats[field] += 1

        table = Table(title="Front Matter Field Statistics")
        table.add_column("Field", style="cyan")
        table.add_column("Present", style="green")
        table.add_column("Missing", style="red")
        table.add_column("Coverage", style="yellow")

        for field in REQUIRED_FIELDS + OPTIONAL_FIELDS:
            present = field_stats[field]
            missing = len(files) - present
            coverage = f"{present/len(files)*100:.1f}%"
            req = " (required)" if field in REQUIRED_FIELDS else ""
            table.add_row(f"{field}{req}", str(present), str(missing), coverage)

        console.print(table)


@cli.command()
def export_failed():
    """Export failed files to retry list."""
    if not DATA_DIR.exists():
        console.print("[red]Data directory not found[/red]")
        return

    files = list(DATA_DIR.glob("*.md"))

    failed = []
    for f in files:
        info = analyze_file(f)
        if not info["has_content"]:
            failed.append({
                "filename": info["filename"],
                "title": info["title"],
                "document_number": info["document_number"],
            })

    if failed:
        output = DATA_DIR.parent / "failed_downloads.txt"
        with open(output, "w", encoding="utf-8") as f:
            for item in failed:
                f.write(f"{item['filename']}\t{item['title']}\t{item['document_number']}\n")

        console.print(f"[green]Exported {len(failed)} failed files to {output}[/green]")
    else:
        console.print("[green]No failed files to export[/green]")


if __name__ == "__main__":
    cli()