#!/usr/bin/env python3
import argparse
import json
from pathlib import Path
from typing import Dict, List, Optional, Tuple


USER_INSTRUCTION = (
    "Determine whether the claim is SUPPORTS, CONTRADICTS, or NOT ENOUGH INFORMATION "
    "based only on the provided abstract. Use sentence indices as rationale evidence."
)

LABEL_MAP = {
    "SUPPORT": "SUPPORTS",
    "CONTRADICT": "CONTRADICTS",
}


def parse_args() -> argparse.Namespace:
    parser = argparse.ArgumentParser(
        description="Prepare SciFact Unsloth chat-format train/validation datasets."
    )
    parser.add_argument(
        "--corpus-jsonl",
        type=Path,
        default=Path("/d/hpc/projects/FRI/DL/Scholar/raw_downloads/scifact/data/corpus.jsonl"),
    )
    parser.add_argument(
        "--claims-train-jsonl",
        type=Path,
        default=Path("/d/hpc/projects/FRI/DL/Scholar/raw_downloads/scifact/data/claims_train.jsonl"),
    )
    parser.add_argument(
        "--claims-dev-jsonl",
        type=Path,
        default=Path("/d/hpc/projects/FRI/DL/Scholar/raw_downloads/scifact/data/claims_dev.jsonl"),
    )
    parser.add_argument(
        "--output-dir",
        type=Path,
        default=Path("/d/hpc/projects/FRI/DL/Scholar/prepared_datasets/scifact_unsloth"),
    )
    return parser.parse_args()


def read_jsonl(path: Path) -> List[Dict]:
    rows: List[Dict] = []
    with path.open("r", encoding="utf-8") as f:
        for line in f:
            line = line.strip()
            if not line:
                continue
            rows.append(json.loads(line))
    return rows


def build_corpus_lookup(corpus_rows: List[Dict]) -> Dict[int, Dict]:
    lookup: Dict[int, Dict] = {}
    for row in corpus_rows:
        lookup[int(row["doc_id"])] = row
    return lookup


def format_abstract_with_indices(sentences: List[str]) -> str:
    lines = []
    for i, sent in enumerate(sentences):
        sent = (sent or "").strip()
        lines.append(f"[{i}] {sent}")
    return "\n".join(lines)


def get_rationale_texts(sentences: List[str], idxs: List[int]) -> List[str]:
    out = []
    for i in idxs:
        if isinstance(i, int) and 0 <= i < len(sentences):
            txt = (sentences[i] or "").strip()
            if txt:
                out.append(txt)
    return out


def build_user_text(claim: str, title: str, abstract_indexed: str) -> str:
    return (
        f"{USER_INSTRUCTION}\n\n"
        f"Claim: {claim}\n\n"
        f"Document title: {title}\n\n"
        f"Abstract sentences:\n{abstract_indexed}"
    )


def build_assistant_text(label: str, rationale_ids: List[int], rationale_texts: List[str]) -> str:
    if label == "NOT ENOUGH INFORMATION":
        return (
            "Label: NOT ENOUGH INFORMATION\n"
            "Rationale sentence ids: []\n"
            "Explanation: The provided abstract does not contain direct evidence to support or contradict the claim."
        )
    evidence_text = " ".join(rationale_texts).strip()
    verb = "supports" if label == "SUPPORTS" else "contradicts"
    return (
        f"Label: {label}\n"
        f"Rationale sentence ids: {rationale_ids}\n"
        f"Explanation: Evidence states: \"{evidence_text}\". This {verb} the claim."
    )


def row_from_evidence(
    split: str,
    claim_row: Dict,
    doc_id: int,
    evidence_entry: Dict,
    corpus_lookup: Dict[int, Dict],
    variant: str,
) -> Optional[Dict]:
    doc = corpus_lookup.get(doc_id)
    if doc is None:
        return None
    title = doc.get("title", "")
    abstract = doc.get("abstract", []) or []
    rationale_ids = evidence_entry.get("sentences", []) or []
    label_raw = evidence_entry.get("label", "")
    label = LABEL_MAP.get(label_raw, label_raw)
    if label not in {"SUPPORTS", "CONTRADICTS"}:
        return None

    abstract_indexed = format_abstract_with_indices(abstract)
    rationale_texts = get_rationale_texts(abstract, rationale_ids)
    user_text = build_user_text(claim=claim_row["claim"], title=title, abstract_indexed=abstract_indexed)
    assistant_text = build_assistant_text(label=label, rationale_ids=rationale_ids, rationale_texts=rationale_texts)

    return {
        "messages": [
            {"role": "user", "content": [{"type": "text", "text": user_text}]},
            {"role": "assistant", "content": [{"type": "text", "text": assistant_text}]},
        ],
        "meta": {
            "dataset": "scifact",
            "split": split,
            "claim_id": claim_row["id"],
            "doc_id": doc_id,
            "label": label,
            "evidence_sentence_ids": rationale_ids,
            "cited_doc_ids": claim_row.get("cited_doc_ids", []),
            "variant": variant,
        },
    }


def row_for_nei(split: str, claim_row: Dict, corpus_lookup: Dict[int, Dict]) -> Dict:
    cited_doc_ids = claim_row.get("cited_doc_ids", []) or []
    doc_id = cited_doc_ids[0] if cited_doc_ids else None
    doc = corpus_lookup.get(int(doc_id)) if doc_id is not None else None
    if doc is not None:
        title = doc.get("title", "")
        abstract = doc.get("abstract", []) or []
        abstract_indexed = format_abstract_with_indices(abstract)
        user_text = build_user_text(claim=claim_row["claim"], title=title, abstract_indexed=abstract_indexed)
        variant = "nei_with_cited_abstract"
    else:
        user_text = (
            f"{USER_INSTRUCTION}\n\n"
            f"Claim: {claim_row['claim']}\n\n"
            "No cited abstract is available in the corpus for this claim."
        )
        variant = "nei_no_corpus_doc"

    assistant_text = build_assistant_text(
        label="NOT ENOUGH INFORMATION",
        rationale_ids=[],
        rationale_texts=[],
    )
    return {
        "messages": [
            {"role": "user", "content": [{"type": "text", "text": user_text}]},
            {"role": "assistant", "content": [{"type": "text", "text": assistant_text}]},
        ],
        "meta": {
            "dataset": "scifact",
            "split": split,
            "claim_id": claim_row["id"],
            "doc_id": doc_id if doc_id is not None else "",
            "label": "NOT ENOUGH INFORMATION",
            "evidence_sentence_ids": [],
            "cited_doc_ids": cited_doc_ids,
            "variant": variant,
        },
    }


def build_rows(split: str, claim_rows: List[Dict], corpus_lookup: Dict[int, Dict]) -> List[Dict]:
    rows: List[Dict] = []
    for claim_row in claim_rows:
        evidence = claim_row.get("evidence", {}) or {}
        if not evidence:
            rows.append(row_for_nei(split, claim_row, corpus_lookup))
            continue

        emitted = 0
        for doc_id_str, rationale_list in evidence.items():
            doc_id = int(doc_id_str)
            for ev in rationale_list:
                row = row_from_evidence(
                    split=split,
                    claim_row=claim_row,
                    doc_id=doc_id,
                    evidence_entry=ev,
                    corpus_lookup=corpus_lookup,
                    variant="evidence_rationale",
                )
                if row is not None:
                    rows.append(row)
                    emitted += 1
        if emitted == 0:
            rows.append(row_for_nei(split, claim_row, corpus_lookup))
    return rows


def write_jsonl(path: Path, rows: List[Dict]) -> None:
    with path.open("w", encoding="utf-8") as f:
        for r in rows:
            f.write(json.dumps(r, ensure_ascii=False) + "\n")


def counts_by_label(rows: List[Dict]) -> Dict[str, int]:
    labels = ["SUPPORTS", "CONTRADICTS", "NOT ENOUGH INFORMATION"]
    return {label: sum(1 for r in rows if r["meta"]["label"] == label) for label in labels}


def main() -> None:
    args = parse_args()
    args.output_dir.mkdir(parents=True, exist_ok=True)

    corpus_rows = read_jsonl(args.corpus_jsonl)
    train_claims = read_jsonl(args.claims_train_jsonl)
    dev_claims = read_jsonl(args.claims_dev_jsonl)
    corpus_lookup = build_corpus_lookup(corpus_rows)

    train_rows = build_rows("train", train_claims, corpus_lookup)
    dev_rows = build_rows("validation", dev_claims, corpus_lookup)

    train_out = args.output_dir / "train.jsonl"
    val_out = args.output_dir / "validation.jsonl"
    stats_out = args.output_dir / "stats.json"
    write_jsonl(train_out, train_rows)
    write_jsonl(val_out, dev_rows)

    stats = {
        "train": {
            "rows": len(train_rows),
            "label_counts": counts_by_label(train_rows),
        },
        "validation": {
            "rows": len(dev_rows),
            "label_counts": counts_by_label(dev_rows),
        },
        "paths": {
            "train_jsonl": str(train_out),
            "validation_jsonl": str(val_out),
            "stats_json": str(stats_out),
        },
    }
    with stats_out.open("w", encoding="utf-8") as f:
        json.dump(stats, f, ensure_ascii=False, indent=2)
    print(json.dumps(stats, ensure_ascii=False, indent=2))


if __name__ == "__main__":
    main()