#!/usr/bin/env python3
"""CLI entry point for the repository analyzer."""

import argparse
import json
import os
import re
import sys
from pathlib import Path

# Load .env from project root
_env = Path(__file__).parent / ".env"
if _env.exists():
    for _line in _env.read_text(encoding="utf-8").splitlines():
        _line = _line.strip()
        if _line and not _line.startswith("#") and "=" in _line:
            _k, _, _v = _line.partition("=")
            os.environ.setdefault(_k.strip(), _v.strip())

from src.repo_analyzer import Config, analyze_full
from src.repo_analyzer.pdf_report import Lang, build_pdf_report
from src.repo_analyzer.report import build_text_report


def _resolve_keys(args) -> tuple[str, str, str]:
    openrouter_key = args.openrouter_key or os.environ.get("OPENROUTER_KEY", "")
    if not openrouter_key:
        print("Error: OpenRouter API key required. Use --openrouter-key or set OPENROUTER_KEY.", file=sys.stderr)
        sys.exit(1)
    github_token = getattr(args, "token", None) or os.environ.get("GITHUB_TOKEN", "")
    model = getattr(args, "model", None) or os.environ.get("OPENROUTER_MODEL", "openai/gpt-4o-mini")
    return openrouter_key, github_token, model


def _extract_repo_url(repo_txt: str) -> str | None:
    """Return the first https URL found in repo.txt content."""
    urls = re.findall(r"https?://\S+", repo_txt)
    if not urls:
        return None
    return urls[0].rstrip(".,)")


def _load_claims(path: Path) -> list | None:
    data = json.loads(path.read_text(encoding="utf-8"))
    if isinstance(data, dict) and "result" in data:
        return data["result"]
    if isinstance(data, list):
        return data
    return None


def _save_pdfs(
    report: dict,
    langs: list[Lang],
    out_dir: Path,
    stem: str,
    openrouter_key: str,
    model: str,
    paper_name: str | None = None,
) -> None:
    """Generate and write PDF report(s) for each requested language."""
    for lang in langs:
        pdf_bytes = build_pdf_report(
            report,
            lang=lang,
            openrouter_key=openrouter_key if lang == "ru" else None,
            model=model if lang == "ru" else None,
            paper_name=paper_name,
        )
        pdf_path = out_dir / f"{stem}_{lang}.pdf"
        pdf_path.write_bytes(pdf_bytes)
        print(f"         pdf ({lang})  -> {pdf_path.name}", file=sys.stderr)


# ── single run ────────────────────────────────────────────────────────────────


def cmd_run(args) -> None:
    openrouter_key, github_token, model = _resolve_keys(args)

    config = Config(
        repo_url=args.repo,
        openrouter_key=openrouter_key,
        github_token=github_token or None,
        model=model,
    )

    paper_sections = None
    pre_extracted_claims = None
    paper_name = None

    if args.claims_json:
        claims_path = Path(args.claims_json)
        pre_extracted_claims = _load_claims(claims_path)
        if pre_extracted_claims is None:
            print("Error: unrecognised claims JSON format.", file=sys.stderr)
            sys.exit(1)
        # derive paper name from filename, e.g. "sheet_1_14_05_Галин_claims_result" → "sheet_1_14_05_Галин"
        paper_name = re.sub(r"_claims_result$", "", claims_path.stem)
    elif args.paper_sections:
        paper_sections = json.loads(Path(args.paper_sections).read_text(encoding="utf-8"))

    try:
        report = analyze_full(config, paper_sections=paper_sections, pre_extracted_claims=pre_extracted_claims)
    except Exception as e:
        print(f"Error: {e}", file=sys.stderr)
        sys.exit(1)

    out_dir = Path(args.output_dir)
    out_dir.mkdir(parents=True, exist_ok=True)
    stem = f"{paper_name}_repo_analysis" if paper_name else "report"
    json_path = out_dir / f"{stem}.json"
    txt_path = out_dir / f"{stem}.txt"

    with open(json_path, "w", encoding="utf-8") as f:
        json.dump(report, f, ensure_ascii=False, indent=2)
    with open(txt_path, "w", encoding="utf-8") as f:
        f.write(build_text_report(report, paper_name=paper_name))

    print(f"Saved: {json_path}", file=sys.stderr)
    print(f"       {txt_path}", file=sys.stderr)

    if args.langs:
        _save_pdfs(report, args.langs, out_dir, stem, openrouter_key, model, paper_name=paper_name)

    if not args.json_only:
        print("\n" + build_text_report(report, paper_name=paper_name) + "\n")
    print(json.dumps(report, ensure_ascii=False, indent=2))


# ── batch run ─────────────────────────────────────────────────────────────────


def cmd_batch(args) -> None:
    openrouter_key, github_token, model = _resolve_keys(args)

    data_dir = Path(args.data_dir)
    if not data_dir.exists():
        print(f"Error: data directory '{data_dir}' does not exist.", file=sys.stderr)
        sys.exit(1)

    results_root = Path(args.results_dir) if args.results_dir else data_dir / "results"
    results_root.mkdir(parents=True, exist_ok=True)

    folders = sorted(f for f in data_dir.iterdir() if f.is_dir() and f.name.startswith("sheet_"))
    print(f"Found {len(folders)} student folders in {data_dir}", file=sys.stderr)
    print(f"Results -> {results_root}\n", file=sys.stderr)

    ok = skipped = errors = 0

    for folder in folders:
        name = folder.name
        out_dir = results_root / name
        out_json = out_dir / f"{name}_repo_analysis.json"

        # ── repo URL ──────────────────────────────────────────────────────────
        repo_file = folder / "repo.txt"
        if not repo_file.exists():
            print(f"  SKIP  {name}: no repo.txt", file=sys.stderr)
            skipped += 1
            continue

        repo_url = _extract_repo_url(repo_file.read_text(encoding="utf-8"))
        if not repo_url:
            print(f"  SKIP  {name}: no valid URL in repo.txt", file=sys.stderr)
            skipped += 1
            continue

        # ── claims JSON ───────────────────────────────────────────────────────
        claims_file = folder / f"{name}_claims_result.json"
        if not claims_file.exists():
            print(f"  SKIP  {name}: no claims JSON", file=sys.stderr)
            skipped += 1
            continue

        claims = _load_claims(claims_file)
        if claims is None:
            print(f"  SKIP  {name}: unrecognised claims format", file=sys.stderr)
            skipped += 1
            continue

        # ── skip already analyzed (unless --force) ────────────────────────────
        if out_json.exists() and not args.force:
            missing_pdfs = (
                [lang for lang in args.langs if not (out_dir / f"{name}_repo_analysis_{lang}.pdf").exists()]
                if args.langs
                else []
            )
            if not missing_pdfs:
                print(f"  SKIP  {name}: already analyzed (use --force to rerun)", file=sys.stderr)
                skipped += 1
                continue
            # Analysis done, only PDFs missing — load cached report
            print(f"  PDF   {name}: generating missing PDF(s): {missing_pdfs}", file=sys.stderr)
            report = json.loads(out_json.read_text(encoding="utf-8"))
            _save_pdfs(report, missing_pdfs, out_dir, f"{name}_repo_analysis", openrouter_key, model, paper_name=name)
            ok += 1
            continue

        print(f"  RUN   {name}  ({len(claims)} claims)  {repo_url[:70]}", file=sys.stderr)

        config = Config(
            repo_url=repo_url,
            openrouter_key=openrouter_key,
            github_token=github_token or None,
            model=model,
        )

        try:
            report = analyze_full(config, pre_extracted_claims=claims)
        except Exception as e:
            print(f"  ERROR {name}: {e}", file=sys.stderr)
            errors += 1
            continue

        out_dir.mkdir(parents=True, exist_ok=True)
        out_txt = out_dir / f"{name}_repo_analysis.txt"
        with open(out_json, "w", encoding="utf-8") as f:
            json.dump(report, f, ensure_ascii=False, indent=2)
        with open(out_txt, "w", encoding="utf-8") as f:
            f.write(build_text_report(report))

        score = report.get("summary", {}).get("score", "?")
        print(f"         score={score}  -> {out_dir.name}/", file=sys.stderr)

        if args.langs:
            _save_pdfs(report, args.langs, out_dir, f"{name}_repo_analysis", openrouter_key, model, paper_name=name)

        ok += 1

    print(f"\nDone: {ok} analyzed, {skipped} skipped, {errors} errors", file=sys.stderr)


# ── argument parser ───────────────────────────────────────────────────────────


def _add_pdf_args(p: argparse.ArgumentParser) -> None:
    p.add_argument(
        "--pdf",
        dest="langs",
        nargs="+",
        metavar="LANG",
        choices=["en", "ru", "both"],
        default=[],
        help=("Generate PDF report(s). Pass one or more of: en  ru  both. " "Example: --pdf en ru   or   --pdf both"),
    )


def main() -> None:
    parser = argparse.ArgumentParser(description="Analyze GitHub repositories and verify claims against code.")

    # shared flags
    shared = argparse.ArgumentParser(add_help=False)
    shared.add_argument("--token", default=None, help="GitHub token (or GITHUB_TOKEN env var)")
    shared.add_argument(
        "--openrouter-key", default=None, dest="openrouter_key", help="OpenRouter API key (or OPENROUTER_KEY env var)"
    )
    shared.add_argument("--model", default=None, help="OpenRouter model ID")

    sub = parser.add_subparsers(dest="command", required=True)

    # ── run ───────────────────────────────────────────────────────────────────
    p_run = sub.add_parser("run", parents=[shared], help="Analyze a single repository.")
    p_run.add_argument("--repo", required=True, help="GitHub repository URL")
    p_run.add_argument(
        "--paper-sections",
        default=None,
        dest="paper_sections",
        metavar="FILE",
        help="Sections JSON from parse_pdf_with_marker.py (enables claim extraction).",
    )
    p_run.add_argument(
        "--claims-json",
        default=None,
        dest="claims_json",
        metavar="FILE",
        help="Pre-extracted claims JSON (skips extraction, goes straight to verification).",
    )
    p_run.add_argument(
        "--output-dir", default="./results", dest="output_dir", help="Directory to save results (default: ./results)"
    )
    p_run.add_argument(
        "--json-only", action="store_true", dest="json_only", help="Print JSON only, skip human-readable text"
    )
    _add_pdf_args(p_run)
    p_run.set_defaults(func=cmd_run)

    # ── batch ─────────────────────────────────────────────────────────────────
    p_batch = sub.add_parser(
        "batch",
        parents=[shared],
        help="Bulk-analyze all student folders in a data directory. "
        "Each folder must contain repo.txt and *_claims_result.json.",
    )
    p_batch.add_argument(
        "--data-dir",
        default="./data",
        dest="data_dir",
        help="Root data directory with student folders (default: ./data)",
    )
    p_batch.add_argument(
        "--results-dir", default=None, dest="results_dir", help="Where to save results (default: <data-dir>/results)"
    )
    p_batch.add_argument(
        "--force", action="store_true", help="Re-analyze folders that already have a repo_analysis.json"
    )
    _add_pdf_args(p_batch)
    p_batch.set_defaults(func=cmd_batch)

    args = parser.parse_args()

    # Expand "both" → ["en", "ru"] and deduplicate
    if hasattr(args, "langs") and args.langs:
        expanded = []
        for lang in args.langs:
            expanded += ["en", "ru"] if lang == "both" else [lang]
        args.langs = list(dict.fromkeys(expanded))  # deduplicate, preserve order

    args.func(args)


if __name__ == "__main__":
    main()