#!/usr/bin/env python3
"""CASAN Plan-10 traceability matrix generator/gate.

Parses FR-* requirements from apps/okr/domain/input/okr-requirement.md and checks each
requirement has at least one existing code file and one existing test file.
"""
import argparse
import json
import os
import re
import sys
from datetime import datetime, timezone


FR_RE = re.compile(r"\|\s*(FR-\d+)\s*\|\s*([^|]+?)\s*\|")


def project_root() -> str:
    # Plan-01: harness code lives in packages/casan-harness/; a fixed __file__ parent
    # depth lands on the package, not the app. Walk UP for the `.specify` state marker
    # so this resolves the app root whether invoked via packages/... or the .specify facade.
    d = os.path.abspath(os.path.dirname(__file__))
    p = d
    while p != os.path.dirname(p):
        if os.path.isdir(os.path.join(p, ".specify")):
            return p
        p = os.path.dirname(p)
    return os.path.abspath(os.path.join(d, "..", "..", ".."))


def parse_requirements(path: str):
    seen = {}
    with open(path, encoding="utf-8") as f:
        for line in f:
            match = FR_RE.search(line)
            if not match:
                continue
            fr_id, name = match.groups()
            if fr_id not in seen:
                seen[fr_id] = {"id": fr_id, "name": " ".join(name.split())}
    return [seen[k] for k in sorted(seen)]


def normalize_entry(value):
    """Accept either a plain path string or an object with symbol/line refs.

    Backward compatible: a bare string behaves exactly as file-level tracing.
    Object form: {"file": "path", "symbols": ["name", ...], "lines": [n, ...]}.
    """
    if isinstance(value, str):
        return value, [], []
    if isinstance(value, dict):
        return value.get("file", ""), list(value.get("symbols", [])), list(value.get("lines", []))
    return "", [], []


def symbol_present(text: str, symbol: str) -> bool:
    """Symbol-level check: the symbol appears as a definition or reference.

    Covers common TS/JS/Python forms: `class X`, `function x`, `x(`, `const x`,
    `x =`, `x:` (method/property). Deliberately permissive but anchored on word
    boundaries so a substring alone does not count.
    """
    esc = re.escape(symbol)
    patterns = [
        rf"\b(?:function|class|interface|type|enum|const|let|var|def)\s+{esc}\b",
        rf"\b{esc}\s*[=:(]",
    ]
    return any(re.search(p, text) for p in patterns)


def resolve_files(root: str, values):
    """Resolve file existence plus optional symbol/line coverage.

    Returns present files, missing files, per-file symbol results, and the list
    of unsatisfied symbol/line references (which make the requirement FAIL).
    """
    present, missing = [], []
    symbol_results = []
    missing_symbols = []
    missing_lines = []
    for value in values or []:
        rel, symbols, lines = normalize_entry(value)
        if not rel:
            continue
        abs_path = os.path.join(root, rel)
        if not os.path.isfile(abs_path):
            missing.append(rel)
            for sym in symbols:
                missing_symbols.append(f"{rel}#{sym}")
            for ln in lines:
                missing_lines.append(f"{rel}:L{ln}")
            continue
        present.append(rel)
        if not symbols and not lines:
            continue
        with open(abs_path, encoding="utf-8", errors="replace") as fh:
            text = fh.read()
        total_lines = text.count("\n") + 1
        for sym in symbols:
            found = symbol_present(text, sym)
            symbol_results.append({"file": rel, "symbol": sym, "found": found})
            if not found:
                missing_symbols.append(f"{rel}#{sym}")
        for ln in lines:
            if not isinstance(ln, int) or ln < 1 or ln > total_lines:
                missing_lines.append(f"{rel}:L{ln}")
    return present, missing, symbol_results, missing_symbols, missing_lines


def main() -> int:
    root = project_root()
    ap = argparse.ArgumentParser()
    ap.add_argument("--requirements", default=os.path.join(root, "apps/okr/domain/input/okr-requirement.md"))
    ap.add_argument("--map", default=os.path.join(root, "apps/okr/domain/traceability-map.json"))
    ap.add_argument("--out", default=os.path.join(root, "docs/output/casan/traceability-matrix.json"))
    ap.add_argument("--gate", action="store_true")
    args = ap.parse_args()

    reqs = parse_requirements(args.requirements)
    with open(args.map, encoding="utf-8") as f:
        mapping = json.load(f)

    rows = []
    failures = []
    total_symbols = 0
    total_symbols_found = 0
    for req in reqs:
        entry = mapping.get(req["id"], {})
        code, missing_code, code_syms, code_missing_syms, code_missing_lines = resolve_files(
            root, entry.get("code", [])
        )
        tests, missing_tests, test_syms, test_missing_syms, test_missing_lines = resolve_files(
            root, entry.get("tests", [])
        )
        symbol_results = code_syms + test_syms
        missing_symbols = code_missing_syms + test_missing_syms
        missing_lines = code_missing_lines + test_missing_lines
        total_symbols += len(symbol_results)
        total_symbols_found += sum(1 for s in symbol_results if s["found"])
        ok = (
            code
            and tests
            and not missing_code
            and not missing_tests
            and not missing_symbols
            and not missing_lines
        )
        status = "PASS" if ok else "FAIL"
        row = {
            "id": req["id"],
            "name": req["name"],
            "status": status,
            "code": code,
            "tests": tests,
            "missing_code": missing_code,
            "missing_tests": missing_tests,
            "symbol_refs": symbol_results,
            "missing_symbols": missing_symbols,
            "missing_lines": missing_lines,
        }
        rows.append(row)
        if status != "PASS":
            failures.append(row)

    orphan_mappings = sorted(set(mapping) - {r["id"] for r in reqs})
    out = {
        "generated_at": datetime.now(timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ"),
        "requirements_source": os.path.relpath(args.requirements, root),
        "mapping_source": os.path.relpath(args.map, root),
        "summary": {
            "requirements": len(reqs),
            "passed": sum(1 for r in rows if r["status"] == "PASS"),
            "failed": len(failures),
            "symbol_refs": total_symbols,
            "symbols_found": total_symbols_found,
            "symbols_missing": total_symbols - total_symbols_found,
            "orphan_mappings": orphan_mappings,
        },
        "matrix": rows,
    }
    os.makedirs(os.path.dirname(args.out), exist_ok=True)
    with open(args.out, "w", encoding="utf-8") as f:
        json.dump(out, f, indent=2, ensure_ascii=False)
        f.write("\n")

    if failures:
        for row in failures:
            print(
                f"TRACEABILITY_FAIL {row['id']} code={len(row['code'])} tests={len(row['tests'])} "
                f"missing_code={len(row['missing_code'])} missing_tests={len(row['missing_tests'])} "
                f"missing_symbols={len(row['missing_symbols'])} missing_lines={len(row['missing_lines'])}",
                file=sys.stderr,
            )
    if orphan_mappings:
        print(f"TRACEABILITY_WARN orphan_mappings={','.join(orphan_mappings)}", file=sys.stderr)
    print(
        f"TRACEABILITY_MATRIX requirements={len(reqs)} pass={out['summary']['passed']} "
        f"fail={len(failures)} symbols={total_symbols_found}/{total_symbols} out={args.out}"
    )
    if args.gate and failures:
        return 1
    return 0


if __name__ == "__main__":
    raise SystemExit(main())