from __future__ import annotations

import argparse
import hashlib
import json
from pathlib import Path
from typing import Any


REPOSITORY_ROOT = Path(__file__).resolve().parents[1]
DEFAULT_MANIFEST = (
    REPOSITORY_ROOT / "artifacts" / "evidence" / "accuracy" / "P1" / "evidence-manifest.json"
)
REQUIRED_DOCUMENTS = tuple(
    REPOSITORY_ROOT / "docs" / "accuracy-program" / f"{index:02d}-{name}.md"
    for index, name in (
        (0, "execution-contract"),
        (1, "system-inventory"),
        (2, "data-lineage"),
        (3, "baseline-and-gaps"),
        (4, "risk-register"),
        (5, "metric-framework"),
        (6, "implementation-roadmap"),
    )
)


def sha256_file(path: Path) -> str:
    digest = hashlib.sha256()
    with path.open("rb") as handle:
        for chunk in iter(lambda: handle.read(1024 * 1024), b""):
            digest.update(chunk)
    return digest.hexdigest()


def verify_record(item: dict[str, Any]) -> list[str]:
    errors: list[str] = []
    relative = item.get("path")
    if not isinstance(relative, str):
        return ["manifest record has no string path"]
    path = REPOSITORY_ROOT / relative
    if not path.is_file():
        return [f"missing file: {relative}"]
    expected_size = item.get("size_bytes")
    if path.stat().st_size != expected_size:
        errors.append(
            f"size mismatch for {relative}: expected {expected_size}, got {path.stat().st_size}"
        )
    expected_hash = item.get("sha256")
    actual_hash = sha256_file(path)
    if actual_hash != expected_hash:
        errors.append(
            f"sha256 mismatch for {relative}: expected {expected_hash}, got {actual_hash}"
        )
    return errors


def main() -> int:
    parser = argparse.ArgumentParser(description="Verify GeoIntel Accuracy P1 evidence and program hashes.")
    parser.add_argument("--manifest", type=Path, default=DEFAULT_MANIFEST)
    args = parser.parse_args()
    manifest_path = args.manifest.expanduser().resolve()
    if not manifest_path.is_file():
        parser.error(f"evidence manifest does not exist: {manifest_path}")

    payload = json.loads(manifest_path.read_text(encoding="utf-8"))
    errors: list[str] = []
    evidence_records = payload.get("evidence_files")
    program_records = payload.get("program_files")
    if not isinstance(evidence_records, list) or not isinstance(program_records, list):
        errors.append("manifest must contain evidence_files and program_files arrays")
        evidence_records = []
        program_records = []

    for item in [*evidence_records, *program_records]:
        if not isinstance(item, dict):
            errors.append("manifest file record is not an object")
            continue
        errors.extend(verify_record(item))

    evidence_root = REPOSITORY_ROOT / str(payload.get("evidence_root") or "")
    listed = {
        str(item.get("path"))
        for item in evidence_records
        if isinstance(item, dict) and isinstance(item.get("path"), str)
    }
    current = {
        path.relative_to(REPOSITORY_ROOT).as_posix()
        for path in evidence_root.rglob("*")
        if path.is_file() and path.resolve() != manifest_path
    }
    for relative in sorted(current - listed):
        errors.append(f"unlisted evidence file: {relative}")
    for relative in sorted(listed - current):
        errors.append(f"listed evidence file no longer exists: {relative}")

    for document in REQUIRED_DOCUMENTS:
        if not document.is_file() or document.stat().st_size == 0:
            errors.append(f"required document missing or empty: {document.relative_to(REPOSITORY_ROOT)}")

    status_path = REPOSITORY_ROOT / "docs" / "accuracy-program" / "status.json"
    if not status_path.is_file():
        errors.append("required status.json is missing")
    else:
        status = json.loads(status_path.read_text(encoding="utf-8"))
        if status.get("phase1", {}).get("status") != "complete":
            errors.append("status.json must mark Phase 1 complete")
        if status.get("release", {}).get("status") != "blocked":
            errors.append("status.json must keep release blocked")
        if status.get("release", {}).get("promotion_allowed") is not False:
            errors.append("status.json must keep promotion disallowed")
        if status.get("scope", {}).get("national_building_validation") is not False:
            errors.append("status.json must not claim national building validation")

    summary = {
        "schema_version": 1,
        "status": "passed" if not errors else "failed",
        "manifest": manifest_path.relative_to(REPOSITORY_ROOT).as_posix(),
        "evidence_files_checked": len(evidence_records),
        "program_files_checked": len(program_records),
        "errors": errors,
    }
    print(json.dumps(summary, indent=2, sort_keys=True))
    return 0 if not errors else 1


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