#!/usr/bin/env python3
from __future__ import annotations

import argparse
import json
import os
import re
from datetime import datetime, timezone
from pathlib import Path
from typing import Any
from urllib.request import Request, urlopen

API_BASE = "https://forge.alexanderwhitestone.com/api/v1"
ORG = "Timmy_Foundation"
DEFAULT_TOKEN_PATH = os.path.expanduser("~/.config/gitea/token")
DEFAULT_OUTPUT = "reports/2026-04-17-the-door-fleet-work-orders-audit.md"


def extract_issue_numbers(body: str) -> list[int]:
    numbers: list[int] = []
    seen: set[int] = set()
    for match in re.finditer(r"#(\d+)", body or ""):
        value = int(match.group(1))
        if value in seen:
            continue
        seen.add(value)
        numbers.append(value)
    return numbers


def api_get(repo: str, path: str, token: str) -> Any:
    req = Request(
        f"{API_BASE}/repos/{ORG}/{repo}{path}",
        headers={"Authorization": f"token {token}"},
    )
    with urlopen(req, timeout=30) as resp:
        return json.loads(resp.read().decode())


def fetch_open_prs(repo: str, token: str) -> list[dict[str, Any]]:
    prs: list[dict[str, Any]] = []
    page = 1
    while True:
        batch = api_get(repo, f"/pulls?state=open&limit=100&page={page}", token)
        if not batch:
            break
        prs.extend(batch)
        page += 1
    return prs


def fetch_live_open_issue_count(repo: str, token: str) -> int:
    total = 0
    page = 1
    while True:
        batch = api_get(repo, f"/issues?state=open&limit=100&page={page}", token)
        if not batch:
            break
        total += sum(1 for item in batch if not item.get("pull_request"))
        page += 1
    return total


def parse_claimed_summary(body: str) -> tuple[int | None, int | None]:
    issue_match = re.search(r"has\s+(\d+)\s+real issues", body or "", flags=re.IGNORECASE)
    pr_match = re.search(r"and\s+(\d+)\s+open PRs", body or "", flags=re.IGNORECASE)
    claimed_open_issues = int(issue_match.group(1)) if issue_match else None
    claimed_open_prs = int(pr_match.group(1)) if pr_match else None
    return claimed_open_issues, claimed_open_prs


def summarize_open_pr_coverage(issue_num: int, open_prs: list[dict[str, Any]]) -> str:
    matches: list[str] = []
    seen: set[int] = set()
    for pr in open_prs:
        pr_num = pr["number"]
        if pr_num in seen:
            continue
        text = "\n".join(
            [
                pr.get("title") or "",
                pr.get("body") or "",
                (pr.get("head") or {}).get("ref") or "",
            ]
        )
        if f"#{issue_num}" not in text:
            continue
        seen.add(pr_num)
        matches.append(f"open PR #{pr_num}")
    return ", ".join(matches) if matches else "none"


def classify_issue_reference(ref_issue: dict[str, Any], open_prs: list[dict[str, Any]]) -> dict[str, Any]:
    issue_num = ref_issue["number"]
    state = ref_issue.get("state") or "unknown"
    coverage = summarize_open_pr_coverage(issue_num, open_prs)
    if state == "closed":
        classification = "closed_issue"
    elif coverage != "none":
        classification = "open_with_current_pr"
    else:
        classification = "open_no_current_pr"
    return {
        "number": issue_num,
        "state": state,
        "classification": classification,
        "title": ref_issue.get("title") or "",
        "current_pr_coverage": coverage,
        "url": ref_issue.get("html_url") or ref_issue.get("url") or "",
    }


def classify_pr_reference(repo: str, pr_num: int, token: str) -> dict[str, Any]:
    pr = api_get(repo, f"/pulls/{pr_num}", token)
    state = pr.get("state") or "unknown"
    merged = bool(pr.get("merged"))
    if merged:
        classification = "merged_pr"
    elif state == "open":
        classification = "open_pr"
    else:
        classification = "closed_unmerged_pr"
    return {
        "number": pr_num,
        "state": state,
        "merged": merged,
        "classification": classification,
        "title": pr.get("title") or "",
        "head": (pr.get("head") or {}).get("ref") or "",
        "url": pr.get("html_url") or pr.get("url") or "",
    }


def table(rows: list[dict[str, Any]], columns: list[tuple[str, str]]) -> str:
    headers = [title for title, _ in columns]
    keys = [key for _, key in columns]
    if not rows:
        return "| None |\n|---|\n| None |"
    lines = ["| " + " | ".join(headers) + " |", "|" + "|".join(["---"] * len(headers)) + "|"]
    for row in rows:
        values: list[str] = []
        for key in keys:
            value = row.get(key, "")
            if key == "number" and value != "":
                value = f"#{value}"
            values.append(str(value).replace("\n", " "))
        lines.append("| " + " | ".join(values) + " |")
    return "\n".join(lines)


def render_report(
    *,
    source_issue: int,
    source_title: str,
    generated_at: str,
    claimed_open_issues: int | None,
    claimed_open_prs: int | None,
    live_open_issues: int,
    live_open_prs: int,
    issue_rows: list[dict[str, Any]],
    pr_rows: list[dict[str, Any]],
) -> str:
    open_with_current_pr = [row for row in issue_rows if row["classification"] == "open_with_current_pr"]
    open_no_current_pr = [row for row in issue_rows if row["classification"] == "open_no_current_pr"]
    closed_issues = [row for row in issue_rows if row["classification"] == "closed_issue"]
    merged_prs = [row for row in pr_rows if row["classification"] == "merged_pr"]
    open_pr_refs = [row for row in pr_rows if row["classification"] == "open_pr"]
    closed_unmerged_prs = [row for row in pr_rows if row["classification"] == "closed_unmerged_pr"]

    drift_lines = [
        f"- The issue body claimed {claimed_open_issues if claimed_open_issues is not None else 'unknown'} real issues and {claimed_open_prs if claimed_open_prs is not None else 'unknown'} open PRs.",
        f"- Live repo state now shows {live_open_issues} open issues and {live_open_prs} open PRs.",
        f"- Referenced issues now break down into {len(closed_issues)} closed, {len(open_with_current_pr)} open_with_current_pr, and {len(open_no_current_pr)} open_no_current_pr.",
        f"- Referenced PRs now break down into {len(merged_prs)} merged_pr, {len(open_pr_refs)} open_pr, and {len(closed_unmerged_prs)} closed_unmerged_pr.",
    ]

    return "\n".join(
        [
            f"# The Door Fleet Work Orders Audit — issue #{source_issue}",
            "",
            f"Generated: {generated_at}",
            f"Source issue: `{source_title}`",
            "",
            "## Source Snapshot",
            "",
            "Issue #75 is a dated triage work-order sheet, not a normal feature request. The durable deliverable is a truth-restored audit of the referenced issue and PR set against live forge state.",
            "",
            "## Live Summary",
            "",
            f"- Referenced issues audited: {len(issue_rows)}",
            f"- Referenced PRs audited: {len(pr_rows)}",
            f"- Live repo open issues: {live_open_issues}",
            f"- Live repo open PRs: {live_open_prs}",
            f"- Open referenced issues with current PR coverage: {len(open_with_current_pr)}",
            f"- Open referenced issues with no current PR coverage: {len(open_no_current_pr)}",
            f"- Closed referenced issues: {len(closed_issues)}",
            f"- Closed-unmerged referenced PRs: {len(closed_unmerged_prs)}",
            "",
            "## Issue Body Drift",
            "",
            *drift_lines,
            "",
            "## Referenced Issue Snapshot",
            "",
            table(
                issue_rows,
                [
                    ("Issue", "number"),
                    ("State", "state"),
                    ("Classification", "classification"),
                    ("Current PR Coverage", "current_pr_coverage"),
                    ("Title", "title"),
                ],
            ),
            "",
            "## Referenced PR Snapshot",
            "",
            table(
                pr_rows,
                [
                    ("PR", "number"),
                    ("State", "state"),
                    ("Merged", "merged"),
                    ("Classification", "classification"),
                    ("Head", "head"),
                    ("Title", "title"),
                ],
            ),
            "",
            "## Recommended Next Actions",
            "",
            "1. Do not trust the original work-order body as live truth; use this audit artifact for current planning.",
            "2. Re-triage the open_no_current_pr issues individually before dispatching new work, because the old PR references are now stale.",
            "3. Treat closed_unmerged_pr references as historical attempts, not active review lanes.",
            "4. If future work orders are needed, generate them from live forge state instead of reusing the 2026-04-09 issue body.",
            "5. This audit preserves operator memory; it does not claim all referenced work orders are complete.",
        ]
    ) + "\n"


def build_audit(repo: str, issue_number: int, token: str) -> tuple[dict[str, Any], list[dict[str, Any]], list[dict[str, Any]]]:
    source_issue = api_get(repo, f"/issues/{issue_number}", token)
    body = source_issue.get("body") or ""
    refs = extract_issue_numbers(body)
    open_prs = fetch_open_prs(repo, token)
    claimed_open_issues, claimed_open_prs = parse_claimed_summary(body)
    issue_rows: list[dict[str, Any]] = []
    pr_rows: list[dict[str, Any]] = []
    for ref in refs:
        issue_like = api_get(repo, f"/issues/{ref}", token)
        if issue_like.get("pull_request"):
            pr_rows.append(classify_pr_reference(repo, ref, token))
        else:
            issue_rows.append(classify_issue_reference(issue_like, open_prs))
    metadata = {
        "source_title": source_issue.get("title") or "",
        "claimed_open_issues": claimed_open_issues,
        "claimed_open_prs": claimed_open_prs,
        "live_open_issues": fetch_live_open_issue_count(repo, token),
        "live_open_prs": len(open_prs),
    }
    return metadata, issue_rows, pr_rows


def main() -> int:
    parser = argparse.ArgumentParser(description="Audit The Door fleet work orders issue against live forge state.")
    parser.add_argument("--repo", default="the-door")
    parser.add_argument("--issue", type=int, default=75)
    parser.add_argument("--token-file", default=DEFAULT_TOKEN_PATH)
    parser.add_argument("--output", default=DEFAULT_OUTPUT)
    args = parser.parse_args()

    token = Path(args.token_file).read_text(encoding="utf-8").strip()
    generated_at = datetime.now(timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ")
    metadata, issue_rows, pr_rows = build_audit(args.repo, args.issue, token)
    report = render_report(
        source_issue=args.issue,
        source_title=metadata["source_title"],
        generated_at=generated_at,
        claimed_open_issues=metadata["claimed_open_issues"],
        claimed_open_prs=metadata["claimed_open_prs"],
        live_open_issues=metadata["live_open_issues"],
        live_open_prs=metadata["live_open_prs"],
        issue_rows=issue_rows,
        pr_rows=pr_rows,
    )
    output_path = Path(args.output)
    output_path.parent.mkdir(parents=True, exist_ok=True)
    output_path.write_text(report, encoding="utf-8")
    print(output_path)
    return 0


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