#!/usr/bin/env python3
import argparse
import json
import os
import re
import sys
import urllib.request
from pathlib import Path

API_BASE = "https://forge.alexanderwhitestone.com/api/v1"
LOW_RISK_PREFIXES = (
    'docs/', 'reports/', 'notes/', 'tickets/', 'research/', 'briefings/',
    'twitter-archive/notes/', 'tests/'
)
LOW_RISK_SUFFIXES = {'.md', '.txt', '.jsonl'}
MEDIUM_RISK_PREFIXES = ('.gitea/workflows/',)
HIGH_RISK_PREFIXES = (
    'scripts/', 'deploy/', 'infrastructure/', 'metrics/', 'heartbeat/',
    'wizards/', 'evennia/', 'uniwizard/', 'uni-wizard/', 'timmy-local/',
    'evolution/'
)
HIGH_RISK_SUFFIXES = {'.py', '.sh', '.ini', '.service'}


def read_changed_files(path):
    return [line.strip() for line in Path(path).read_text(encoding='utf-8').splitlines() if line.strip()]


def classify_risk(files):
    if not files:
        return 'high'
    level = 'low'
    for file_path in files:
        path = file_path.strip()
        suffix = Path(path).suffix.lower()
        if path.startswith(LOW_RISK_PREFIXES):
            continue
        if path.startswith(HIGH_RISK_PREFIXES) or suffix in HIGH_RISK_SUFFIXES:
            return 'high'
        if path.startswith(MEDIUM_RISK_PREFIXES):
            level = 'medium'
            continue
        if path.startswith(LOW_RISK_PREFIXES) or suffix in LOW_RISK_SUFFIXES:
            continue
        level = 'high'
    return level


def validate_pr_body(title, body):
    details = []
    combined = f"{title}\n{body}".strip()
    if not re.search(r'#\d+', combined):
        details.append('PR body/title must include an issue reference like #562.')
    if not re.search(r'(^|\n)\s*(verification|tests?)\s*:', body, re.IGNORECASE):
        details.append('PR body must include a Verification: section.')
    return (len(details) == 0, details)


def build_comment_body(syntax_status, tests_status, criteria_status, risk_level):
    statuses = {
        'syntax': syntax_status,
        'tests': tests_status,
        'criteria': criteria_status,
    }
    all_clean = all(value == 'success' for value in statuses.values())
    action = 'auto-merge' if all_clean and risk_level == 'low' else 'human review'
    lines = [
        '## Agent PR Gate',
        '',
        '| Check | Status |',
        '|-------|--------|',
        f"| Syntax / parse | {syntax_status} |",
        f"| Test suite | {tests_status} |",
        f"| PR criteria | {criteria_status} |",
        f"| Risk level | {risk_level} |",
        '',
    ]
    failed = [name for name, value in statuses.items() if value != 'success']
    if failed:
        lines.append('### Failure details')
        for name in failed:
            lines.append(f'- {name} reported failure. Inspect the workflow logs for that step.')
    else:
        lines.append('All automated checks passed.')
    lines.extend([
        '',
        f'Recommendation: {action}.',
        'Low-risk documentation/test-only PRs may be auto-merged. Operational changes stay in human review.',
    ])
    return '\n'.join(lines)


def _read_event(event_path):
    data = json.loads(Path(event_path).read_text(encoding='utf-8'))
    pr = data.get('pull_request') or {}
    repo = (data.get('repository') or {}).get('full_name') or os.environ.get('GITHUB_REPOSITORY')
    pr_number = pr.get('number') or data.get('number')
    title = pr.get('title') or ''
    body = pr.get('body') or ''
    return repo, pr_number, title, body


def _request_json(method, url, token, payload=None):
    data = None if payload is None else json.dumps(payload).encode('utf-8')
    headers = {'Authorization': f'token {token}', 'Content-Type': 'application/json'}
    req = urllib.request.Request(url, data=data, headers=headers, method=method)
    with urllib.request.urlopen(req, timeout=30) as resp:
        return json.loads(resp.read().decode('utf-8'))


def post_comment(repo, pr_number, token, body):
    url = f'{API_BASE}/repos/{repo}/issues/{pr_number}/comments'
    return _request_json('POST', url, token, {'body': body})


def merge_pr(repo, pr_number, token):
    url = f'{API_BASE}/repos/{repo}/pulls/{pr_number}/merge'
    return _request_json('POST', url, token, {'Do': 'merge'})


def cmd_classify_risk(args):
    files = list(args.files or [])
    if args.files_file:
        files.extend(read_changed_files(args.files_file))
    print(json.dumps({'risk': classify_risk(files), 'files': files}, indent=2))
    return 0


def cmd_validate_pr(args):
    _, _, title, body = _read_event(args.event_path)
    ok, details = validate_pr_body(title, body)
    if ok:
        print('PR body validation passed.')
        return 0
    for detail in details:
        print(detail)
    return 1


def cmd_comment(args):
    repo, pr_number, _, _ = _read_event(args.event_path)
    body = build_comment_body(args.syntax, args.tests, args.criteria, args.risk)
    post_comment(repo, pr_number, args.token, body)
    print(f'Commented on PR #{pr_number} in {repo}.')
    return 0


def cmd_merge(args):
    repo, pr_number, _, _ = _read_event(args.event_path)
    merge_pr(repo, pr_number, args.token)
    print(f'Merged PR #{pr_number} in {repo}.')
    return 0


def build_parser():
    parser = argparse.ArgumentParser(description='Agent PR CI helpers for timmy-home.')
    sub = parser.add_subparsers(dest='command', required=True)

    classify = sub.add_parser('classify-risk')
    classify.add_argument('--files-file')
    classify.add_argument('files', nargs='*')
    classify.set_defaults(func=cmd_classify_risk)

    validate = sub.add_parser('validate-pr')
    validate.add_argument('--event-path', required=True)
    validate.set_defaults(func=cmd_validate_pr)

    comment = sub.add_parser('comment')
    comment.add_argument('--event-path', required=True)
    comment.add_argument('--token', required=True)
    comment.add_argument('--syntax', required=True)
    comment.add_argument('--tests', required=True)
    comment.add_argument('--criteria', required=True)
    comment.add_argument('--risk', required=True)
    comment.set_defaults(func=cmd_comment)

    merge = sub.add_parser('merge')
    merge.add_argument('--event-path', required=True)
    merge.add_argument('--token', required=True)
    merge.set_defaults(func=cmd_merge)
    return parser


def main(argv=None):
    parser = build_parser()
    args = parser.parse_args(argv)
    return args.func(args)


if __name__ == '__main__':
    sys.exit(main())