#!/usr/bin/env python3
"""
Create one Gitea issue from one email (by UID), then mark the email as read.
If --title and/or --body are provided (formalized by agent), use them; else use subject and body from the email.
Usage: ./gitea-issues/mail-create-issue-from-email.sh --uid <uid> [--title "..." ] [--body "..." ]
"""

from __future__ import annotations

import argparse
import email
import imaplib
import ssl
import sys
from email.header import decode_header
from pathlib import Path

sys.path.insert(0, str(Path(__file__).resolve().parent))
from mail_common import (
    create_gitea_issue,
    load_gitea_config,
    load_imap_config,
    repo_root,
    sanitize_title,
)


def decode_header_value(header: str | None) -> str:
    if not header:
        return ""
    from email.header import decode_header as dh
    parts = dh(header)
    result = []
    for part, charset in parts:
        if isinstance(part, bytes):
            result.append(part.decode(charset or "utf-8", errors="replace"))
        else:
            result.append(part)
    return "".join(result)


def get_text_body(msg: email.message.Message) -> str:
    if msg.is_multipart():
        for part in msg.walk():
            if part.get_content_type() == "text/plain":
                payload = part.get_payload(decode=True)
                if payload:
                    return payload.decode(part.get_content_charset() or "utf-8", errors="replace")
        return ""
    payload = msg.get_payload(decode=True)
    if not payload:
        return ""
    return payload.decode(msg.get_content_charset() or "utf-8", errors="replace")


def main() -> None:
    ap = argparse.ArgumentParser(description="Create one Gitea issue from one email by UID")
    ap.add_argument("--uid", required=True, help="IMAP message UID")
    ap.add_argument("--title", default="", help="Formalized issue title (else use subject)")
    ap.add_argument("--body", default="", help="Formalized issue body (else use email body + From)")
    args = ap.parse_args()

    cfg = load_imap_config()
    if not cfg["user"] or not cfg["password"]:
        root = repo_root()
        env_path = root / ".secrets" / "gitea-issues" / "imap-bridge.env"
        print("[gitea-issues] ERROR: IMAP_USER and IMAP_PASSWORD required.", file=sys.stderr)
        sys.exit(1)

    gitea = load_gitea_config()
    if not gitea["token"]:
        print("[gitea-issues] ERROR: GITEA_TOKEN not set.", file=sys.stderr)
        sys.exit(1)

    mail = imaplib.IMAP4(cfg["host"], int(cfg["port"]))
    if cfg["use_starttls"]:
        mail.starttls(ssl.create_default_context())
    mail.login(cfg["user"], cfg["password"])
    mail.select("INBOX")
    _, data = mail.fetch(args.uid, "(RFC822)")
    if not data or not data[0]:
        print("[gitea-issues] ERROR: Message UID not found.", file=sys.stderr)
        mail.logout()
        sys.exit(1)

    msg = email.message_from_bytes(data[0][1])
    from_ = decode_header_value(msg.get("From"))
    subject = decode_header_value(msg.get("Subject"))
    body_text = get_text_body(msg)
    body_for_issue = f"**From:** {from_}\n\n{body_text}".strip()

    title = args.title.strip() if args.title else sanitize_title(subject)
    body = args.body.strip() if args.body else body_for_issue

    issue = create_gitea_issue(title, body)
    if not issue:
        print("[gitea-issues] ERROR: Failed to create issue.", file=sys.stderr)
        mail.logout()
        sys.exit(1)

    mail.store(args.uid, "+FLAGS", "\\Seen")
    mail.logout()

    num = issue.get("number", "?")
    print(f"[gitea-issues] Created issue #{num}: {title[:60]}")
    print(f"ISSUE_NUMBER={num}")


if __name__ == "__main__":
    main()