#!/usr/bin/env python3
# /// script
# requires-python = ">=3.11"
# dependencies = ["pyyaml"]
# ///
"""Migrate reminders from reminder.yaml to SQLite.

Reads reminder.yaml, inserts into reminders.sqlite, then renames YAML to .bak.
"""

from __future__ import annotations

import sys
from datetime import datetime, timezone
from os import environ
from pathlib import Path

# db.py lives in skills/remind/scripts/
SCRIPTS_DIR = Path(__file__).resolve().parent.parent / "skills" / "remind" / "scripts"
sys.path.insert(0, str(SCRIPTS_DIR))

import yaml
from db import get_db, init_db

WORKSPACE = Path(__file__).resolve().parent.parent
YAML_PATH = WORKSPACE / "reminder.yaml"
DEFAULT_DB_PATH = WORKSPACE / "db" / "reminders.sqlite"
DB_PATH = Path(environ.get("REMIND_DB", str(DEFAULT_DB_PATH)))


def _now() -> str:
    return datetime.now(timezone.utc).isoformat(timespec="seconds")


def _parse_window(window: str) -> tuple[int, int]:
    start_str, end_str = window.split("-", 1)
    start = _hhmm_to_minutes(start_str.strip())
    end = _hhmm_to_minutes(end_str.strip())
    return start, end


def _hhmm_to_minutes(value: str) -> int:
    h, m = value.split(":")
    return int(h) * 60 + int(m)


def main() -> int:
    if not YAML_PATH.exists():
        print("No reminder.yaml found — nothing to migrate.")
        return 0

    data = yaml.safe_load(YAML_PATH.read_text(encoding="utf-8")) or {}
    reminders = data.get("reminders", [])
    if not reminders:
        print("reminder.yaml is empty — nothing to migrate.")
        return 0

    init_db(DB_PATH)
    conn = get_db(DB_PATH)
    try:
        conn.execute("BEGIN")
        for item in reminders:
            text = (item.get("text") or "").strip()
            if not text:
                continue
            now = _now()
            cur = conn.execute(
                "INSERT INTO reminders (text, enabled, timezone, created_at, updated_at) VALUES (?, 1, 'Europe/Prague', ?, ?)",
                (text, now, now),
            )
            rid = cur.lastrowid

            at = item.get("at")
            at_times = item.get("at_times", [])
            if at:
                at_times = [at] + list(at_times)
            for at_str in at_times:
                conn.execute(
                    "INSERT INTO schedule_at (reminder_id, at_datetime) VALUES (?, ?)",
                    (rid, at_str),
                )

            for expr in item.get("cron_exprs", []):
                conn.execute(
                    "INSERT INTO schedule_cron (reminder_id, cron_expr) VALUES (?, ?)",
                    (rid, expr),
                )

            random_cfg = item.get("random")
            if random_cfg:
                start, end = _parse_window(random_cfg["window"])
                conn.execute(
                    """
                    INSERT INTO schedule_random
                        (reminder_id, times_per_day, window_start, window_end, days_filter, from_date, until_date)
                    VALUES (?, ?, ?, ?, ?, ?, ?)
                    """,
                    (
                        rid,
                        random_cfg["times_per_day"],
                        start,
                        end,
                        random_cfg.get("days"),
                        random_cfg.get("from"),
                        random_cfg.get("until"),
                    ),
                )

        conn.execute("COMMIT")
        backup = YAML_PATH.with_suffix(".yaml.bak")
        YAML_PATH.rename(backup)
        print(f"Migrated {len(reminders)} reminders to {DB_PATH}")
        print(f"Renamed {YAML_PATH} to {backup}")
        return 0
    except Exception as exc:
        conn.execute("ROLLBACK")
        print(f"Migration failed: {exc}", file=sys.stderr)
        return 1
    finally:
        conn.close()


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