# -*- coding: utf-8 -*-
"""ziwei-power SQLite 数据库操作层"""

import sqlite3
import json
import os
from datetime import datetime

DB_DIR = os.path.join(os.path.expanduser('~'), '.workbuddy', 'data', 'ziwei-power')
os.makedirs(DB_DIR, exist_ok=True)
DB_PATH = os.path.join(DB_DIR, 'ziwei_power.db')

# 当前数据库 schema 版本 —— 改表结构时必须 +1 并补迁移逻辑
CURRENT_SCHEMA_VERSION = 1


def get_conn():
    conn = sqlite3.connect(DB_PATH)
    conn.row_factory = sqlite3.Row
    return conn


def _get_schema_version(conn):
    """读取当前数据库的 schema 版本，无表时返回 0"""
    conn.execute('''
        CREATE TABLE IF NOT EXISTS schema_version (
            version INTEGER NOT NULL
        )
    ''')
    row = conn.execute('SELECT version FROM schema_version').fetchone()
    return row['version'] if row else 0


def _set_schema_version(conn, version):
    """写入 schema 版本"""
    conn.execute('DELETE FROM schema_version')
    conn.execute('INSERT INTO schema_version (version) VALUES (?)', (version,))


def init_db():
    """初始化数据库表 & 自动迁移"""
    conn = get_conn()
    current = _get_schema_version(conn)

    # ── 迁移步骤（按版本号递增）────────────────────────
    if current < 1:
        # v1: 初始表结构
        conn.execute('''
            CREATE TABLE IF NOT EXISTS checkins (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                date TEXT UNIQUE NOT NULL,
                data TEXT NOT NULL,
                created_at TEXT NOT NULL,
                updated_at TEXT NOT NULL
            )
        ''')

    # ── 将来加字段/改表在此扩展 ──
    # if current < 2:
    #     conn.execute('ALTER TABLE checkins ADD COLUMN tags TEXT DEFAULT ""')
    #     # 可选：对已有行做数据补全
    #     conn.execute("UPDATE checkins SET tags = '[]' WHERE tags IS NULL")

    # ── 写入最新版本号 ──
    _set_schema_version(conn, CURRENT_SCHEMA_VERSION)
    conn.commit()
    conn.close()


def get_checkin(date_str):
    """获取某天的打卡记录，返回 dict 或 None"""
    conn = get_conn()
    row = conn.execute('SELECT * FROM checkins WHERE date = ?', (date_str,)).fetchone()
    conn.close()
    if row:
        return {
            'id': row['id'],
            'date': row['date'],
            'data': json.loads(row['data']),
            'created_at': row['created_at'],
            'updated_at': row['updated_at']
        }
    return None


def save_checkin(date_str, data_dict):
    """保存或更新打卡记录"""
    now = datetime.now().isoformat()
    conn = get_conn()
    existing = conn.execute('SELECT id FROM checkins WHERE date = ?', (date_str,)).fetchone()
    json_data = json.dumps(data_dict, ensure_ascii=False)
    if existing:
        conn.execute(
            'UPDATE checkins SET data = ?, updated_at = ? WHERE date = ?',
            (json_data, now, date_str)
        )
    else:
        conn.execute(
            'INSERT INTO checkins (date, data, created_at, updated_at) VALUES (?, ?, ?, ?)',
            (date_str, json_data, now, now)
        )
    conn.commit()
    conn.close()


def delete_checkin(date_str):
    """删除某天的打卡记录"""
    conn = get_conn()
    conn.execute('DELETE FROM checkins WHERE date = ?', (date_str,))
    conn.commit()
    conn.close()


def get_all_checkins():
    """获取所有打卡记录，按日期倒序"""
    conn = get_conn()
    rows = conn.execute('SELECT * FROM checkins ORDER BY date DESC').fetchall()
    conn.close()
    results = []
    for row in rows:
        results.append({
            'id': row['id'],
            'date': row['date'],
            'data': json.loads(row['data']),
            'created_at': row['created_at'],
            'updated_at': row['updated_at']
        })
    return results