# Flask 应用工厂

from flask import Flask
from app.models import db
import os
import pathlib


def create_app():
    app = Flask(__name__)

    # 使用 run.py 的目录作为项目根目录（绝对路径，不依赖工作目录）
    import sys
    if hasattr(sys, '_MEIPASS'):
        BASE_DIR = pathlib.Path(sys._MEIPASS)
    else:
        BASE_DIR = pathlib.Path(__file__).resolve().parent.parent

    # 存储到 app.config，各处引用，不再各自计算
    app.config["BASE_DIR"] = BASE_DIR
    app.config["SECRET_KEY"] = "piano-practice-plan-secret-key-2026"
    app.config["DEBUG"] = True
    app.config["SQLALCHEMY_DATABASE_URI"] = (
        f"sqlite:///{BASE_DIR / 'data' / 'piano_plans.db'}"
    )
    app.config["SQLALCHEMY_TRACK_MODIFICATIONS"] = False

    app.config["PDF_OUTPUT_DIR"] = BASE_DIR / "output"
    app.config["API_CONFIG_FILE"] = BASE_DIR / "config" / "api_config.json"

    # 初始化数据库
    db.init_app(app)

    # 注册蓝图
    from app.routes import main_bp
    from app.routes.templates import templates_bp

    app.register_blueprint(main_bp)
    app.register_blueprint(templates_bp)

    # 创建数据库和目录
    with app.app_context():
        os.makedirs(os.path.join(BASE_DIR, "data"), exist_ok=True)
        os.makedirs(app.config["PDF_OUTPUT_DIR"], exist_ok=True)
        db.create_all()

        # 简单迁移：为已存在的数据库添加新字段（必须在init_default_templates之前）
        try:
            from sqlalchemy import text

            # 检查practice_time字段是否存在
            result = db.session.execute(text("PRAGMA table_info(students)"))
            columns = [row[1] for row in result]
            if "practice_time" not in columns:
                db.session.execute(
                    text(
                        "ALTER TABLE students ADD COLUMN practice_time VARCHAR(20) DEFAULT '30-60分钟'"
                    )
                )
                db.session.commit()
            if "wechat_nickname" not in columns:
                db.session.execute(
                    text("ALTER TABLE students ADD COLUMN wechat_nickname VARCHAR(100)")
                )
                db.session.commit()

            # 检查student_problems表的level字段
            result2 = db.session.execute(text("PRAGMA table_info(student_problems)"))
            columns2 = [row[1] for row in result2]
            if "level" not in columns2:
                db.session.execute(
                    text("ALTER TABLE student_problems ADD COLUMN level VARCHAR(20)")
                )
                db.session.commit()

            # 检查users表是否存在
            result3 = db.session.execute(
                text(
                    "SELECT name FROM sqlite_master WHERE type='table' AND name='users'"
                )
            )
            if not result3.fetchone():
                db.session.execute(
                    text(
                        """
                    CREATE TABLE users (
                        id INTEGER PRIMARY KEY,
                        username VARCHAR(50) UNIQUE NOT NULL,
                        password_hash VARCHAR(200) NOT NULL,
                        role VARCHAR(20) DEFAULT 'user',
                        created_at TIMESTAMP
                    )
                    """
                    )
                )
                db.session.commit()

            # 检查templates表是否有sort_order字段
            result4 = db.session.execute(text("PRAGMA table_info(templates)"))
            template_columns = [row[1] for row in result4]
            if "sort_order" not in template_columns:
                db.session.execute(text("ALTER TABLE templates ADD COLUMN sort_order INTEGER DEFAULT 0"))
                db.session.commit()

            # 检查practice_plans表是否有template_id字段
            result5 = db.session.execute(text("PRAGMA table_info(practice_plans)"))
            plan_columns = [row[1] for row in result5]
            if "template_id" not in plan_columns:
                db.session.execute(text("ALTER TABLE practice_plans ADD COLUMN template_id INTEGER REFERENCES templates(id)"))
                db.session.commit()

            # 检查practice_plans表是否有is_typical字段
            result6 = db.session.execute(text("PRAGMA table_info(practice_plans)"))
            plan_columns2 = [row[1] for row in result6]
            if "is_typical" not in plan_columns2:
                db.session.execute(text("ALTER TABLE practice_plans ADD COLUMN is_typical INTEGER DEFAULT 0"))
                db.session.commit()
        except Exception as e:
            print(f"数据库迁移: {e}")

        # 初始化默认模板（必须在迁移之后）
        # 已禁用：如果需要默认模板，请手动创建
        # from app.routes.templates import init_default_templates
        # init_default_templates()

    return app