from flask_sqlalchemy import SQLAlchemy
from flask_login import UserMixin
from datetime import datetime
from utils.timezone import taiwan_now
from werkzeug.security import generate_password_hash, check_password_hash

db = SQLAlchemy()

class User(db.Model, UserMixin):
    # 修改 table name
    __tablename__ = 'tst_user'
    id = db.Column(db.Integer, primary_key=True)
    username = db.Column(db.String(120), unique=True, nullable=False)
    password_hash = db.Column(db.String(255), nullable=False)
    name = db.Column(db.String(100), nullable=False)
    role = db.Column(db.Enum('viewer', 'editor', 'admin'), nullable=False, default='viewer')
    last_login = db.Column(db.DateTime)

    def set_password(self, password: str) -> None:
        self.password_hash = generate_password_hash(password)

    def check_password(self, password: str) -> bool:
        return check_password_hash(self.password_hash, password)

class TempSpec(db.Model):
    # 新增並設定 table name
    __tablename__ = 'tst_temp_spec'
    id = db.Column(db.Integer, primary_key=True)
    spec_code = db.Column(db.String(20), nullable=False)
    applicant = db.Column(db.String(50))
    title = db.Column(db.String(100))
    content = db.Column(db.Text)
    start_date = db.Column(db.Date)
    end_date = db.Column(db.Date)
    status = db.Column(db.Enum('pending_approval', 'active', 'expired', 'terminated'), nullable=False, default='pending_approval')
    created_at = db.Column(db.DateTime)
    extension_count = db.Column(db.Integer, default=0)
    termination_reason = db.Column(db.Text, nullable=True)
    notification_emails = db.Column(db.Text, nullable=True)  # 儲存通知郵件清單，以分號分隔

    # 關聯到 Upload 和 SpecHistory，並設定級聯刪除
    uploads = db.relationship('Upload', back_populates='spec', cascade='all, delete-orphan')
    history = db.relationship('SpecHistory', back_populates='spec', cascade='all, delete-orphan')

class Upload(db.Model):
    # 新增並設定 table name
    __tablename__ = 'tst_upload'
    id = db.Column(db.Integer, primary_key=True)
    # 注意：這裡的 ForeignKey 也要更新為新的 table name
    temp_spec_id = db.Column(db.Integer, db.ForeignKey('tst_temp_spec.id', ondelete='CASCADE'), nullable=False)
    filename = db.Column(db.String(200))
    upload_time = db.Column(db.DateTime)
    
    spec = db.relationship('TempSpec', back_populates='uploads')

class SpecHistory(db.Model):
    # 修改 table name
    __tablename__ = 'tst_spec_history'
    id = db.Column(db.Integer, primary_key=True)
    # 注意：這裡的 ForeignKey 也要更新為新的 table name
    spec_id = db.Column(db.Integer, db.ForeignKey('tst_temp_spec.id', ondelete='CASCADE'), nullable=False)
    user_id = db.Column(db.Integer, db.ForeignKey('tst_user.id', ondelete='SET NULL'), nullable=True)
    action = db.Column(db.String(50), nullable=False)
    details = db.Column(db.Text, nullable=True)
    timestamp = db.Column(db.DateTime, default=taiwan_now)

    # 建立與 User 和 TempSpec 的關聯，方便查詢
    user = db.relationship('User')
    spec = db.relationship('TempSpec', back_populates='history')