"""
郵件帳號 Model
支援員工在不同網域擁有多個郵件帳號,並管理配額
符合設計文件規範: HR Portal設計文件.md
"""
from datetime import datetime
from sqlalchemy import Column, Integer, String, Boolean, DateTime, Text, ForeignKey, Index
from sqlalchemy.orm import relationship

from app.db.base import Base


class EmailAccount(Base):
    """郵件帳號表 (一個員工可以有多個郵件帳號)"""

    __tablename__ = "tenant_email_accounts"
    __table_args__ = (
        # 郵件地址必須唯一
        Index("idx_email_accounts_email", "email_address", unique=True),
        # 員工索引
        Index("idx_email_accounts_employee", "employee_id"),
        # 租戶索引
        Index("idx_email_accounts_tenant", "tenant_id"),
        # 狀態索引 (快速查詢啟用的帳號)
        Index("idx_email_accounts_active", "is_active"),
    )

    id = Column(Integer, primary_key=True, index=True)
    tenant_id = Column(
        Integer,
        ForeignKey("tenants.id", ondelete="CASCADE"),
        nullable=False,
        index=True,
        comment="租戶 ID"
    )

    # 支援個人/部門信箱
    account_type = Column(
        String(20),
        default='personal',
        nullable=False,
        comment="帳號類型: personal(個人), department(部門)"
    )
    employee_id = Column(
        Integer,
        ForeignKey("tenant_employees.id", ondelete="CASCADE"),
        nullable=True,  # 部門信箱不需要 employee_id
        index=True,
        comment="員工 ID (僅 personal 類型需要)"
    )
    department_id = Column(
        Integer,
        ForeignKey("tenant_departments.id", ondelete="CASCADE"),
        nullable=True,
        index=True,
        comment="部門 ID (僅 department 類型需要)"
    )

    # 郵件設定
    email_address = Column(
        String(255),
        unique=True,
        nullable=False,
        index=True,
        comment="郵件地址 (例如: porsche.chen@lab.taipei)"
    )
    quota_mb = Column(
        Integer,
        default=2048,
        nullable=False,
        comment="配額 (MB),依職級: Junior=2048, Mid=3072, Senior=5120, Manager=10240"
    )

    # 進階功能
    forward_to = Column(
        String(255),
        nullable=True,
        comment="轉寄地址 (可選,例如外部郵箱)"
    )
    auto_reply = Column(
        Text,
        nullable=True,
        comment="自動回覆內容 (可選,例如休假通知)"
    )

    # 通用欄位
    is_active = Column(Boolean, default=True, nullable=False, comment="是否啟用")
    edit_by = Column(String(100), nullable=True, comment="最後編輯者")
    created_at = Column(DateTime, default=datetime.utcnow, nullable=False, comment="建立時間")
    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow, nullable=False)

    # 關聯
    employee = relationship("Employee", back_populates="email_accounts")
    tenant = relationship("Tenant")

    def __repr__(self):
        return f"<EmailAccount {self.email_address} (配額:{self.quota_mb}MB)>"

    @property
    def local_part(self) -> str:
        """郵件前綴 (@ 之前的部分)"""
        return self.email_address.split('@')[0] if '@' in self.email_address else self.email_address

    @property
    def domain_part(self) -> str:
        """網域部分 (@ 之後的部分)"""
        return self.email_address.split('@')[1] if '@' in self.email_address else ""

    @property
    def quota_gb(self) -> float:
        """配額 (GB,用於顯示)"""
        return round(self.quota_mb / 1024, 2)

    @classmethod
    def get_default_quota_by_level(cls, job_level: str) -> int:
        """根據職級取得預設配額 (MB)"""
        quota_map = {
            "Junior": 2048,
            "Mid": 3072,
            "Senior": 5120,
            "Manager": 10240,
        }
        return quota_map.get(job_level, 2048)