"""
權限 Schemas
"""
from datetime import datetime
from typing import Optional
from pydantic import BaseModel, Field, ConfigDict, field_validator

from app.schemas.base import BaseSchema, TimestampSchema


# 系統名稱常數
VALID_SYSTEMS = ["gitea", "portainer", "traefik", "keycloak"]

# 存取層級常數
VALID_ACCESS_LEVELS = ["admin", "user", "readonly"]


class PermissionBase(BaseSchema):
    """權限基礎 Schema"""

    system_name: str = Field(..., description="系統名稱: gitea, portainer, traefik, keycloak")
    access_level: str = Field("user", description="存取層級: admin, user, readonly")

    @field_validator('system_name')
    @classmethod
    def validate_system_name(cls, v):
        """驗證系統名稱"""
        if v.lower() not in VALID_SYSTEMS:
            raise ValueError(f"system_name 必須是以下之一: {', '.join(VALID_SYSTEMS)}")
        return v.lower()

    @field_validator('access_level')
    @classmethod
    def validate_access_level(cls, v):
        """驗證存取層級"""
        if v.lower() not in VALID_ACCESS_LEVELS:
            raise ValueError(f"access_level 必須是以下之一: {', '.join(VALID_ACCESS_LEVELS)}")
        return v.lower()


class PermissionCreate(PermissionBase):
    """創建權限 Schema"""

    employee_id: int = Field(..., description="員工 ID")
    granted_by: Optional[int] = Field(None, description="授予人 ID")

    model_config = ConfigDict(
        json_schema_extra={
            "example": {
                "employee_id": 1,
                "system_name": "gitea",
                "access_level": "user",
                "granted_by": 2
            }
        }
    )


class PermissionUpdate(BaseSchema):
    """更新權限 Schema"""

    access_level: str = Field(..., description="存取層級: admin, user, readonly")
    granted_by: Optional[int] = Field(None, description="授予人 ID")

    @field_validator('access_level')
    @classmethod
    def validate_access_level(cls, v):
        """驗證存取層級"""
        if v.lower() not in VALID_ACCESS_LEVELS:
            raise ValueError(f"access_level 必須是以下之一: {', '.join(VALID_ACCESS_LEVELS)}")
        return v.lower()


class PermissionInDB(PermissionBase):
    """資料庫中的權限 Schema"""

    id: int
    tenant_id: int
    employee_id: int
    granted_at: datetime
    granted_by: Optional[int] = None

    model_config = ConfigDict(from_attributes=True)


class PermissionResponse(PermissionInDB):
    """權限響應 Schema (包含關聯資料)"""

    employee_name: Optional[str] = Field(None, description="員工姓名")
    employee_number: Optional[str] = Field(None, description="員工編號")
    granted_by_name: Optional[str] = Field(None, description="授予人姓名")

    model_config = ConfigDict(
        json_schema_extra={
            "example": {
                "id": 1,
                "tenant_id": 1,
                "employee_id": 1,
                "system_name": "gitea",
                "access_level": "admin",
                "granted_at": "2020-01-01T00:00:00",
                "granted_by": 2,
                "employee_name": "陳保時",
                "employee_number": "EMP001",
                "granted_by_name": "管理員"
            }
        }
    )


class PermissionListItem(BaseSchema):
    """權限列表項 Schema (簡化版)"""

    id: int
    employee_id: int
    system_name: str
    access_level: str
    granted_at: datetime
    employee_name: Optional[str] = None
    employee_number: Optional[str] = None

    model_config = ConfigDict(from_attributes=True)


class PermissionBatchCreate(BaseSchema):
    """批量創建權限 Schema"""

    employee_id: int = Field(..., description="員工 ID")
    permissions: list[PermissionBase] = Field(..., description="權限列表")
    granted_by: Optional[int] = Field(None, description="授予人 ID")

    model_config = ConfigDict(
        json_schema_extra={
            "example": {
                "employee_id": 1,
                "permissions": [
                    {"system_name": "gitea", "access_level": "user"},
                    {"system_name": "portainer", "access_level": "readonly"}
                ],
                "granted_by": 2
            }
        }
    )


class PermissionFilter(BaseSchema):
    """權限篩選 Schema"""

    employee_id: Optional[int] = Field(None, description="員工 ID")
    system_name: Optional[str] = Field(None, description="系統名稱")
    access_level: Optional[str] = Field(None, description="存取層級")

    @field_validator('system_name')
    @classmethod
    def validate_system_name(cls, v):
        """驗證系統名稱"""
        if v and v.lower() not in VALID_SYSTEMS:
            raise ValueError(f"system_name 必須是以下之一: {', '.join(VALID_SYSTEMS)}")
        return v.lower() if v else None

    @field_validator('access_level')
    @classmethod
    def validate_access_level(cls, v):
        """驗證存取層級"""
        if v and v.lower() not in VALID_ACCESS_LEVELS:
            raise ValueError(f"access_level 必須是以下之一: {', '.join(VALID_ACCESS_LEVELS)}")
        return v.lower() if v else None