# auth.py - Keep security-critical validation
import re
from datetime import datetime

from pydantic import BaseModel, ConfigDict, EmailStr, Field, field_validator


class UserLogin(BaseModel):
    email_or_username: str = Field(..., description="Username or email address")
    password: str = Field(..., description="Password")
    vendor_code: str | None = Field(
        None, description="Optional vendor code for context"
    )

    @field_validator("email_or_username")
    @classmethod
    def validate_email_or_username(cls, v):
        return v.strip()


class UserResponse(BaseModel):
    model_config = ConfigDict(from_attributes=True)
    id: int
    email: str
    username: str
    role: str
    is_active: bool
    is_super_admin: bool = False
    preferred_language: str | None = None
    last_login: datetime | None = None
    created_at: datetime
    updated_at: datetime


class LoginResponse(BaseModel):
    access_token: str
    token_type: str = "bearer"
    expires_in: int
    user: UserResponse


class UserDetailResponse(UserResponse):
    """Extended user response with additional details."""

    first_name: str | None = None
    last_name: str | None = None
    full_name: str | None = None
    is_email_verified: bool = False
    owned_companies_count: int = 0
    vendor_memberships_count: int = 0


class UserUpdate(BaseModel):
    """Schema for updating user information."""

    username: str | None = Field(None, min_length=3, max_length=50)
    email: EmailStr | None = None
    first_name: str | None = Field(None, max_length=100)
    last_name: str | None = Field(None, max_length=100)
    role: str | None = Field(None, pattern="^(admin|vendor)$")
    is_active: bool | None = None
    is_email_verified: bool | None = None
    preferred_language: str | None = Field(
        None, description="Preferred language (en, fr, de, lb)"
    )

    @field_validator("username")
    @classmethod
    def validate_username(cls, v):
        if v and not re.match(r"^[a-zA-Z0-9_]+$", v):
            raise ValueError(
                "Username must contain only letters, numbers, or underscores"
            )
        return v.lower().strip() if v else v


class UserCreate(BaseModel):
    """Schema for creating a new user (admin only)."""

    email: EmailStr = Field(..., description="Valid email address")
    username: str = Field(..., min_length=3, max_length=50)
    password: str = Field(..., min_length=6, description="Password")
    first_name: str | None = Field(None, max_length=100)
    last_name: str | None = Field(None, max_length=100)
    role: str = Field(default="vendor", pattern="^(admin|vendor)$")
    preferred_language: str | None = Field(
        None, description="Preferred language (en, fr, de, lb)"
    )

    @field_validator("username")
    @classmethod
    def validate_username(cls, v):
        if not re.match(r"^[a-zA-Z0-9_]+$", v):
            raise ValueError(
                "Username must contain only letters, numbers, or underscores"
            )
        return v.lower().strip()


class UserListResponse(BaseModel):
    """Schema for paginated user list."""

    items: list[UserResponse]
    total: int
    page: int
    per_page: int
    pages: int


class UserSearchItem(BaseModel):
    """Schema for a single user search result."""

    id: int
    username: str
    email: str
    is_active: bool


class UserSearchResponse(BaseModel):
    """Schema for user search results."""

    users: list[UserSearchItem]


class UserStatusToggleResponse(BaseModel):
    """Schema for user status toggle response."""

    message: str
    is_active: bool


class UserDeleteResponse(BaseModel):
    """Schema for user delete response."""

    message: str


class LogoutResponse(BaseModel):
    """Schema for logout response."""

    message: str


class PasswordResetRequestResponse(BaseModel):
    """Schema for password reset request response."""

    message: str


class PasswordResetResponse(BaseModel):
    """Schema for password reset response."""

    message: str


class VendorUserResponse(BaseModel):
    """Schema for vendor user info in auth context."""

    id: int
    username: str
    email: str
    role: str
    is_active: bool

    model_config = {"from_attributes": True}


class UserContext(BaseModel):
    """
    User context for dependency injection in API endpoints.

    This schema replaces direct use of the User database model in API routes,
    following the principle that routes should not import database models directly.

    Used by:
    - get_current_admin_api / get_current_admin_from_cookie_or_header
    - get_current_vendor_api / get_current_vendor_from_cookie_or_header
    - get_current_super_admin

    For admin users:
    - is_super_admin indicates full platform access
    - accessible_platform_ids is None for super admins (all platforms)
    - accessible_platform_ids is a list for platform admins

    For vendor users:
    - token_vendor_id/code/role come from JWT token
    - These indicate which vendor context the user is operating in
    """

    # Core user fields
    id: int
    email: str
    username: str
    role: str  # "admin" or "vendor"
    is_active: bool = True

    # Admin-specific fields
    is_super_admin: bool = False
    accessible_platform_ids: list[int] | None = None  # None = all platforms (super admin)

    # Vendor-specific fields (from JWT token)
    token_vendor_id: int | None = None
    token_vendor_code: str | None = None
    token_vendor_role: str | None = None

    # Optional profile fields
    first_name: str | None = None
    last_name: str | None = None
    preferred_language: str | None = None

    model_config = ConfigDict(from_attributes=True)

    @property
    def full_name(self) -> str:
        """Returns the full name of the user."""
        if self.first_name and self.last_name:
            return f"{self.first_name} {self.last_name}"
        return self.username

    @property
    def is_admin(self) -> bool:
        """Check if user is a platform admin."""
        return self.role == "admin"

    @property
    def is_vendor(self) -> bool:
        """Check if user is a vendor."""
        return self.role == "vendor"

    @classmethod
    def from_user(cls, user, include_vendor_context: bool = True) -> "UserContext":
        """
        Create UserContext from a User database model.

        Args:
            user: User database model instance
            include_vendor_context: Whether to include token_vendor_* fields

        Returns:
            UserContext instance
        """
        data = {
            "id": user.id,
            "email": user.email,
            "username": user.username,
            "role": user.role,
            "is_active": user.is_active,
            "is_super_admin": getattr(user, "is_super_admin", False),
            "first_name": getattr(user, "first_name", None),
            "last_name": getattr(user, "last_name", None),
            "preferred_language": getattr(user, "preferred_language", None),
        }

        # Add admin platform access info
        if user.role == "admin":
            if getattr(user, "is_super_admin", False):
                data["accessible_platform_ids"] = None  # All platforms
            else:
                # Get platform IDs from admin_platforms relationship
                admin_platforms = getattr(user, "admin_platforms", [])
                data["accessible_platform_ids"] = [
                    ap.platform_id for ap in admin_platforms if ap.is_active
                ]

        # Add vendor context from JWT token if present
        if include_vendor_context:
            data["token_vendor_id"] = getattr(user, "token_vendor_id", None)
            data["token_vendor_code"] = getattr(user, "token_vendor_code", None)
            data["token_vendor_role"] = getattr(user, "token_vendor_role", None)

        return cls(**data)