from __future__ import annotations

import re
from datetime import datetime
from typing import Any, Optional

from pydantic import BaseModel, EmailStr, Field, field_validator


def _validate_password(v: str) -> str:
    if len(v) < 8:
        raise ValueError("Password must be at least 8 characters")
    if len(v) > 128:
        raise ValueError("Password must not exceed 128 characters")
    if not re.search(r"[A-Z]", v):
        raise ValueError("Password must contain at least one uppercase letter")
    if not re.search(r"[a-z]", v):
        raise ValueError("Password must contain at least one lowercase letter")
    if not re.search(r"\d", v):
        raise ValueError("Password must contain at least one digit")
    return v


class RegisterSchema(BaseModel):
    email: EmailStr
    password: str
    username: Optional[str] = Field(None, min_length=2, max_length=50, pattern=r"^[a-zA-Z0-9_]+$")
    full_name: Optional[str] = Field(None, min_length=1, max_length=100)

    _validate_password = field_validator("password")(_validate_password)


class LoginSchema(BaseModel):
    email: EmailStr
    password: str


class TokenData(BaseModel):
    access_token: str
    refresh_token: str
    token_type: str = "bearer"


class TokenRefreshSchema(BaseModel):
    refresh_token: str


class UserProfile(BaseModel):
    id: str
    email: str
    username: Optional[str] = None
    full_name: Optional[str] = None
    is_active: bool
    is_verified: bool
    roles: list[str]
    created_at: datetime

    @field_validator("roles", mode="before")
    @classmethod
    def _extract_role_names(cls, v: Any) -> list[str]:
        if not v:
            return []
        if isinstance(v[0], str):
            return v
        return [r.name for r in v]

    model_config = {"from_attributes": True}


class UpdateProfileSchema(BaseModel):
    username: Optional[str] = Field(None, min_length=2, max_length=50, pattern=r"^[a-zA-Z0-9_]+$")
    full_name: Optional[str] = Field(None, min_length=1, max_length=100)


class ChangePasswordSchema(BaseModel):
    current_password: str
    new_password: str

    _validate_new_password = field_validator("new_password")(_validate_password)


class ForgotPasswordSchema(BaseModel):
    email: EmailStr


class ResetPasswordSchema(BaseModel):
    token: str
    new_password: str

    _validate_new_password = field_validator("new_password")(_validate_password)


class SessionOut(BaseModel):
    id: str
    device_info: Optional[str] = None
    ip_address: Optional[str] = None
    created_at: datetime
    expires_at: datetime

    model_config = {"from_attributes": True}


class MessageResponse(BaseModel):
    message: str


class UserSchemaField(BaseModel):
    field: str
    type: str
    required: bool
    description: str
    constraints: Optional[str] = None


class UserSchemaResponse(BaseModel):
    table_name: str = "users"
    columns: list[UserSchemaField]


# --- Wrapped API response schemas ---

class ApiResponse(BaseModel):
    success: bool = True


class DataResponse(ApiResponse):
    data: dict
    application_id: Optional[str] = None
    warning: Optional[dict] = None


class TokenResponse(ApiResponse):
    data: TokenData
    application_id: Optional[str] = None
    warning: Optional[dict] = None


class ProfileResponse(ApiResponse):
    data: UserProfile
    application_id: Optional[str] = None
    warning: Optional[dict] = None


class MessageDataResponse(ApiResponse):
    data: MessageResponse
    application_id: Optional[str] = None
    warning: Optional[dict] = None


class SchemaResponse(ApiResponse):
    data: UserSchemaResponse
    application_id: Optional[str] = None
    warning: Optional[dict] = None


class SessionListResponse(ApiResponse):
    data: list[SessionOut]
    application_id: Optional[str] = None
    warning: Optional[dict] = None