import json
from pydantic import BaseModel, field_validator
from typing import Optional, Dict, Any, Literal, List
from datetime import datetime


class VasTicketBase(BaseModel):
    status: Optional[
        Literal['pending', 'info_required', 'resolved', 'rejected']
    ] = None

    admin_comment: Optional[str] = None
    extra_fields: Optional[Dict[str, Any]] = None
    
    @field_validator("extra_fields", mode="before")
    def normalize_json_field(cls, v):
        if v is None:
            return None
        if isinstance(v, str):
            try:
                return json.loads(v)
            except Exception:
                return {}
        return v

class VasTicketCreate(BaseModel):
    order_id: str
    
    type: Literal['refund', 'dispute', 'change_request']
    reason: Optional[str]

class VasTicketOut(VasTicketBase):
    id: int
    order_id: str
    user_id: str

    type: str
    reason: Optional[str]

    created_at: datetime
    updated_at: datetime

    model_config = {
        "from_attributes": True
    }

class VasTicketStatusUpdate(BaseModel):
    status: Literal["resolved", "info_required", "rejected"]
    comment: str
    
class VasTicketMessageBase(BaseModel):
    ticket_id: int
    sender_type: Literal["user", "admin", "system"]
    sender_id: Optional[str] = None
    content: Optional[str] = None
    attachments: Optional[Dict[str, Any]] = None
    @field_validator("attachments", mode="before")
    def normalize_json_field(cls, v):
        if v is None:
            return None
        if isinstance(v, str):
            try:
                return json.loads(v)
            except Exception:
                return {}
        return v


class VasTicketMessageCreate(BaseModel):
    content: str
    attachments: Optional[dict] = None

class VasTicketMessageOut(VasTicketMessageBase):
    id: int
    created_at: datetime
    
    model_config = {
        "from_attributes": True
    }