from pydantic import BaseModel, Field, HttpUrl, validator
from typing import List, Literal, Union
from datetime import datetime
from enum import Enum


class VerdictEnum(str, Enum):
    TRUE = "True"
    FALSE = "False"
    PARTIALLY_TRUE = "Partially True"
    UNVERIFIED = "Unverified"


class ConfidenceEnum(str, Enum):
    HIGH = "High"
    MEDIUM = "Medium"
    LOW = "Low"


class FactCheckRequest(BaseModel):
    query: str = Field(
        ...,
        min_length=3,
        max_length=500,
        description="The claim or statement to be fact-checked",
        example="Did NASA confirm finding alien structures on Mars in 2024?",
    )


class Source(BaseModel):
    url: str
    name: str = ""

    @validator("url")
    def validate_url(cls, v):
        # Basic URL validation without requiring HTTP/HTTPS
        if not v or len(v) < 3:
            raise ValueError("URL must not be empty and must be at least 3 characters")
        return v


class FactCheckResponse(BaseModel):
    claim: str = Field(
        ...,
        min_length=10,
        max_length=1000,
        description="The exact claim being verified",
    )
    verdict: VerdictEnum = Field(..., description="The verification verdict")
    confidence: ConfidenceEnum = Field(
        ..., description="Confidence level in the verdict"
    )
    sources: List[Source] = Field(
        ..., min_items=1, description="List of sources used in verification"
    )
    evidence: str = Field(
        ...,
        min_length=20,
        max_length=500,
        description="Concise summary of key evidence",
    )
    explanation: str = Field(
        ...,
        min_length=50,
        max_length=1000,
        description="Detailed explanation of verification findings",
    )
    additional_context: str = Field(
        ...,
        min_length=20,
        max_length=500,
        description="Important context about the verification",
    )

    class Config:
        json_schema_extra = {
            "example": {
                "claim": "NASA confirmed finding alien structures on Mars in 2024",
                "verdict": "False",
                "confidence": "High",
                "sources": [
                    {
                        "url": "https://www.nasa.gov/mars-exploration",
                        "name": "NASA Mars Exploration",
                    },
                    {
                        "url": "https://factcheck.org/2024/mars-claims",
                        "name": "FactCheck.org",
                    },
                ],
                "evidence": "NASA has made no such announcement. Recent Mars rover images show natural rock formations.",
                "explanation": "Multiple fact-checking organizations investigated this claim. NASA's official communications and Mars mission reports from 2024 contain no mention of alien structures. The viral images being shared are misidentified natural geological formations.",
                "additional_context": "Similar false claims about alien structures on Mars have circulated periodically since the first Mars rovers began sending back images.",
            }
        }


class ErrorResponse(BaseModel):
    detail: str
    error_code: str = Field(..., example="VALIDATION_ERROR")
    path: str = Field(..., example="/check-facts")