from __future__ import annotations

from datetime import datetime
from typing import List, Optional

from pydantic import BaseModel, Field, HttpUrl


class EpisodeInfo(BaseModel):
    """Information about a single episode."""

    episode_number: int = Field(..., ge=1, description="Episode index (1-based)")
    title: Optional[str] = Field(None, description="Optional episode title")
    aired_at: Optional[datetime] = Field(None, description="Air date/time if known")
    duration_seconds: Optional[int] = Field(None, ge=0, description="Duration in seconds")
    available: bool = Field(True, description="Whether the episode is available for download")
    sources: List[HttpUrl] = Field(default_factory=list, description="List of known streaming/download source URLs")


class MissingEpisodeInfo(BaseModel):
    """Represents a gap in the episode list for a series."""

    from_episode: int = Field(..., ge=1, description="Starting missing episode number")
    to_episode: int = Field(..., ge=1, description="Ending missing episode number (inclusive)")
    reason: Optional[str] = Field(None, description="Optional explanation why episodes are missing")

    @property
    def count(self) -> int:
        """Number of missing episodes in the range."""
        return max(0, self.to_episode - self.from_episode + 1)


class AnimeSeriesResponse(BaseModel):
    """Response model for a series with metadata and episodes."""

    id: str = Field(..., description="Unique series identifier")
    title: str = Field(..., description="Series title")
    alt_titles: List[str] = Field(default_factory=list, description="Alternative titles")
    description: Optional[str] = Field(None, description="Short series description")
    total_episodes: Optional[int] = Field(None, ge=0, description="Declared total episode count if known")
    episodes: List[EpisodeInfo] = Field(default_factory=list, description="Known episodes information")
    missing_episodes: List[MissingEpisodeInfo] = Field(default_factory=list, description="Detected missing episode ranges")
    thumbnail: Optional[HttpUrl] = Field(None, description="Optional thumbnail image URL")


class SearchRequest(BaseModel):
    """Request payload for searching series."""

    query: str = Field(..., min_length=1)
    limit: int = Field(10, ge=1, le=100)
    include_adult: bool = Field(False)


class SearchResult(BaseModel):
    """Search result item for a series discovery endpoint."""

    id: str
    title: str
    snippet: Optional[str] = None
    thumbnail: Optional[HttpUrl] = None
    score: Optional[float] = None