"""
Base classes and standardized response models for external APIs.

All provider implementations should return these standard models
to ensure interoperability when swapping providers.
"""

from abc import ABC, abstractmethod
from dataclasses import dataclass, field
from datetime import datetime
from typing import Optional
from enum import Enum


# =============================================================================
# Weather Models
# =============================================================================

class WeatherCondition(Enum):
    """Standardized weather conditions across providers."""
    CLEAR = "clear"
    PARTLY_CLOUDY = "partly_cloudy"
    CLOUDY = "cloudy"
    OVERCAST = "overcast"
    FOG = "fog"
    DRIZZLE = "drizzle"
    RAIN = "rain"
    HEAVY_RAIN = "heavy_rain"
    SNOW = "snow"
    HEAVY_SNOW = "heavy_snow"
    THUNDERSTORM = "thunderstorm"
    UNKNOWN = "unknown"


@dataclass
class CurrentWeather:
    """Standardized current weather response."""
    temperature: float  # Celsius
    feels_like: Optional[float]  # Celsius
    humidity: int  # Percentage 0-100
    wind_speed: float  # km/h
    wind_direction: Optional[int]  # Degrees 0-360
    condition: WeatherCondition
    condition_text: str  # Human-readable description
    timestamp: datetime
    location: str  # City/location name
    uv_index: Optional[float] = None  # UV index 0-11+

    def to_text(self) -> str:
        """Generate natural language description."""
        parts = [
            f"Currently {self.temperature:.1f}°C",
            f"({self.condition_text}) in {self.location}.",
            f"Humidity {self.humidity}%, wind {self.wind_speed:.0f} km/h."
        ]
        if self.uv_index is not None:
            parts.append(f"UV index: {self.uv_index:.0f}.")
        return " ".join(parts)


@dataclass
class DayForecast:
    """Standardized daily forecast."""
    date: datetime
    temp_high: float  # Celsius
    temp_low: float  # Celsius
    condition: WeatherCondition
    condition_text: str
    precipitation_chance: Optional[int]  # Percentage 0-100
    precipitation_mm: Optional[float]
    uv_index_max: Optional[float] = None  # Max UV index for the day

    def to_text(self) -> str:
        """Generate natural language description."""
        date_str = self.date.strftime("%A")  # Day name
        precip = f", {self.precipitation_chance}% rain" if self.precipitation_chance else ""
        uv = f", UV {self.uv_index_max:.0f}" if self.uv_index_max else ""
        return f"{date_str}: {self.temp_high:.0f}°/{self.temp_low:.0f}°C, {self.condition_text}{precip}{uv}"


@dataclass
class WeatherForecast:
    """Standardized forecast response."""
    location: str
    current: CurrentWeather
    daily: list[DayForecast] = field(default_factory=list)


@dataclass
class GeoLocation:
    """Geocoding result."""
    name: str
    latitude: float
    longitude: float
    country: Optional[str] = None
    admin_area: Optional[str] = None  # State/province


@dataclass
class SunTimes:
    """Sunrise/sunset times for a location."""
    location: str
    date: datetime
    sunrise: datetime
    sunset: datetime
    daylight_duration: int  # seconds
    solar_noon: Optional[datetime] = None

    def to_text(self) -> str:
        """Generate natural language description."""
        sunrise_str = self.sunrise.strftime("%H:%M")
        sunset_str = self.sunset.strftime("%H:%M")
        hours = self.daylight_duration // 3600
        minutes = (self.daylight_duration % 3600) // 60
        return (
            f"Sun times for {self.location} on {self.date.strftime('%A %d %B')}: "
            f"Sunrise at {sunrise_str}, sunset at {sunset_str}. "
            f"Daylight duration: {hours}h {minutes}m."
        )


@dataclass
class AirQuality:
    """Air quality measurements for a location."""
    location: str
    timestamp: datetime
    aqi_european: Optional[int]  # European AQI 0-500+
    aqi_us: Optional[int]  # US AQI 0-500+
    pm2_5: Optional[float]  # µg/m³
    pm10: Optional[float]  # µg/m³
    ozone: Optional[float]  # µg/m³
    nitrogen_dioxide: Optional[float]  # µg/m³
    sulphur_dioxide: Optional[float]  # µg/m³
    carbon_monoxide: Optional[float]  # µg/m³
    # Pollen (European data only, seasonal)
    pollen_grass: Optional[float] = None
    pollen_birch: Optional[float] = None
    pollen_alder: Optional[float] = None

    def to_text(self) -> str:
        """Generate natural language description."""
        parts = [f"Air quality in {self.location}:"]
        if self.aqi_european is not None:
            level = self._aqi_level(self.aqi_european)
            parts.append(f"European AQI {self.aqi_european} ({level}).")
        if self.pm2_5 is not None:
            parts.append(f"PM2.5: {self.pm2_5:.1f} µg/m³.")
        if self.pm10 is not None:
            parts.append(f"PM10: {self.pm10:.1f} µg/m³.")
        if self.ozone is not None:
            parts.append(f"Ozone: {self.ozone:.1f} µg/m³.")
        return " ".join(parts)

    @staticmethod
    def _aqi_level(aqi: int) -> str:
        """Convert AQI to human-readable level."""
        if aqi <= 20:
            return "good"
        elif aqi <= 40:
            return "fair"
        elif aqi <= 60:
            return "moderate"
        elif aqi <= 80:
            return "poor"
        elif aqi <= 100:
            return "very poor"
        else:
            return "hazardous"


# =============================================================================
# News Models
# =============================================================================

@dataclass
class NewsItem:
    """Standardized news article/item."""
    title: str
    description: Optional[str]
    url: str
    published: Optional[datetime]
    source: str  # e.g., "nos", "bbc"
    category: Optional[str] = None  # e.g., "tech", "world"
    image_url: Optional[str] = None


@dataclass
class NewsFeed:
    """Standardized news feed response."""
    source: str
    category: str
    items: list[NewsItem] = field(default_factory=list)
    fetched_at: datetime = field(default_factory=datetime.now)

    def to_text(self) -> str:
        """Generate natural language summary of headlines."""
        if not self.items:
            return f"No news available from {self.source}."

        headlines = [f"- {item.title}" for item in self.items[:5]]
        return f"Headlines from {self.source} ({self.category}):\n" + "\n".join(headlines)


# =============================================================================
# Financial Models
# =============================================================================

@dataclass
class StockQuote:
    """Standardized stock/crypto quote."""
    symbol: str
    name: Optional[str]
    price: float
    currency: str  # e.g., "USD", "EUR"
    change: Optional[float]  # Absolute change
    change_percent: Optional[float]  # Percentage change
    timestamp: datetime

    def to_text(self) -> str:
        """Generate natural language description."""
        change_str = ""
        if self.change is not None and self.change_percent is not None:
            direction = "up" if self.change >= 0 else "down"
            change_str = f", {direction} {abs(self.change_percent):.2f}%"
        return f"{self.symbol}: {self.price:.2f} {self.currency}{change_str}"


# =============================================================================
# Provider Interfaces
# =============================================================================

class WeatherProvider(ABC):
    """Abstract base class for weather API providers."""

    @abstractmethod
    async def geocode(self, city: str) -> Optional[GeoLocation]:
        """Convert city name to coordinates."""
        pass

    @abstractmethod
    async def get_current(self, location: GeoLocation) -> CurrentWeather:
        """Get current weather for a location."""
        pass

    @abstractmethod
    async def get_forecast(self, location: GeoLocation, days: int = 7) -> WeatherForecast:
        """Get weather forecast for a location."""
        pass

    @abstractmethod
    async def get_sun_times(self, location: GeoLocation) -> SunTimes:
        """Get sunrise/sunset times for today."""
        pass

    async def get_weather_for_city(self, city: str) -> CurrentWeather:
        """Convenience method: geocode and get current weather."""
        location = await self.geocode(city)
        if not location:
            raise ValueError(f"Could not geocode city: {city}")
        return await self.get_current(location)


class AirQualityProvider(ABC):
    """Abstract base class for air quality API providers."""

    @abstractmethod
    async def get_air_quality(self, location: GeoLocation) -> AirQuality:
        """Get current air quality for a location."""
        pass


class NewsProvider(ABC):
    """Abstract base class for news API providers."""

    @property
    @abstractmethod
    def source_name(self) -> str:
        """Provider name (e.g., 'nos', 'bbc')."""
        pass

    @property
    @abstractmethod
    def available_categories(self) -> list[str]:
        """List of available category keys."""
        pass

    @abstractmethod
    async def get_feed(self, category: str, limit: int = 10) -> NewsFeed:
        """Get news feed for a category."""
        pass

    async def get_headlines(self, categories: list[str], limit: int = 5) -> list[NewsFeed]:
        """Get headlines from multiple categories."""
        feeds = []
        for cat in categories:
            if cat in self.available_categories:
                feed = await self.get_feed(cat, limit)
                feeds.append(feed)
        return feeds


class FinancialProvider(ABC):
    """Abstract base class for financial API providers."""

    @abstractmethod
    async def get_quote(self, symbol: str) -> Optional[StockQuote]:
        """Get current quote for a stock/crypto symbol."""
        pass

    @abstractmethod
    async def get_quotes(self, symbols: list[str]) -> list[StockQuote]:
        """Get quotes for multiple symbols."""
        pass