"""
═══════════════════════════════════════════════════════════════════
DATA HUB API ROUTER
REST API endpoints for accessing collected crypto data
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This router provides REST API endpoints for the frontend to access:
- Market prices (latest, top coins, bulk queries)
- OHLCV candlestick data (for charts)
- News articles (with filtering)
- Sentiment indicators (Fear & Greed, etc.)
- Whale transactions (large movements)
- Provider health status
- System statistics

All data is served from the backend database via DataHubService.

@version 1.0.0
@author Crypto Intelligence Hub
"""

from typing import List, Optional
from fastapi import APIRouter, HTTPException, Query
from pydantic import BaseModel

from backend.services.data_hub_service import DataHubService

# Initialize router
router = APIRouter(prefix="/api/hub", tags=["Data Hub"])

# Initialize service
hub_service = DataHubService()


# ═══════════════════════════════════════════════════════════════════
# RESPONSE MODELS
# ═══════════════════════════════════════════════════════════════════

class PriceResponse(BaseModel):
    """Response model for price data"""
    symbol: str
    price_usd: float
    change_1h: Optional[float]
    change_24h: Optional[float]
    change_7d: Optional[float]
    volume_24h: Optional[float]
    market_cap: Optional[float]
    circulating_supply: Optional[float]
    total_supply: Optional[float]
    sources_count: int
    sources: List[str]
    collected_at: str


class FearGreedResponse(BaseModel):
    """Response model for Fear & Greed Index"""
    value: float
    classification: str
    source: str
    collected_at: str


class NewsArticleResponse(BaseModel):
    """Response model for news articles"""
    title: str
    url: str
    content: Optional[str]
    summary: Optional[str]
    source: str
    author: Optional[str]
    published_at: str
    sentiment: Optional[str]
    sentiment_score: Optional[float]
    related_symbols: List[str]
    collected_at: str


class WhaleTransactionResponse(BaseModel):
    """Response model for whale transactions"""
    tx_hash: str
    blockchain: str
    from_address: str
    to_address: str
    amount: float
    symbol: str
    usd_value: float
    tx_time: str
    block_number: Optional[int]
    source: str
    collected_at: str


# ═══════════════════════════════════════════════════════════════════
# MARKET DATA ENDPOINTS
# ═══════════════════════════════════════════════════════════════════

@router.get("/price/{symbol}", summary="Get latest price for a symbol")
def get_price(symbol: str):
    """
    Get the latest price data for a specific cryptocurrency

    Args:
        symbol: Cryptocurrency symbol (e.g., 'BTC', 'ETH')

    Returns:
        Price data from the most recent collection
    """
    price = hub_service.get_latest_price(symbol)

    if not price:
        raise HTTPException(
            status_code=404,
            detail=f"No price data found for symbol: {symbol}"
        )

    return price


@router.get("/prices/top", summary="Get top cryptocurrencies by market cap")
def get_top_coins(limit: int = Query(100, ge=1, le=500)):
    """
    Get top cryptocurrencies ranked by market capitalization

    Args:
        limit: Maximum number of coins to return (1-500)

    Returns:
        List of top coins with price and market data
    """
    coins = hub_service.get_top_coins(limit=limit)
    return {"count": len(coins), "coins": coins}


@router.post("/prices/bulk", summary="Get prices for multiple symbols")
def get_bulk_prices(symbols: List[str]):
    """
    Get latest prices for multiple symbols in a single request

    Args:
        symbols: List of cryptocurrency symbols

    Returns:
        Dictionary mapping symbols to price data
    """
    if not symbols:
        raise HTTPException(status_code=400, detail="Symbols list cannot be empty")

    if len(symbols) > 100:
        raise HTTPException(status_code=400, detail="Maximum 100 symbols per request")

    prices = hub_service.get_prices_bulk(symbols)
    return {"count": len(prices), "prices": prices}


# ═══════════════════════════════════════════════════════════════════
# OHLCV DATA ENDPOINTS (for charts)
# ═══════════════════════════════════════════════════════════════════

@router.get("/ohlcv/{symbol}", summary="Get OHLCV candlestick data for charting")
def get_ohlcv(
    symbol: str,
    timeframe: str = Query("1h", regex="^(1m|5m|15m|1h|4h|1d|1w)$"),
    limit: int = Query(100, ge=1, le=1000),
    source: Optional[str] = None
):
    """
    Get OHLCV (Open, High, Low, Close, Volume) candlestick data

    Args:
        symbol: Cryptocurrency symbol
        timeframe: Candle timeframe (1m, 5m, 15m, 1h, 4h, 1d, 1w)
        limit: Number of candles to return (1-1000)
        source: Specific data source (optional)

    Returns:
        List of OHLCV candles in chronological order
    """
    candles = hub_service.get_ohlcv(
        symbol=symbol,
        timeframe=timeframe,
        limit=limit,
        source=source
    )

    return {"count": len(candles), "candles": candles}


# ═══════════════════════════════════════════════════════════════════
# SENTIMENT ENDPOINTS
# ═══════════════════════════════════════════════════════════════════

@router.get("/fear-greed", summary="Get Fear & Greed Index")
def get_fear_greed():
    """
    Get the latest Fear & Greed Index value

    The Fear & Greed Index is a market sentiment indicator that ranges
    from 0 (Extreme Fear) to 100 (Extreme Greed).

    Returns:
        Current Fear & Greed Index value and classification
    """
    sentiment = hub_service.get_fear_greed()

    if not sentiment:
        raise HTTPException(
            status_code=404,
            detail="No Fear & Greed data available"
        )

    return sentiment


@router.get("/sentiment/history", summary="Get sentiment history")
def get_sentiment_history(
    indicator: str = Query("fear_greed"),
    days: int = Query(30, ge=1, le=365)
):
    """
    Get historical sentiment data for charting

    Args:
        indicator: Sentiment indicator name (default: fear_greed)
        days: Number of days of history (1-365)

    Returns:
        List of sentiment data points over time
    """
    history = hub_service.get_sentiment_history(
        indicator=indicator,
        days=days
    )

    return {"count": len(history), "data": history}


# ═══════════════════════════════════════════════════════════════════
# NEWS ENDPOINTS
# ═══════════════════════════════════════════════════════════════════

@router.get("/news", summary="Get latest news articles")
def get_news(
    limit: int = Query(50, ge=1, le=200),
    source: Optional[str] = None,
    symbol: Optional[str] = None
):
    """
    Get latest cryptocurrency news articles

    Args:
        limit: Maximum number of articles (1-200)
        source: Filter by news source (optional)
        symbol: Filter by related cryptocurrency (optional)

    Returns:
        List of news articles with sentiment analysis
    """
    articles = hub_service.get_news(
        limit=limit,
        source=source,
        symbol=symbol
    )

    return {"count": len(articles), "articles": articles}


# ═══════════════════════════════════════════════════════════════════
# WHALE TRANSACTION ENDPOINTS
# ═══════════════════════════════════════════════════════════════════

@router.get("/whales", summary="Get whale transaction alerts")
def get_whale_alerts(
    min_usd: float = Query(1000000, ge=100000),
    limit: int = Query(50, ge=1, le=200),
    blockchain: Optional[str] = None
):
    """
    Get recent large cryptocurrency transactions

    Args:
        min_usd: Minimum transaction value in USD (default: $1M)
        limit: Maximum number of transactions (1-200)
        blockchain: Filter by blockchain (optional)

    Returns:
        List of whale transactions
    """
    transactions = hub_service.get_whale_alerts(
        min_usd=min_usd,
        limit=limit,
        blockchain=blockchain
    )

    return {"count": len(transactions), "transactions": transactions}


# ═══════════════════════════════════════════════════════════════════
# SYSTEM STATUS ENDPOINTS
# ═══════════════════════════════════════════════════════════════════

@router.get("/sources/status", summary="Get data source health status")
def get_provider_status():
    """
    Get health status of all data collection sources

    Returns:
        Health information for all API providers including:
        - Status (healthy/degraded/down)
        - Response times
        - Error counts
        - Last success/failure times
    """
    return hub_service.get_provider_status()


@router.get("/stats", summary="Get Data Hub statistics")
def get_stats():
    """
    Get comprehensive Data Hub statistics

    Returns:
        Statistics including:
        - Total records by type
        - Last collection time
        - Total records across all tables
    """
    return hub_service.get_stats()


# ═══════════════════════════════════════════════════════════════════
# HEALTH CHECK
# ═══════════════════════════════════════════════════════════════════

@router.get("/health", summary="API health check")
def health_check():
    """
    Simple health check endpoint

    Returns:
        API status and version
    """
    return {
        "status": "healthy",
        "service": "Data Hub API",
        "version": "1.0.0"
    }


# Export router
__all__ = ['router']