const express = require('express');
const router = express.Router();
const { catchAsync } = require('../middleware/errorHandler');
const { logger } = require('../utils/logger');
const {
  getCurrentPrice,
  getCurrentPrices,
  getHistoricalData,
  getPriceUpdateStats
} = require('../services/priceUpdateService');
const {
  getHistoricalCandles,
  validateCandles,
  generateTestCandles
} = require('../services/candlestickService');

// GET /api/prices/current/:symbol
router.get('/current/:symbol', catchAsync(async (req, res) => {
  const { symbol } = req.params;

  if (!symbol) {
    return res.status(400).json({
      status: 'error',
      message: 'Symbol parameter is required'
    });
  }

  const priceData = getCurrentPrice(symbol.toUpperCase());

  if (!priceData) {
    return res.status(404).json({
      status: 'error',
      message: `Price data not found for symbol: ${symbol}`
    });
  }

  res.json({
    status: 'success',
    data: {
      symbol: priceData.symbol,
      price: priceData.close,
      change: priceData.close - priceData.open,
      changePercent: ((priceData.close - priceData.open) / priceData.open) * 100,
      high: priceData.high,
      low: priceData.low,
      volume: priceData.volume,
      timestamp: priceData.timestamp,
      timeframe: priceData.timeframe
    }
  });
}));

// GET /api/prices/current
router.get('/current', catchAsync(async (req, res) => {
  const { symbols } = req.query;

  let targetSymbols = null;
  if (symbols) {
    targetSymbols = symbols.split(',').map(s => s.trim().toUpperCase());
  }

  const pricesData = getCurrentPrices(targetSymbols);

  const formattedData = Object.entries(pricesData).map(([symbol, data]) => ({
    symbol,
    price: data.close,
    change: data.close - data.open,
    changePercent: ((data.close - data.open) / data.open) * 100,
    high: data.high,
    low: data.low,
    volume: data.volume,
    timestamp: data.timestamp,
    timeframe: data.timeframe
  }));

  res.json({
    status: 'success',
    data: formattedData,
    count: formattedData.length
  });
}));

// GET /api/prices/historical/:symbol
router.get('/historical/:symbol', catchAsync(async (req, res) => {
  const { symbol } = req.params;
  const { timeframe = 'H1', limit = 1000 } = req.query;

  if (!symbol) {
    return res.status(400).json({
      status: 'error',
      message: 'Symbol parameter is required'
    });
  }

  const historicalData = await getHistoricalData(
    symbol.toUpperCase(),
    timeframe,
    parseInt(limit)
  );

  if (historicalData.length === 0) {
    return res.status(404).json({
      status: 'error',
      message: `Historical data not found for symbol: ${symbol}`
    });
  }

  res.json({
    status: 'success',
    data: historicalData,
    symbol: symbol.toUpperCase(),
    timeframe,
    count: historicalData.length,
    meta: {
      requestedLimit: parseInt(limit),
      actualCount: historicalData.length,
      startDate: historicalData[0]?.timestamp,
      endDate: historicalData[historicalData.length - 1]?.timestamp
    }
  });
}));

// GET /api/prices/bulk-historical
router.get('/bulk-historical', catchAsync(async (req, res) => {
  const { symbols, timeframe = 'H1', limit = 1000 } = req.query;

  if (!symbols) {
    return res.status(400).json({
      status: 'error',
      message: 'Symbols parameter is required (comma-separated)'
    });
  }

  const symbolList = symbols.split(',').map(s => s.trim().toUpperCase());
  const results = {};

  for (const symbol of symbolList) {
    try {
      const data = await getHistoricalData(symbol, timeframe, parseInt(limit));
      results[symbol] = {
        status: 'success',
        data,
        count: data.length
      };
    } catch (error) {
      logger.error(`Error fetching historical data for ${symbol}:`, error);
      results[symbol] = {
        status: 'error',
        message: error.message,
        count: 0
      };
    }
  }

  res.json({
    status: 'success',
    data: results,
    timeframe,
    requestedLimit: parseInt(limit),
    symbols: symbolList
  });
}));

// GET /api/prices/stats
router.get('/stats', catchAsync(async (req, res) => {
  const stats = getPriceUpdateStats();

  res.json({
    status: 'success',
    data: stats
  });
}));

// POST /api/prices/subscribe
router.post('/subscribe', catchAsync(async (req, res) => {
  const { symbols } = req.body;

  if (!Array.isArray(symbols) || symbols.length === 0) {
    return res.status(400).json({
      status: 'error',
      message: 'Symbols array is required and cannot be empty'
    });
  }

  const validSymbols = symbols.map(s => s.toUpperCase());

  res.json({
    status: 'success',
    message: `Subscribed to ${validSymbols.length} symbols`,
    data: {
      symbols: validSymbols,
      timestamp: new Date().toISOString()
    }
  });
}));

// GET /api/prices/search
router.get('/search', catchAsync(async (req, res) => {
  const { q: query, limit = 50 } = req.query;

  if (!query) {
    return res.status(400).json({
      status: 'error',
      message: 'Search query parameter (q) is required'
    });
  }

  // This would typically search your database or external API
  // For now, we'll return a placeholder response
  res.json({
    status: 'success',
    data: [],
    query,
    count: 0,
    message: 'Search functionality not yet implemented'
  });
}));

// GET /api/prices/validate-candles/:symbol
router.get('/validate-candles/:symbol', catchAsync(async (req, res) => {
  const { symbol } = req.params;
  const { timeframe = 'H1', limit = 100 } = req.query;

  if (!symbol) {
    return res.status(400).json({
      status: 'error',
      message: 'Symbol parameter is required'
    });
  }

  try {
    // Get candles for validation
    const candles = await getHistoricalCandles(symbol.toUpperCase(), timeframe, parseInt(limit));

    if (candles.length === 0) {
      return res.status(404).json({
        status: 'error',
        message: `No candle data found for symbol: ${symbol}`
      });
    }

    // Validate the candles
    const validationResults = validateCandles(candles);

    res.json({
      status: 'success',
      data: validationResults,
      symbol: symbol.toUpperCase(),
      timeframe,
      count: candles.length,
      meta: {
        validationPassed: validationResults.valid === validationResults.total,
        validCandles: validationResults.valid,
        invalidCandles: validationResults.invalid,
        successRate: `${((validationResults.valid / validationResults.total) * 100).toFixed(2)}%`
      }
    });
  } catch (error) {
    logger.error(`Error validating candles for ${symbol}:`, error);
    res.status(500).json({
      status: 'error',
      message: 'Error validating candles',
      error: error.message
    });
  }
}));

// GET /api/prices/generate-test-candles/:symbol
router.get('/generate-test-candles/:symbol', catchAsync(async (req, res) => {
  const { symbol } = req.params;
  const { timeframe = 'H1', count = 100 } = req.query;

  if (!symbol) {
    return res.status(400).json({
      status: 'error',
      message: 'Symbol parameter is required'
    });
  }

  try {
    const testCandles = generateTestCandles(symbol.toUpperCase(), timeframe, parseInt(count));

    // Validate the generated test candles
    const validationResults = validateCandles(testCandles);

    res.json({
      status: 'success',
      data: testCandles,
      validation: validationResults,
      symbol: symbol.toUpperCase(),
      timeframe,
      count: testCandles.length,
      meta: {
        description: 'Test candles generated with realistic price movements for validation purposes',
        validationPassed: validationResults.valid === validationResults.total,
        successRate: `${((validationResults.valid / validationResults.total) * 100).toFixed(2)}%`
      }
    });
  } catch (error) {
    logger.error(`Error generating test candles for ${symbol}:`, error);
    res.status(500).json({
      status: 'error',
      message: 'Error generating test candles',
      error: error.message
    });
  }
}));

// GET /api/prices/candle-info/:symbol
router.get('/candle-info/:symbol', catchAsync(async (req, res) => {
  const { symbol } = req.params;
  const { timeframe = 'H1' } = req.query;

  if (!symbol) {
    return res.status(400).json({
      status: 'error',
      message: 'Symbol parameter is required'
    });
  }

  try {
    const candles = await getHistoricalCandles(symbol.toUpperCase(), timeframe, 1000);

    if (candles.length === 0) {
      return res.status(404).json({
        status: 'error',
        message: `No candle data found for symbol: ${symbol}`
      });
    }

    // Calculate statistics
    const closes = candles.map(c => parseFloat(c.close));
    const highs = candles.map(c => parseFloat(c.high));
    const lows = candles.map(c => parseFloat(c.low));
    const volumes = candles.map(c => parseInt(c.volume));

    const stats = {
      count: candles.length,
      priceRange: {
        min: Math.min(...closes),
        max: Math.max(...closes),
        avg: closes.reduce((a, b) => a + b, 0) / closes.length
      },
      highLowRange: {
        overallHigh: Math.max(...highs),
        overallLow: Math.min(...lows)
      },
      volume: {
        total: volumes.reduce((a, b) => a + b, 0),
        avg: volumes.reduce((a, b) => a + b, 0) / volumes.length,
        max: Math.max(...volumes),
        min: Math.min(...volumes)
      },
      timeframe,
      symbol: symbol.toUpperCase(),
      lastUpdated: candles[candles.length - 1]?.timestamp
    };

    res.json({
      status: 'success',
      data: stats
    });
  } catch (error) {
    logger.error(`Error getting candle info for ${symbol}:`, error);
    res.status(500).json({
      status: 'error',
      message: 'Error getting candle information',
      error: error.message
    });
  }
}));

module.exports = router;