const { outputProgress, formatElapsedTime, estimateRemaining, calculateRate, logError } = require('./utils/progress');
const { getConnection } = require('./utils/db');

async function calculateFinancialMetrics(startTime, totalProducts, processedCount = 0, isCancelled = false) {
    const connection = await getConnection();
    let success = false;
    let processedOrders = 0;
    
    try {
        if (isCancelled) {
            outputProgress({
                status: 'cancelled',
                operation: 'Financial metrics calculation cancelled',
                current: processedCount,
                total: totalProducts,
                elapsed: formatElapsedTime(startTime),
                remaining: null,
                rate: calculateRate(startTime, processedCount),
                percentage: ((processedCount / totalProducts) * 100).toFixed(1),
                timing: {
                    start_time: new Date(startTime).toISOString(),
                    end_time: new Date().toISOString(),
                    elapsed_seconds: Math.round((Date.now() - startTime) / 1000)
                }
            });
            return {
                processedProducts: processedCount,
                processedOrders: 0,
                processedPurchaseOrders: 0,
                success
            };
        }

        // Get order count that will be processed
        const orderCount = await connection.query(`
            SELECT COUNT(*) as count 
            FROM orders o 
            WHERE o.canceled = false
                AND DATE(o.date) >= CURRENT_DATE - INTERVAL '12 months'
        `);
        processedOrders = parseInt(orderCount.rows[0].count);

        outputProgress({
            status: 'running',
            operation: 'Starting financial metrics calculation',
            current: processedCount,
            total: totalProducts,
            elapsed: formatElapsedTime(startTime),
            remaining: estimateRemaining(startTime, processedCount, totalProducts),
            rate: calculateRate(startTime, processedCount),
            percentage: ((processedCount / totalProducts) * 100).toFixed(1),
            timing: {
                start_time: new Date(startTime).toISOString(),
                end_time: new Date().toISOString(),
                elapsed_seconds: Math.round((Date.now() - startTime) / 1000)
            }
        });

        // Calculate financial metrics with optimized query
        await connection.query(`
            WITH product_financials AS (
                SELECT 
                    p.pid,
                    p.cost_price * p.stock_quantity as inventory_value,
                    SUM(o.quantity * o.price) as total_revenue,
                    SUM(o.quantity * p.cost_price) as cost_of_goods_sold,
                    SUM(o.quantity * (o.price - p.cost_price)) as gross_profit,
                    MIN(o.date) as first_sale_date,
                    MAX(o.date) as last_sale_date,
                    EXTRACT(DAY FROM (MAX(o.date)::timestamp with time zone - MIN(o.date)::timestamp with time zone)) + 1 as calculation_period_days,
                    COUNT(DISTINCT DATE(o.date)) as active_days
                FROM products p
                LEFT JOIN orders o ON p.pid = o.pid
                WHERE o.canceled = false
                    AND DATE(o.date) >= CURRENT_DATE - INTERVAL '12 months'
                GROUP BY p.pid, p.cost_price, p.stock_quantity
            )
            UPDATE product_metrics pm
            SET 
                inventory_value = COALESCE(pf.inventory_value, 0),
                total_revenue = COALESCE(pf.total_revenue, 0),
                cost_of_goods_sold = COALESCE(pf.cost_of_goods_sold, 0),
                gross_profit = COALESCE(pf.gross_profit, 0),
                gmroi = CASE 
                    WHEN COALESCE(pf.inventory_value, 0) > 0 AND pf.active_days > 0 THEN 
                        (COALESCE(pf.gross_profit, 0) * (365.0 / pf.active_days)) / COALESCE(pf.inventory_value, 0)
                    ELSE 0 
                END,
                last_calculated_at = CURRENT_TIMESTAMP
            FROM product_financials pf
            WHERE pm.pid = pf.pid
        `);

        processedCount = Math.floor(totalProducts * 0.65);
        outputProgress({
            status: 'running',
            operation: 'Base financial metrics calculated, updating time aggregates',
            current: processedCount,
            total: totalProducts,
            elapsed: formatElapsedTime(startTime),
            remaining: estimateRemaining(startTime, processedCount, totalProducts),
            rate: calculateRate(startTime, processedCount),
            percentage: ((processedCount / totalProducts) * 100).toFixed(1),
            timing: {
                start_time: new Date(startTime).toISOString(),
                end_time: new Date().toISOString(),
                elapsed_seconds: Math.round((Date.now() - startTime) / 1000)
            }
        });

        if (isCancelled) return {
            processedProducts: processedCount,
            processedOrders,
            processedPurchaseOrders: 0,
            success
        };

        // Update time-based aggregates with optimized query
        await connection.query(`
            WITH monthly_financials AS (
                SELECT 
                    p.pid,
                    EXTRACT(YEAR FROM o.date::timestamp with time zone) as year,
                    EXTRACT(MONTH FROM o.date::timestamp with time zone) as month,
                    p.cost_price * p.stock_quantity as inventory_value,
                    SUM(o.quantity * (o.price - p.cost_price)) as gross_profit,
                    COUNT(DISTINCT DATE(o.date)) as active_days,
                    MIN(o.date) as period_start,
                    MAX(o.date) as period_end
                FROM products p
                LEFT JOIN orders o ON p.pid = o.pid
                WHERE o.canceled = false
                GROUP BY p.pid, EXTRACT(YEAR FROM o.date::timestamp with time zone), EXTRACT(MONTH FROM o.date::timestamp with time zone), p.cost_price, p.stock_quantity
            )
            UPDATE product_time_aggregates pta
            SET 
                inventory_value = COALESCE(mf.inventory_value, 0),
                gmroi = CASE 
                    WHEN COALESCE(mf.inventory_value, 0) > 0 AND mf.active_days > 0 THEN 
                        (COALESCE(mf.gross_profit, 0) * (365.0 / mf.active_days)) / COALESCE(mf.inventory_value, 0)
                    ELSE 0 
                END
            FROM monthly_financials mf
            WHERE pta.pid = mf.pid 
                AND pta.year = mf.year 
                AND pta.month = mf.month
        `);

        processedCount = Math.floor(totalProducts * 0.70);
        outputProgress({
            status: 'running',
            operation: 'Time-based aggregates updated',
            current: processedCount,
            total: totalProducts,
            elapsed: formatElapsedTime(startTime),
            remaining: estimateRemaining(startTime, processedCount, totalProducts),
            rate: calculateRate(startTime, processedCount),
            percentage: ((processedCount / totalProducts) * 100).toFixed(1),
            timing: {
                start_time: new Date(startTime).toISOString(),
                end_time: new Date().toISOString(),
                elapsed_seconds: Math.round((Date.now() - startTime) / 1000)
            }
        });

        // If we get here, everything completed successfully
        success = true;
        
        // Update calculate_status
        await connection.query(`
            INSERT INTO calculate_status (module_name, last_calculation_timestamp)
            VALUES ('financial_metrics', NOW())
            ON CONFLICT (module_name) DO UPDATE
            SET last_calculation_timestamp = NOW()
        `);

        return {
            processedProducts: processedCount,
            processedOrders,
            processedPurchaseOrders: 0,
            success
        };

    } catch (error) {
        success = false;
        logError(error, 'Error calculating financial metrics');
        throw error;
    } finally {
        if (connection) {
            connection.release();
        }
    }
}

module.exports = calculateFinancialMetrics;