/*
 * Distribution Tab Component for Enterprise Dashboard
 * Shows network-wide distribution status, route optimization, and delivery monitoring
 */

import React, { useEffect, useState } from 'react';
import { Card, CardContent, CardHeader, CardTitle } from '../ui/Card';
import { Button } from '../ui/Button';
import { Truck, AlertTriangle, CheckCircle2, Activity, Timer, Map, Route, Package, Clock, Bell, Calendar } from 'lucide-react';
import { useTranslation } from 'react-i18next';
import { useDistributionOverview } from '../../api/hooks/useEnterpriseDashboard';
import { useSSEEvents } from '../../hooks/useSSE';
import StatusCard from '../ui/StatusCard/StatusCard';
import { useTenantCurrency } from '../../hooks/useTenantCurrency';

interface DistributionTabProps {
  tenantId: string;
  selectedDate: string;
  onDateChange: (date: string) => void;
}

const DistributionTab: React.FC<DistributionTabProps> = ({ tenantId, selectedDate, onDateChange }) => {
  const { t } = useTranslation('dashboard');
  const { currencySymbol } = useTenantCurrency();
  
  // Get distribution data
  const {
    data: distributionOverview,
    isLoading: isDistributionLoading,
    error: distributionError
  } = useDistributionOverview(tenantId, selectedDate, {
    refetchInterval: 60000, // Refetch every minute
    enabled: !!tenantId,
  });

  // Real-time SSE events
  const { events: sseEvents, isConnected: sseConnected } = useSSEEvents({ 
    channels: ['*.alerts', '*.notifications', 'recommendations'] 
  });

  // State for real-time delivery status
  const [deliveryStatus, setDeliveryStatus] = useState({
    total: 0,
    onTime: 0,
    delayed: 0,
    inTransit: 0,
    completed: 0
  });

  // State for route optimization metrics
  const [optimizationMetrics, setOptimizationMetrics] = useState({
    distanceSaved: 0,
    timeSaved: 0,
    fuelSaved: 0,
    co2Saved: 0
  });

  // State for real-time events
  const [recentDeliveryEvents, setRecentDeliveryEvents] = useState<any[]>([]);

  // Process SSE events for distribution updates
  useEffect(() => {
    if (sseEvents.length === 0) return;

    // Filter delivery and distribution-related events
    const deliveryEvents = sseEvents.filter(event => 
      event.event_type.includes('delivery_') || 
      event.event_type.includes('route_') ||
      event.event_type.includes('shipment_') ||
      event.entity_type === 'delivery' ||
      event.entity_type === 'shipment'
    );

    if (deliveryEvents.length === 0) return;

    // Update delivery status based on events
    let newStatus = { ...deliveryStatus };
    let newMetrics = { ...optimizationMetrics };

    deliveryEvents.forEach(event => {
      switch (event.event_type) {
        case 'delivery_completed':
          newStatus.completed += 1;
          newStatus.inTransit = Math.max(0, newStatus.inTransit - 1);
          break;
        case 'delivery_started':
        case 'delivery_in_transit':
          newStatus.inTransit += 1;
          break;
        case 'delivery_delayed':
          newStatus.delayed += 1;
          break;
        case 'route_optimized':
          if (event.event_metadata?.distance_saved) {
            newMetrics.distanceSaved += event.event_metadata.distance_saved;
          }
          if (event.event_metadata?.time_saved) {
            newMetrics.timeSaved += event.event_metadata.time_saved;
          }
          if (event.event_metadata?.fuel_saved) {
            newMetrics.fuelSaved += event.event_metadata.fuel_saved;
          }
          break;
      }
    });

    setDeliveryStatus(newStatus);
    setOptimizationMetrics(newMetrics);
    setRecentDeliveryEvents(deliveryEvents.slice(0, 5));
  }, [sseEvents]);

  // Initialize status from API data
  useEffect(() => {
    if (distributionOverview) {
      const statusCounts = distributionOverview.status_counts || {};
      setDeliveryStatus({
        total: Object.values(statusCounts).reduce((sum, count) => sum + count, 0),
        onTime: statusCounts['delivered'] || 0,
        delayed: statusCounts['overdue'] || 0,
        inTransit: (statusCounts['in_transit'] || 0) + (statusCounts['pending'] || 0),
        completed: statusCounts['delivered'] || 0
      });
    }
  }, [distributionOverview]);

  const isLoading = isDistributionLoading;

  // Mock route data - in Phase 2 this will come from real API
  const mockRoutes = [
    {
      id: 'route-1',
      name: 'Madrid → Barcelona',
      status: 'in_transit',
      distance: '620 km',
      duration: '6h 30m',
      stops: 3,
      optimizationSavings: '12 km (1.9%)',
      vehicles: ['TRUCK-001', 'TRUCK-002']
    },
    {
      id: 'route-2',
      name: 'Barcelona → Valencia',
      status: 'completed',
      distance: '350 km',
      duration: '4h 15m',
      stops: 2,
      optimizationSavings: '8 km (2.3%)',
      vehicles: ['VAN-005']
    },
    {
      id: 'route-3',
      name: 'Central → Outlets (Daily)',
      status: 'pending',
      distance: '180 km',
      duration: '3h 00m',
      stops: 5,
      optimizationSavings: '25 km (13.9%)',
      vehicles: ['TRUCK-003', 'VAN-006', 'VAN-007']
    }
  ];

  return (
    <div className="space-y-8">
      {/* Distribution Summary */}
      <div className="mb-8">
        <h2 className="text-2xl font-bold text-[var(--text-primary)] mb-4 flex items-center gap-2">
          <Truck className="w-6 h-6 text-[var(--color-primary)]" />
          {t('enterprise.distribution_summary')}
        </h2>
        
        {/* Date selector */}
        <div className="mb-4 flex items-center gap-4">
          <div className="flex items-center gap-2">
            <Calendar className="w-5 h-5 text-[var(--text-secondary)]" />
            <input
              type="date"
              value={selectedDate}
              onChange={(e) => onDateChange(e.target.value)}
              className="border border-[var(--border-primary)] rounded-md px-3 py-2 text-sm bg-[var(--input-bg)] text-[var(--text-primary)]"
            />
          </div>
          {sseConnected && (
            <div className="flex items-center gap-1 text-xs text-[var(--color-success)]">
              <span className="w-2 h-2 rounded-full bg-[var(--color-success)] animate-pulse"></span>
              {t('enterprise.live_updates')}
            </div>
          )}
        </div>

        <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-4 gap-6">
          {/* Total Deliveries */}
          <Card>
            <CardHeader className="flex flex-row items-center justify-between pb-2">
              <CardTitle className="text-sm font-medium text-[var(--text-secondary)]">
                {t('enterprise.total_deliveries')}
              </CardTitle>
              <Package className="w-5 h-5 text-[var(--color-primary)]" />
            </CardHeader>
            <CardContent>
              <div className="text-3xl font-bold text-[var(--text-primary)]">
                {deliveryStatus.total}
              </div>
              <p className="text-xs text-[var(--text-secondary)] mt-1">
                {t('enterprise.all_shipments')}
              </p>
            </CardContent>
          </Card>

          {/* On-time Deliveries */}
          <Card>
            <CardHeader className="flex flex-row items-center justify-between pb-2">
              <CardTitle className="text-sm font-medium text-[var(--text-secondary)]">
                {t('enterprise.on_time_deliveries')}
              </CardTitle>
              <CheckCircle2 className="w-5 h-5 text-[var(--color-success)]" />
            </CardHeader>
            <CardContent>
              <div className="text-3xl font-bold text-[var(--color-success)]">
                {deliveryStatus.onTime}
              </div>
              <p className="text-xs text-[var(--text-secondary)] mt-1">
                {deliveryStatus.total > 0 
                  ? `${Math.round((deliveryStatus.onTime / deliveryStatus.total) * 100)}% ${t('enterprise.on_time_rate')}`
                  : t('enterprise.no_deliveries')}
              </p>
            </CardContent>
          </Card>

          {/* Delayed Deliveries */}
          <Card>
            <CardHeader className="flex flex-row items-center justify-between pb-2">
              <CardTitle className="text-sm font-medium text-[var(--text-secondary)]">
                {t('enterprise.delayed_deliveries')}
              </CardTitle>
              <AlertTriangle className="w-5 h-5 text-[var(--color-warning)]" />
            </CardHeader>
            <CardContent>
              <div className="text-3xl font-bold text-[var(--color-warning)]">
                {deliveryStatus.delayed}
              </div>
              <p className="text-xs text-[var(--text-secondary)] mt-1">
                {deliveryStatus.total > 0
                  ? `${Math.round((deliveryStatus.delayed / deliveryStatus.total) * 100)}% ${t('enterprise.delay_rate')}`
                  : t('enterprise.no_delays')}
              </p>
            </CardContent>
          </Card>

          {/* In Transit */}
          <Card>
            <CardHeader className="flex flex-row items-center justify-between pb-2">
              <CardTitle className="text-sm font-medium text-[var(--text-secondary)]">
                {t('enterprise.in_transit')}
              </CardTitle>
              <Activity className="w-5 h-5 text-[var(--color-info)]" />
            </CardHeader>
            <CardContent>
              <div className="text-3xl font-bold text-[var(--color-info)]">
                {deliveryStatus.inTransit}
              </div>
              <p className="text-xs text-[var(--text-secondary)] mt-1">
                {t('enterprise.currently_en_route')}
              </p>
            </CardContent>
          </Card>
        </div>
      </div>

      {/* Route Optimization Metrics */}
      <div className="mb-8">
        <h2 className="text-2xl font-bold text-[var(--text-primary)] mb-4 flex items-center gap-2">
          <Route className="w-6 h-6 text-[var(--color-success)]" />
          {t('enterprise.route_optimization')}
        </h2>
        <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-4 gap-6">
          {/* Distance Saved */}
          <Card>
            <CardHeader className="flex flex-row items-center justify-between pb-2">
              <CardTitle className="text-sm font-medium text-[var(--text-secondary)]">
                {t('enterprise.distance_saved')}
              </CardTitle>
              <Map className="w-5 h-5 text-[var(--color-success)]" />
            </CardHeader>
            <CardContent>
              <div className="text-3xl font-bold text-[var(--color-success)]">
                {optimizationMetrics.distanceSaved} km
              </div>
              <p className="text-xs text-[var(--text-secondary)] mt-1">
                {t('enterprise.total_distance_saved')}
              </p>
            </CardContent>
          </Card>

          {/* Time Saved */}
          <Card>
            <CardHeader className="flex flex-row items-center justify-between pb-2">
              <CardTitle className="text-sm font-medium text-[var(--text-secondary)]">
                {t('enterprise.time_saved')}
              </CardTitle>
              <Timer className="w-5 h-5 text-[var(--color-primary)]" />
            </CardHeader>
            <CardContent>
              <div className="text-3xl font-bold text-[var(--color-primary)]">
                {optimizationMetrics.timeSaved} min
              </div>
              <p className="text-xs text-[var(--text-secondary)] mt-1">
                {t('enterprise.total_time_saved')}
              </p>
            </CardContent>
          </Card>

          {/* Fuel Saved */}
          <Card>
            <CardHeader className="flex flex-row items-center justify-between pb-2">
              <CardTitle className="text-sm font-medium text-[var(--text-secondary)]">
                {t('enterprise.fuel_saved')}
              </CardTitle>
              <Package className="w-5 h-5 text-[var(--color-info)]" />
            </CardHeader>
            <CardContent>
              <div className="text-3xl font-bold text-[var(--color-info)]">
                {currencySymbol}{optimizationMetrics.fuelSaved.toFixed(2)}
              </div>
              <p className="text-xs text-[var(--text-secondary)] mt-1">
                {t('enterprise.estimated_fuel_savings')}
              </p>
            </CardContent>
          </Card>

          {/* CO2 Saved */}
          <Card>
            <CardHeader className="flex flex-row items-center justify-between pb-2">
              <CardTitle className="text-sm font-medium text-[var(--text-secondary)]">
                {t('enterprise.co2_saved')}
              </CardTitle>
              <CheckCircle2 className="w-5 h-5 text-[var(--color-success)]" />
            </CardHeader>
            <CardContent>
              <div className="text-3xl font-bold text-[var(--color-success)]">
                {optimizationMetrics.co2Saved} kg
              </div>
              <p className="text-xs text-[var(--text-secondary)] mt-1">
                {t('enterprise.estimated_co2_reduction')}
              </p>
            </CardContent>
          </Card>
        </div>
      </div>

      {/* Active Routes */}
      <div className="mb-8">
        <h2 className="text-2xl font-bold text-[var(--text-primary)] mb-4 flex items-center gap-2">
          <Route className="w-6 h-6 text-[var(--color-primary)]" />
          {t('enterprise.active_routes')}
        </h2>
        <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-3 gap-6">
          {mockRoutes.map((route) => {
            // Determine status configuration
            const getStatusConfig = () => {
              switch (route.status) {
                case 'completed':
                  return {
                    color: '#10b981', // emerald-500
                    text: t('enterprise.route_completed'),
                    icon: CheckCircle2
                  };
                case 'delayed':
                case 'overdue':
                  return {
                    color: '#ef4444', // red-500
                    text: t('enterprise.route_delayed'),
                    icon: AlertTriangle,
                    isCritical: true
                  };
                case 'in_transit':
                  return {
                    color: '#3b82f6', // blue-500
                    text: t('enterprise.route_in_transit'),
                    icon: Activity,
                    isHighlight: true
                  };
                default: // pending, planned
                  return {
                    color: '#f59e0b', // amber-500
                    text: t('enterprise.route_pending'),
                    icon: Clock
                  };
              }
            };

            const statusConfig = getStatusConfig();

            return (
              <StatusCard
                key={route.id}
                id={route.id}
                statusIndicator={statusConfig}
                title={route.name}
                subtitle={`${t('enterprise.distance')}: ${route.distance}`}
                primaryValue={route.duration}
                primaryValueLabel={t('enterprise.estimated_duration')}
                secondaryInfo={{
                  label: t('enterprise.stops'),
                  value: `${route.stops}`
                }}
                progress={{
                  label: t('enterprise.optimization'),
                  percentage: route.status === 'completed' ? 100 : 
                             route.status === 'in_transit' ? 75 : 
                             route.status === 'delayed' ? 50 : 25,
                  color: statusConfig.color
                }}
                metadata={[
                  `${t('enterprise.optimization_savings')}: ${route.optimizationSavings}`,
                  `${t('enterprise.vehicles')}: ${route.vehicles.join(', ')}`
                ]}
                actions={[
                  {
                    label: t('enterprise.track_route'),
                    icon: Map,
                    variant: 'outline',
                    onClick: () => {
                      // In Phase 2, this will navigate to route tracking page
                      console.log(`Track route ${route.name}`);
                    },
                    priority: 'primary'
                  }
                ]}
                onClick={() => {
                  // In Phase 2, this will navigate to route detail page
                  console.log(`View route ${route.name}`);
                }}
              />
            );
          })}
        </div>
      </div>

      {/* Real-time Delivery Events */}
      <div className="mb-8">
        <h2 className="text-2xl font-bold text-[var(--text-primary)] mb-4 flex items-center gap-2">
          <Bell className="w-6 h-6 text-[var(--color-info)]" />
          {t('enterprise.real_time_delivery_events')}
        </h2>
        <Card>
          <CardHeader className="flex flex-row items-center justify-between pb-2">
            <div className="flex items-center gap-2">
              <CardTitle className="text-sm font-medium text-[var(--text-secondary)]">
                {t('enterprise.recent_delivery_activity')}
              </CardTitle>
            </div>
          </CardHeader>
          <CardContent>
            {recentDeliveryEvents.length > 0 ? (
              <div className="space-y-4">
                {recentDeliveryEvents.map((event, index) => {
                  // Determine event icon and color based on type
                  const getEventConfig = () => {
                    switch (event.event_type) {
                      case 'delivery_delayed':
                      case 'delivery_overdue':
                        return { icon: AlertTriangle, color: 'text-[var(--color-warning)]' };
                      case 'delivery_completed':
                      case 'delivery_received':
                        return { icon: CheckCircle2, color: 'text-[var(--color-success)]' };
                      case 'delivery_started':
                      case 'delivery_in_transit':
                        return { icon: Activity, color: 'text-[var(--color-info)]' };
                      case 'route_optimized':
                        return { icon: Route, color: 'text-[var(--color-primary)]' };
                      default:
                        return { icon: Bell, color: 'text-[var(--color-secondary)]' };
                    }
                  };

                  const { icon: EventIcon, color } = getEventConfig();
                  const eventTime = new Date(event.timestamp || event.created_at || Date.now());

                  return (
                    <div key={index} className="flex items-start gap-3 p-3 rounded-lg border border-[var(--border-primary)]">
                      <div className={`p-2 rounded-lg ${color.replace('text', 'bg')}`}>
                        <EventIcon className={`w-5 h-5 ${color}`} />
                      </div>
                      <div className="flex-1 min-w-0">
                        <div className="flex items-center justify-between gap-2">
                          <p className="font-medium text-[var(--text-primary)]">
                            {event.event_type.replace(/_/g, ' ')}
                          </p>
                          <p className="text-xs text-[var(--text-tertiary)] whitespace-nowrap">
                            {eventTime.toLocaleTimeString()}
                          </p>
                        </div>
                        {event.message && (
                          <p className="text-sm text-[var(--text-secondary)] mt-1">
                            {event.message}
                          </p>
                        )}
                        {event.entity_type && event.entity_id && (
                          <p className="text-xs text-[var(--text-tertiary)] mt-1">
                            {event.entity_type}: {event.entity_id}
                          </p>
                        )}
                        {event.event_metadata?.route_name && (
                          <p className="text-xs text-[var(--text-tertiary)] mt-1">
                            {t('enterprise.route')}: {event.event_metadata.route_name}
                          </p>
                        )}
                      </div>
                    </div>
                  );
                })}
              </div>
            ) : (
              <div className="text-center py-8 text-[var(--text-secondary)]">
                {sseConnected ? t('enterprise.no_recent_delivery_activity') : t('enterprise.waiting_for_updates')}
              </div>
            )}
          </CardContent>
        </Card>
      </div>

      {/* Quick Actions */}
      <div className="mb-8">
        <h2 className="text-2xl font-bold text-[var(--text-primary)] mb-4 flex items-center gap-2">
          <Timer className="w-6 h-6 text-[var(--color-info)]" />
          {t('enterprise.quick_actions')}
        </h2>
        <div className="grid grid-cols-1 sm:grid-cols-2 lg:grid-cols-3 gap-6">
          <Card>
            <CardContent className="p-6">
              <div className="flex items-center gap-3 mb-4">
                <Route className="w-6 h-6 text-[var(--color-primary)]" />
                <h3 className="text-lg font-semibold text-[var(--text-primary)]">{t('enterprise.optimize_routes')}</h3>
              </div>
              <p className="text-[var(--text-secondary)] mb-4">{t('enterprise.optimize_routes_description')}</p>
              <Button
                onClick={() => window.location.href = `/app/tenants/${tenantId}/distribution/routes/optimize`}
                className="w-full"
              >
                {t('enterprise.run_optimization')}
              </Button>
            </CardContent>
          </Card>

          <Card>
            <CardContent className="p-6">
              <div className="flex items-center gap-3 mb-4">
                <Truck className="w-6 h-6 text-[var(--color-success)]" />
                <h3 className="text-lg font-semibold text-[var(--text-primary)]">{t('enterprise.manage_vehicles')}</h3>
              </div>
              <p className="text-[var(--text-secondary)] mb-4">{t('enterprise.manage_vehicle_fleet')}</p>
              <Button
                onClick={() => window.location.href = `/app/tenants/${tenantId}/distribution/vehicles`}
                variant="outline"
                className="w-full"
              >
                {t('enterprise.view_vehicles')}
              </Button>
            </CardContent>
          </Card>

          <Card>
            <CardContent className="p-6">
              <div className="flex items-center gap-3 mb-4">
                <Map className="w-6 h-6 text-[var(--color-info)]" />
                <h3 className="text-lg font-semibold text-[var(--text-primary)]">{t('enterprise.live_tracking')}</h3>
              </div>
              <p className="text-[var(--text-secondary)] mb-4">{t('enterprise.real_time_gps_tracking')}</p>
              <Button
                onClick={() => window.location.href = `/app/tenants/${tenantId}/distribution/tracking`}
                variant="outline"
                className="w-full"
              >
                {t('enterprise.open_tracking_map')}
              </Button>
            </CardContent>
          </Card>
        </div>
      </div>
    </div>
  );
};

export default DistributionTab;