"use client";

import React, { useEffect, useRef, useState } from 'react';
import mapboxgl from 'mapbox-gl';
import 'mapbox-gl/dist/mapbox-gl.css';
import MapboxGeocoder from '@mapbox/mapbox-gl-geocoder';
import '@mapbox/mapbox-gl-geocoder/dist/mapbox-gl-geocoder.css';
import { generateDCPoints, haversine, PointFeature, convertCrashDataToGeoJSON } from '../lib/mapUtils';
import { useCrashData } from '../hooks/useCrashData';
import { CrashData } from '../api/crashes/route';

export type PopupData = { 
	lngLat: [number, number]; 
	mag?: number; 
	text?: string; 
	crashData?: CrashData;
	stats?: { 
		count: number; 
		avg?: number; 
		min?: number; 
		max?: number; 
		radiusMeters?: number;
		severityCounts?: {
			fatal: number;
			majorInjury: number;
			minorInjury: number;
			propertyOnly: number;
		};
		crashes?: any[]; // Top 5 nearby crashes
	} 
} | null;

interface MapViewProps {
	mapStyleChoice: 'dark' | 'streets';
	heatRadius: number;
	heatIntensity: number;
	heatVisible: boolean;
	pointsVisible: boolean;
	onMapReady?: (map: mapboxgl.Map) => void;
	onPopupCreate?: (p: PopupData) => void; // fires when user clicks features and we want to show popup
	onGeocoderResult?: (lngLat: [number, number]) => void;
	useRealCrashData?: boolean; // whether to use real crash data or synthetic data
	crashData?: CrashData[]; // external crash data to use
}

export default function MapView({ 
	mapStyleChoice, 
	heatRadius, 
	heatIntensity, 
	heatVisible, 
	pointsVisible, 
	onMapReady, 
	onPopupCreate, 
	onGeocoderResult, 
	useRealCrashData = true,
	crashData = []
}: MapViewProps) {
	const containerRef = useRef<HTMLDivElement | null>(null);
	const mapContainerRef = useRef<HTMLDivElement | null>(null);
	const mapRef = useRef<mapboxgl.Map | null>(null);
	const styleChoiceRef = useRef<'dark' | 'streets'>(mapStyleChoice);
	const [size, setSize] = useState({ width: 0, height: 0 });
	const dcDataRef = useRef<GeoJSON.FeatureCollection | null>(null);
	const crashDataHook = useCrashData({ autoLoad: false, limit: 10000 }); // Don't auto-load if external data provided

	// Update map data when crash data is loaded
	useEffect(() => {
		const activeData = crashData.length > 0 ? crashData : crashDataHook.data;
		console.log('MapView useEffect: crashData.length =', crashData.length, 'crashDataHook.data.length =', crashDataHook.data.length);
		if (useRealCrashData && activeData.length > 0) {
			console.log('Converting crash data to GeoJSON...');
			dcDataRef.current = convertCrashDataToGeoJSON(activeData);
			// Update the map source if map is ready
			const map = mapRef.current;
			if (map && map.isStyleLoaded()) {
				console.log('Updating map source with new data...');
				if (map.getSource('dc-quakes')) {
					(map.getSource('dc-quakes') as mapboxgl.GeoJSONSource).setData(dcDataRef.current);
				} else {
					console.log('Source not found, calling addDataAndLayers');
					// Call the inner function manually - we need to recreate it here
					if (dcDataRef.current) {
						console.log('Adding data and layers, data has', dcDataRef.current.features.length, 'features');
						if (!map.getSource('dc-quakes')) {
							console.log('Creating new source');
							map.addSource('dc-quakes', { type: 'geojson', data: dcDataRef.current });
						}
						// Add layers if they don't exist
						if (!map.getLayer('dc-heat')) {
							map.addLayer({
								id: 'dc-heat', type: 'heatmap', source: 'dc-quakes', maxzoom: 15,
								paint: {
									'heatmap-weight': ['interpolate', ['linear'], ['get', 'mag'], 0, 0, 6, 1],
									'heatmap-intensity': heatIntensity,
									'heatmap-color': [
										'interpolate', 
										['linear'], 
										['heatmap-density'], 
										0, 'rgba(0,0,0,0)', 
										0.2, 'rgba(255,255,0,0.7)', 
										0.4, 'rgba(255,165,0,0.8)', 
										0.6, 'rgba(255,69,0,0.9)', 
										0.8, 'rgba(255,0,0,0.95)', 
										1, 'rgba(139,0,0,1)'
									],
									'heatmap-radius': heatRadius,
									'heatmap-opacity': ['interpolate', ['linear'], ['zoom'], 7, 1, 12, 0.8]
								}
							});
						}
						if (!map.getLayer('dc-point')) {
							map.addLayer({
								id: 'dc-point', type: 'circle', source: 'dc-quakes', minzoom: 12,
								paint: {
									'circle-radius': ['interpolate', ['linear'], ['get', 'mag'], 1, 3, 6, 10],
									'circle-color': [
										'interpolate', 
										['linear'], 
										['get', 'mag'], 
										1, styleChoiceRef.current === 'dark' ? '#ffff99' : '#ffa500',
										3, styleChoiceRef.current === 'dark' ? '#ff6666' : '#ff4500',
										6, styleChoiceRef.current === 'dark' ? '#ff0000' : '#8b0000'
									] as any,
									'circle-opacity': ['interpolate', ['linear'], ['zoom'], 12, 0.7, 14, 0.9],
									'circle-stroke-width': 1,
									'circle-stroke-color': styleChoiceRef.current === 'dark' ? '#ffffff' : '#000000'
								}
							});
						}
						// Update layer visibility
						if (map.getLayer('dc-heat')) {
							map.setLayoutProperty('dc-heat', 'visibility', heatVisible ? 'visible' : 'none');
						}
						if (map.getLayer('dc-point')) {
							map.setLayoutProperty('dc-point', 'visibility', pointsVisible ? 'visible' : 'none');
						}
					}
				}
			} else {
				console.log('Map style not loaded yet');
			}
		}
	}, [useRealCrashData, crashDataHook.data, crashData, heatRadius, heatIntensity, heatVisible, pointsVisible]);

	useEffect(() => {
		const el = containerRef.current;
		if (!el) return;

		setSize({ width: el.clientWidth, height: el.clientHeight });

		const ro = new ResizeObserver((entries) => {
			for (const entry of entries) {
				const cr = entry.contentRect;
				setSize({ width: Math.round(cr.width), height: Math.round(cr.height) });
			}
		});

		ro.observe(el);
		return () => ro.disconnect();
	}, []);

	// react to style choice changes
	useEffect(() => {
		const map = mapRef.current;
		if (!map) return;
		const styleUrl = mapStyleChoice === 'dark' ? 'mapbox://styles/mapbox/dark-v10' : 'mapbox://styles/mapbox/streets-v11';
		try {
			map.setStyle(styleUrl);
		} catch (e) {
			// some map versions may throw; still listen for styledata to re-add layers
		}
		// update the styleChoiceRef so newly-created layers pick up correct color
		styleChoiceRef.current = mapStyleChoice;
		// if the dc-point layer exists, update its circle-color to match the style
		if (map.getLayer && map.getLayer('dc-point')) {
			const colorExpression = [
				'interpolate', 
				['linear'], 
				['get', 'mag'], 
				1, mapStyleChoice === 'dark' ? '#ffff99' : '#ffa500',
				3, mapStyleChoice === 'dark' ? '#ff6666' : '#ff4500',
				6, mapStyleChoice === 'dark' ? '#ff0000' : '#8b0000'
			] as any;
			const strokeColor = mapStyleChoice === 'dark' ? '#ffffff' : '#000000';
			try { 
				map.setPaintProperty('dc-point', 'circle-color', colorExpression);
				map.setPaintProperty('dc-point', 'circle-stroke-color', strokeColor);
			} catch (e) {}
		}
	}, [mapStyleChoice]);

	useEffect(() => {
		const mapEl = mapContainerRef.current;
		if (!mapEl) return;

		const token = process.env.NEXT_PUBLIC_MAPBOX_TOKEN || process.env.NEXT_PUBLIC_MAPBOX_TOKEN;
		if (!token) {
			console.warn('Missing NEXT_PUBLIC_MAPBOX_TOKEN environment variable. Mapbox map will not initialize correctly.');
		}
		mapboxgl.accessToken = token ?? '';

		const styleUrl = mapStyleChoice === 'dark'
			? 'mapbox://styles/mapbox/dark-v10'
			: 'mapbox://styles/mapbox/streets-v11';

		// bounding box roughly covering the DMV / Washington, DC area
		const dcBounds: [[number, number], [number, number]] = [
			[-77.25, 38.80], // southwest [lng, lat]
			[-76.90, 39.05]  // northeast [lng, lat]
		];

		mapRef.current = new mapboxgl.Map({ container: mapEl, style: styleUrl, center: [-77.0369, 38.9072], zoom: 11, maxBounds: dcBounds });
		const map = mapRef.current;

		// NOTE: geocoder control intentionally removed from map-level UI.
		// The sidebar provides embedded geocoder inputs; keeping both leads to duplicate controls.

		// Initialize data based on preference
		const activeData = crashData.length > 0 ? crashData : crashDataHook.data;
		console.log('Initializing map data, activeData length:', activeData.length);
		if (useRealCrashData && activeData.length > 0) {
			console.log('Using real crash data');
			dcDataRef.current = convertCrashDataToGeoJSON(activeData);
		} else if (!useRealCrashData) {
			console.log('Using synthetic data');
			dcDataRef.current = generateDCPoints(900);
		} else {
			console.log('No data available yet, using empty data');
			dcDataRef.current = { type: 'FeatureCollection' as const, features: [] };
		}

		const computeNearbyStats = async (center: [number, number], radiusMeters = 300) => {
			try {
				const [lng, lat] = center;
				const response = await fetch(`/api/crashes/nearby?lng=${lng}&lat=${lat}&radius=${radiusMeters}&limit=1000`);
				
				if (!response.ok) {
					console.warn('Failed to fetch nearby crash data:', response.status);
					return { count: 0 };
				}
				
				const data = await response.json();
				const crashes = data.data || [];
				
				// Filter out any null or invalid crash data on client side
				const validCrashes = crashes.filter((crash: any) => 
					crash && 
					crash.id && 
					typeof crash.latitude === 'number' && 
					typeof crash.longitude === 'number' &&
					!isNaN(crash.latitude) && 
					!isNaN(crash.longitude) &&
					crash.latitude !== 0 && 
					crash.longitude !== 0
				);
				
				if (validCrashes.length === 0) {
					return { count: 0, radiusMeters };
				}
				
				// Calculate severity statistics from MongoDB data
				const severityValues = validCrashes.map((crash: any) => {
					// Convert severity to numeric value for stats
					switch (crash.severity) {
						case 'Fatal': return 6;
						case 'Major Injury': return 4;
						case 'Minor Injury': return 2;
						case 'Property Damage Only': return 1;
						default: return 1;
					}
				});
				
				// Calculate statistics
				const sum = severityValues.reduce((s: number, x: number) => s + x, 0);
				const avg = +(sum / severityValues.length).toFixed(2);
				const min = Math.min(...severityValues);
				const max = Math.max(...severityValues);
				
				// Count by severity type
				const severityCounts = {
					fatal: validCrashes.filter((c: any) => c.severity === 'Fatal').length,
					majorInjury: validCrashes.filter((c: any) => c.severity === 'Major Injury').length,
					minorInjury: validCrashes.filter((c: any) => c.severity === 'Minor Injury').length,
					propertyOnly: validCrashes.filter((c: any) => c.severity === 'Property Damage Only').length
				};
				
				return { 
					count: validCrashes.length, 
					avg, 
					min, 
					max, 
					radiusMeters,
					severityCounts,
					crashes: validCrashes.slice(0, 5) // Include first 5 crashes for detailed info
				};
			} catch (error) {
				console.error('Error computing nearby stats:', error);
				return { count: 0 };
			}
		};

		const addDataAndLayers = () => {
			if (!map || !dcDataRef.current) {
				console.log('addDataAndLayers: map or data not ready', !!map, !!dcDataRef.current);
				return;
			}

			console.log('Adding data and layers, data has', dcDataRef.current.features.length, 'features');

			if (!map.getSource('dc-quakes')) {
				console.log('Creating new source');
				map.addSource('dc-quakes', { type: 'geojson', data: dcDataRef.current });
			} else {
				console.log('Updating existing source');
				(map.getSource('dc-quakes') as mapboxgl.GeoJSONSource).setData(dcDataRef.current);
			}

			if (!map.getLayer('dc-heat')) {
				map.addLayer({
					id: 'dc-heat', type: 'heatmap', source: 'dc-quakes', maxzoom: 15,
					paint: {
						'heatmap-weight': ['interpolate', ['linear'], ['get', 'mag'], 0, 0, 6, 1],
						'heatmap-intensity': heatIntensity,
						'heatmap-color': [
							'interpolate', 
							['linear'], 
							['heatmap-density'], 
							0, 'rgba(0,0,0,0)', 
							0.2, 'rgba(255,255,0,0.7)', 
							0.4, 'rgba(255,165,0,0.8)', 
							0.6, 'rgba(255,69,0,0.9)', 
							0.8, 'rgba(255,0,0,0.95)', 
							1, 'rgba(139,0,0,1)'
						],
						'heatmap-radius': heatRadius,
						'heatmap-opacity': ['interpolate', ['linear'], ['zoom'], 7, 1, 12, 0.8]
					}
				});
			}

			if (!map.getLayer('dc-point')) {
				map.addLayer({
					id: 'dc-point', type: 'circle', source: 'dc-quakes', minzoom: 12,
					paint: {
						'circle-radius': ['interpolate', ['linear'], ['get', 'mag'], 1, 3, 6, 10],
						'circle-color': [
							'interpolate', 
							['linear'], 
							['get', 'mag'], 
							1, styleChoiceRef.current === 'dark' ? '#ffff99' : '#ffa500',
							3, styleChoiceRef.current === 'dark' ? '#ff6666' : '#ff4500',
							6, styleChoiceRef.current === 'dark' ? '#ff0000' : '#8b0000'
						],
						'circle-opacity': ['interpolate', ['linear'], ['zoom'], 12, 0.7, 14, 0.9],
						'circle-stroke-width': 1,
						'circle-stroke-color': styleChoiceRef.current === 'dark' ? '#ffffff' : '#000000'
					}
				});
			}

			if (map.getLayer('dc-heat')) {
				map.setLayoutProperty('dc-heat', 'visibility', heatVisible ? 'visible' : 'none');
				map.setPaintProperty('dc-heat', 'heatmap-radius', heatRadius);
				map.setPaintProperty('dc-heat', 'heatmap-intensity', heatIntensity);
			}
			if (map.getLayer('dc-point')) {
				map.setLayoutProperty('dc-point', 'visibility', pointsVisible ? 'visible' : 'none');
			}
		};

		map.on('load', () => {
			console.log('Map loaded, adding initial data and layers');
			addDataAndLayers();
			// ensure map is fit to DC bounds initially
			try { map.fitBounds(dcBounds, { padding: 20 }); } catch (e) { /* ignore if fitBounds fails */ }

			map.on('click', 'dc-point', async (e) => {
				const feature = e.features && e.features[0];
				if (!feature) return;
				
				const coords = (feature.geometry as any).coordinates.slice() as [number, number];
				
				// Validate coordinates
				if (!coords || coords.length !== 2 || 
				    typeof coords[0] !== 'number' || typeof coords[1] !== 'number' ||
				    isNaN(coords[0]) || isNaN(coords[1]) || 
				    coords[0] === 0 || coords[1] === 0) {
					console.warn('Invalid coordinates for crash point:', coords);
					return;
				}
				
				const mag = feature.properties ? feature.properties.mag : undefined;
				const crashData = feature.properties ? feature.properties.crashData : undefined;
				const stats = await computeNearbyStats(coords, 300);
				
				let text = `Severity: ${mag ?? 'N/A'}`;
				if (crashData && crashData.address) {
					text = `Crash Report
Date: ${crashData.reportDate ? new Date(crashData.reportDate).toLocaleDateString() : 'Unknown'}
Address: ${crashData.address}
Vehicles: ${crashData.totalVehicles || 0} | Pedestrians: ${crashData.totalPedestrians || 0} | Bicycles: ${crashData.totalBicycles || 0}
Fatalities: ${(crashData.fatalDriver || 0) + (crashData.fatalPedestrian || 0) + (crashData.fatalBicyclist || 0)}
Major Injuries: ${(crashData.majorInjuriesDriver || 0) + (crashData.majorInjuriesPedestrian || 0) + (crashData.majorInjuriesBicyclist || 0)}`;
				}
				
				if (onPopupCreate) onPopupCreate({ lngLat: coords, mag, crashData, text, stats });
			});

			map.on('click', 'dc-heat', async (e) => {
				const p = e.point;
				const bbox = [[p.x - 6, p.y - 6], [p.x + 6, p.y + 6]] as [mapboxgl.PointLike, mapboxgl.PointLike];
				const nearby = map.queryRenderedFeatures(bbox, { layers: ['dc-point'] });
				if (nearby && nearby.length > 0) {
					const f = nearby[0];
					const coords = (f.geometry as any).coordinates.slice() as [number, number];
					
					// Validate coordinates
					if (!coords || coords.length !== 2 || 
					    typeof coords[0] !== 'number' || typeof coords[1] !== 'number' ||
					    isNaN(coords[0]) || isNaN(coords[1]) || 
					    coords[0] === 0 || coords[1] === 0) {
						console.warn('Invalid coordinates for heat map click:', coords);
						const stats = await computeNearbyStats([e.lngLat.lng, e.lngLat.lat], 300);
						if (onPopupCreate) onPopupCreate({ lngLat: [e.lngLat.lng, e.lngLat.lat], text: 'Zoom in to see individual crash reports and details', stats });
						return;
					}
					
					const mag = f.properties ? f.properties.mag : undefined;
					const crashData = f.properties ? f.properties.crashData : undefined;
					const stats = await computeNearbyStats(coords, 300);
					
					let text = `Severity: ${mag ?? 'N/A'}`;
					if (crashData && crashData.address) {
						text = `Crash Report
Date: ${crashData.reportDate ? new Date(crashData.reportDate).toLocaleDateString() : 'Unknown'}
Address: ${crashData.address}
Vehicles: ${crashData.totalVehicles || 0} | Pedestrians: ${crashData.totalPedestrians || 0} | Bicycles: ${crashData.totalBicycles || 0}
Fatalities: ${(crashData.fatalDriver || 0) + (crashData.fatalPedestrian || 0) + (crashData.fatalBicyclist || 0)}
Major Injuries: ${(crashData.majorInjuriesDriver || 0) + (crashData.majorInjuriesPedestrian || 0) + (crashData.majorInjuriesBicyclist || 0)}`;
					}
					
					if (onPopupCreate) onPopupCreate({ lngLat: coords, mag, crashData, text, stats });
				} else {
					const stats = await computeNearbyStats([e.lngLat.lng, e.lngLat.lat], 300);
					if (onPopupCreate) onPopupCreate({ lngLat: [e.lngLat.lng, e.lngLat.lat], text: 'Zoom in to see individual crash reports and details', stats });
				}
			});

			map.on('mouseenter', 'dc-point', () => map.getCanvas().style.cursor = 'pointer');
			map.on('mouseleave', 'dc-point', () => map.getCanvas().style.cursor = '');
			map.on('mouseenter', 'dc-heat', () => map.getCanvas().style.cursor = 'pointer');
			map.on('mouseleave', 'dc-heat', () => map.getCanvas().style.cursor = '');

			// Double-click handlers for enhanced nearby statistics
			map.on('dblclick', 'dc-point', async (e) => {
				e.preventDefault(); // Prevent default map zoom behavior
				
				const feature = e.features && e.features[0];
				if (!feature) return;
				
				const coords = (feature.geometry as any).coordinates.slice() as [number, number];
				
				// Validate coordinates
				if (!coords || coords.length !== 2 || 
				    typeof coords[0] !== 'number' || typeof coords[1] !== 'number' ||
				    isNaN(coords[0]) || isNaN(coords[1]) || 
				    coords[0] === 0 || coords[1] === 0) {
					console.warn('Invalid coordinates for crash point double-click:', coords);
					return;
				}
				
				// Get more comprehensive stats with larger radius for double-click
				const stats = await computeNearbyStats(coords, 500); // 500m radius for double-click
				const crashData = feature.properties ? feature.properties.crashData : undefined;
				
				let detailedText = 'Nearby Crash Analysis';
				if (crashData && crashData.address) {
					detailedText = `Detailed Analysis - ${crashData.address}`;
				}
				
				if (onPopupCreate) onPopupCreate({ 
					lngLat: coords, 
					crashData,
					text: detailedText, 
					stats 
				});
			});

			// Double-click on heatmap areas
			map.on('dblclick', 'dc-heat', async (e) => {
				e.preventDefault(); // Prevent default map zoom behavior
				
				const coords: [number, number] = [e.lngLat.lng, e.lngLat.lat];
				
				// Get comprehensive stats for the clicked location
				const stats = await computeNearbyStats(coords, 500); // 500m radius
				
				if (onPopupCreate) onPopupCreate({ 
					lngLat: coords, 
					text: 'Area Crash Analysis', 
					stats 
				});
			});

			// General map double-click for any location
			map.on('dblclick', async (e) => {
				// Only trigger if not clicking on a feature
				const features = map.queryRenderedFeatures(e.point, { layers: ['dc-point', 'dc-heat'] });
				if (features.length > 0) return; // Already handled by feature-specific handlers
				
				e.preventDefault(); // Prevent default map zoom behavior
				
				const coords: [number, number] = [e.lngLat.lng, e.lngLat.lat];
				
				// Get stats for any location on the map
				const stats = await computeNearbyStats(coords, 400); // 400m radius for general clicks
				
				if (stats.count > 0) {
					if (onPopupCreate) onPopupCreate({ 
						lngLat: coords, 
						text: 'Location Analysis', 
						stats 
					});
				} else {
					if (onPopupCreate) onPopupCreate({ 
						lngLat: coords, 
						text: 'No crashes found in this area', 
						stats: { count: 0, radiusMeters: 800 }
					});
				}
			});
		});

		map.on('styledata', () => {
			if (!map.getSource('dc-quakes')) {
				addDataAndLayers();
			}
		});

		if (onMapReady) onMapReady(map);

		return () => {
			if (mapRef.current) {
				mapRef.current.remove();
				mapRef.current = null;
			}
		};
	}, []);

	// update visibility & paint when props change
	useEffect(() => {
		const map = mapRef.current;
		if (!map) return;
		if (map.getLayer && map.getLayer('dc-heat')) {
			map.setLayoutProperty('dc-heat', 'visibility', heatVisible ? 'visible' : 'none');
			map.setPaintProperty('dc-heat', 'heatmap-radius', heatRadius);
			map.setPaintProperty('dc-heat', 'heatmap-intensity', heatIntensity);
		}
		if (map.getLayer && map.getLayer('dc-point')) {
			map.setLayoutProperty('dc-point', 'visibility', pointsVisible ? 'visible' : 'none');
		}
	}, [heatRadius, heatIntensity, heatVisible, pointsVisible]);

	return (
		// container should fill its parent so parent can control sizing (flex)
		<div ref={containerRef} style={{ position: 'relative', width: '100%', height: '100%' }}>
			<div ref={mapContainerRef} style={{ width: '100%', height: '100%' }} />
		</div>
	);
}