import axios from "axios";

const TOMTOM_API_KEY = "MERY8I7LMeYVSLKO5WuV73W9rKJpBLoB";

export interface LatLng {
    latitude: number;
    longitude: number;
}

export interface RouteInfo {
    distance: string;
    duration: string;
    distanceMeters: number;
    durationSeconds: number;
    coordinates: LatLng[];
}

export interface NavigationInstruction {
    instruction: string;
    distance: string;
    maneuver: string;
    streetName?: string;
    isActive: boolean;
}

export const maneuverTranslations: Record<string, string> = {
    TURN_LEFT: "Tournez à gauche",
    TURN_RIGHT: "Tournez à droite",
    TURN_SLIGHT_LEFT: "Tournez légèrement à gauche",
    TURN_SLIGHT_RIGHT: "Tournez légèrement à droite",
    TURN_SHARP_LEFT: "Tournez fortement à gauche",
    TURN_SHARP_RIGHT: "Tournez fortement à droite",
    KEEP_LEFT: "Restez à gauche",
    KEEP_RIGHT: "Restez à droite",
    STRAIGHT: "Continuez tout droit",
    ENTER_ROUNDABOUT: "Entrez dans le rond-point",
    EXIT_ROUNDABOUT: "Sortez du rond-point",
    MOTORWAY_ENTER: "Entrez sur l'autoroute",
    MOTORWAY_EXIT: "Sortez de l'autoroute",
    ARRIVE: "Vous êtes arrivé",
    ARRIVE_LEFT: "Destination à gauche",
    ARRIVE_RIGHT: "Destination à droite",
    DEPART: "Départ",
    U_TURN: "Faites demi-tour",
    FOLLOW: "Suivez",
    WAYPOINT_REACHED: "Point de passage atteint",
};

export const maneuverIcons: Record<string, string> = {
    TURN_LEFT: "arrow-back",
    TURN_RIGHT: "arrow-forward",
    TURN_SLIGHT_LEFT: "arrow-up",
    TURN_SLIGHT_RIGHT: "arrow-up",
    TURN_SHARP_LEFT: "return-down-back",
    TURN_SHARP_RIGHT: "return-down-forward",
    KEEP_LEFT: "arrow-back",
    KEEP_RIGHT: "arrow-forward",
    STRAIGHT: "arrow-up",
    ENTER_ROUNDABOUT: "sync",
    EXIT_ROUNDABOUT: "arrow-forward",
    MOTORWAY_ENTER: "speedometer",
    MOTORWAY_EXIT: "exit-outline",
    ARRIVE: "flag",
    ARRIVE_LEFT: "flag",
    ARRIVE_RIGHT: "flag",
    DEPART: "car",
    U_TURN: "return-up-back",
    FOLLOW: "arrow-up",
    WAYPOINT_REACHED: "location",
    DEFAULT: "arrow-up",
};

// ---- Helpers ----
function formatDistance(meters: number): string {
    if (meters < 1000) return `${Math.round(meters)} m`;
    return `${(meters / 1000).toFixed(1)} km`;
}

export async function geocodeAddress(address: string): Promise<LatLng | null> {
    try {
        const url = `https://api.tomtom.com/search/2/geocode/${encodeURIComponent(address)}.json?key=${TOMTOM_API_KEY}&limit=1`;
        const { data } = await axios.get(url);
        if (data.results && data.results.length > 0) {
            const pos = data.results[0].position;
            if (pos?.lat != null && pos?.lon != null) {
                return { latitude: pos.lat, longitude: pos.lon };
            }
        }
    } catch {
        /* silent */
    }
    return null;
}

export async function calculateRoute(
    origin: LatLng,
    destination: LatLng,
): Promise<{ route: RouteInfo; instructions: NavigationInstruction[] } | null> {
    try {
        const start = `${origin.latitude},${origin.longitude}`;
        const end = `${destination.latitude},${destination.longitude}`;
        const url = `https://api.tomtom.com/routing/1/calculateRoute/${start}:${end}/json?key=${TOMTOM_API_KEY}&instructionsType=text&language=fr-FR&traffic=true&travelMode=car`;

        const { data } = await axios.get(url);

        if (!data.routes || data.routes.length === 0) return null;

        const route = data.routes[0];
        const summary = route.summary;

        // Extract polyline coordinates
        const coordinates: LatLng[] = [];
        if (route.legs) {
            for (const leg of route.legs) {
                if (leg.points) {
                    for (const pt of leg.points) {
                        coordinates.push({
                            latitude: pt.latitude,
                            longitude: pt.longitude,
                        });
                    }
                }
            }
        }

        // Fallback: straight line
        if (coordinates.length === 0) {
            coordinates.push(origin, destination);
        }

        const distanceKm = (summary.lengthInMeters / 1000).toFixed(1);
        const durationMin = Math.round(summary.travelTimeInSeconds / 60);

        const routeInfo: RouteInfo = {
            distance: `${distanceKm} km`,
            duration: `${durationMin} min`,
            distanceMeters: summary.lengthInMeters,
            durationSeconds: summary.travelTimeInSeconds,
            coordinates,
        };

        // Extract instructions
        const instructions: NavigationInstruction[] = [];
        if (route.guidance?.instructions) {
            for (let i = 0; i < route.guidance.instructions.length; i++) {
                const inst = route.guidance.instructions[i];
                const maneuver = inst.maneuver || "STRAIGHT";
                const text =
                    inst.message ||
                    maneuverTranslations[maneuver] ||
                    "Continuez";
                instructions.push({
                    instruction: text,
                    distance: formatDistance(inst.routeOffsetInMeters || 0),
                    maneuver,
                    streetName: inst.street,
                    isActive: i === 0,
                });
            }
        }

        if (instructions.length === 0) {
            instructions.push({
                instruction: "Dirigez-vous vers votre destination",
                distance: formatDistance(summary.lengthInMeters || 0),
                maneuver: "DEPART",
                isActive: true,
            });
            instructions.push({
                instruction: "Vous êtes arrivé à destination",
                distance: "0 m",
                maneuver: "ARRIVE",
                isActive: false,
            });
        }

        return { route: routeInfo, instructions };
    } catch {
        /* silent */
    }
    return null;
}

// ---- Bearing calculation ----
export function calculateBearing(from: LatLng, to: LatLng): number {
    const φ1 = (from.latitude * Math.PI) / 180;
    const φ2 = (to.latitude * Math.PI) / 180;
    const Δλ = ((to.longitude - from.longitude) * Math.PI) / 180;
    const y = Math.sin(Δλ) * Math.cos(φ2);
    const x =
        Math.cos(φ1) * Math.sin(φ2) -
        Math.sin(φ1) * Math.cos(φ2) * Math.cos(Δλ);
    return ((Math.atan2(y, x) * 180) / Math.PI + 360) % 360;
}