"use strict";

let puzzeltocht = undefined;
window.addEventListener("DOMContentLoaded", () => {
    puzzeltocht = new Puzzeltocht();
});

class Puzzeltocht {

    constructor() {
        this.joinScreen = new JoinScreen();
        this.location = new LocationApi();
        console.log("puzzeltocht initialised");
    }

    startEvent(eventId, teamId) {
        this.eventId = this.joinScreen.eventId;
        this.teamId = teamId;
        document.getElementById("join").style.display = "none";
        document.getElementById("mission").style.display = "block";
        document.getElementById("questionMission").style.display = "none";
        this.location.enable(p => this.updateLocation(p))
    }

    updateLocation(position) {
        let l = document.getElementById("location");
        if (position.accuracy() > 20) {
            l.innerText = "Onbetrouwbare locatie: " + position.string();
            return;
        }

        l.innerText = position.string();

        if (this.lastUpdate === undefined || Date.now() - this.lastUpdate > 5000) {
            Api.sendLocation(this.eventId, this.teamId, position)
                .then(m => this.updateMission(m))
                .catch(e => this.onError(e));
            this.lastUpdate = Date.now();
        }
    }

    updateMission(m) {
        this.mission = m;
        document.getElementById("missionTitle").innerText = m.title + " (" + m.distanceToTarget + "m)";
        document.getElementById("missionDescription").innerText = m.description;
    }

    onError(e) {
        this.location.disable();
        let l = document.getElementById("location");
        l.innerText = "Error!";
        console.log(e);
    }

}

class JoinScreen {

    constructor() {
        Api.fetchEvents()
            .then(JoinScreen.showEvents)
            .catch(console.log);
        document.getElementById("joinForm").addEventListener("submit", (e) => this.joinEvent(e));
    }

    joinEvent(submitEvent) {
        submitEvent.preventDefault();
        let form = document.getElementById("joinForm");
        this.eventId = form.elements["eventId"].value;
        let teamName = form.elements["teamName"].value;

        if (this.eventId === "" || teamName === "") {
            console.log("required form field empty");
            return;
        }

        document.getElementById("joinButton").disabled = true;

        Api.join(this.eventId, teamName)
            .then(teamId => puzzeltocht.startEvent(this.eventId, teamId))
            .catch(r => {
                console.log(r);
                document.getElementById("joinButton").disabled = false;
            });
    }

    static showEvents(eventJson) {
        let events = document.getElementById("events");
        events.innerHTML = "";
        eventJson.forEach((e) => {
            events.innerHTML += '<label><input name="eventId" value="' + e.id + '" type="radio">' + e.title + '</label>';
        });
        document.getElementById("joinButton").disabled = false;
    }

}

class Api {

    static fetchEvents() {
        return FetchJson.get("/api/event")
    }

    static join(eventId, teamName) {
        let url = "/api/event/" + encodeURIComponent(eventId) + "/team";
        return FetchJson.post(url, teamName);
    }

    static sendLocation(eventId, teamId, position) {
        let body = {
            location: {latitude: position.lat(), longitude: position.lon()},
            answer: null,
        };
        let url = "/api/event/" + encodeURIComponent(eventId) + "/team/" + encodeURIComponent(teamId);
        return FetchJson.put(url, body);
    }


}

class FetchJson {

    static get(url) {
        return fetch(url, {method: "GET"})
            .then(FetchJson.responseBody)
    }

    static post(url, body) {
        let options = {
            method: "POST",
            headers: {"Content-Type": "application/json"},
            body: JSON.stringify(body)
        };
        return fetch(url, options)
            .then(FetchJson.responseBody)
    }

    static put(url, body) {
        let options = {
            method: "PUT",
            headers: {"Content-Type": "application/json"},
            body: JSON.stringify(body)
        };
        return fetch(url, options)
            .then(FetchJson.responseBody)
    }

    static responseBody(r) {
        if (!r.ok) {
            throw Error("HTTP " + r.status + " " + r.statusText + " " + r.url);
        }
        return r.json();
    }

}

class Location {

    constructor(pos) {
        this.pos = pos;
    }

    accuracy() {
        return this.pos.coords.accuracy.toFixed(1)
    }

    age() {
        return Date.now() - this.pos.timestamp;
    }

    lat() {
        return this.pos.coords.latitude.toFixed(5);
    }

    lon() {
        return this.pos.coords.longitude.toFixed(5);
    }

    string() {
        return "(" + this.lat() + ", " + this.lon() + ")"
        + " +-" + this.accuracy() + "m, " + this.age() + "s geleden"
    }
}

class LocationApi {

    constructor() {
        if ("geolocation" in navigator) {
            console.log("Geolocation API available");
        } else {
            console.log("Geolocation API not available");
            document.getElementById("unsupported").style.display = "block";
        }

        if (window.isSecureContext) {
            console.log("Secure context available");
        } else {
            console.log("Secure context not available");
            document.getElementById("unsupported").style.display = "block";
        }
    }

    disable() {
        console.log("disabling geolocation watch " + this.watchId);
        navigator.geolocation.clearWatch(this.watchId);
    }

    enable(callback) {
        const geoOpts = {
            enableHighAccuracy: true,
            maximumAge: 10000,
            timeout: 9500
        };

        this.watchId = navigator.geolocation.watchPosition(
            (pos) => callback(new Location(pos)),
            (err) => console.log(err),
            geoOpts);
    }

}