let map, panorama, guessMarker, gameId, googleMapsApiKey;
let startLocation;
let onFirstLinksLoaded;

function api(path) {
    // Use relative paths so mounting under a subpath works
    return path.startsWith('/') ? path.slice(1) : path;
}

function initLobby() {
    const replayForm = document.getElementById('replay-form');
    if (replayForm) {
        replayForm.addEventListener('submit', (e) => {
            e.preventDefault();
            replayGame();
        });
    }
    const playAgain = document.getElementById('play-again');
    if (playAgain) {
        playAgain.addEventListener('click', showLobby);
    }
}

function showLobby() {
    document.getElementById('lobby-container').style.display = 'block';
    document.getElementById('game-container').style.display = 'none';
    document.getElementById('result-screen').style.display = 'none';
}

function showGame() {
    document.getElementById('lobby-container').style.display = 'none';
    document.getElementById('game-container').style.display = 'flex';
    document.getElementById('result-screen').style.display = 'none';
}

function startGame() {
    showGame();
    const difficultyEl = document.getElementById('difficulty-select-lobby');
    const difficulty = difficultyEl ? difficultyEl.value : 'easy';
    fetch(api('/start_game'), {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ difficulty: difficulty })
    })
        .then(response => response.json())
        .then(data => {
            if (data.error) {
                alert(data.error);
                showLobby();
                return;
            }
            gameId = data.game_id;
            startLocation = data.start_location || null;
            googleMapsApiKey = data.google_maps_api_key || null;

            const chatLog = document.getElementById('chat-log');
            chatLog.innerHTML = '';
            addChatMessage('Agent', `New game started (ID: ${gameId}). Finding my location...`);

            if (startLocation) {
                initStreetView(startLocation);
                initMap();
            }
        });
}

function replayGame() {
    const replayId = document.getElementById('replay-id-input').value;
    if (!replayId) {
        alert('Please enter a Game ID to replay.');
        return;
    }

    fetch(api(`/game/${replayId}/state`))
        .then(response => {
            if (!response.ok) {
                throw new Error('Game not found.');
            }
            return response.json();
        })
        .then(data => {
            if (!data.game_over) {
                alert('This game has not finished yet.');
                return;
            }
            showGame();
            gameId = replayId;
            startLocation = data.start_location;

            const chatLog = document.getElementById('chat-log');
            chatLog.innerHTML = '';
            addChatMessage('System', `Replaying game: ${gameId}`);

            initStreetView(startLocation);
            initMap(true);
            replayActions(data.actions);
        })
        .catch(error => {
            alert(error.message);
        });
}

async function replayActions(actions) {
    for (const action of actions) {
        await sleep(2000);
        if (action.type === 'move') {
            addChatMessage('Agent (Replay)', `Moved to: ${action.location.lat.toFixed(4)}, ${action.location.lng.toFixed(4)}`);
            panorama.setPosition(action.location);
        } else if (action.type === 'guess') {
            addChatMessage('Agent (Replay)', `Guessed: ${action.location.lat.toFixed(4)}, ${action.location.lng.toFixed(4)}`);
            placeGuessMarker(action.location);
            await sleep(2000);
            const resultData = {
                guess_location: action.location,
                actual_location: startLocation,
                distance_km: action.result.distance_km,
                score: action.result.score
            };
            showResultScreen(resultData);
        }
    }
}

function initStreetView(location) {
    onFirstLinksLoaded = new Promise(resolve => {
        panorama = new google.maps.StreetViewPanorama(
            document.getElementById('streetview'), {
                position: location,
                pov: { heading: 34, pitch: 10 },
                visible: true,
                linksControl: true,
                clickToGo: true,
            }
        );

        const linksChangedListener = panorama.addListener('links_changed', () => {
            google.maps.event.removeListener(linksChangedListener);
            resolve();
        });

        panorama.addListener('position_changed', function() {
            const newLocation = panorama.getPosition();
            updateAgentLocation(newLocation.lat(), newLocation.lng());
        });
    });
}

function initMap(isReplay = false) {
    map = new google.maps.Map(document.getElementById('map'), {
        center: { lat: 0, lng: 0 },
        zoom: 1,
    });

    if (!isReplay) {
        map.addListener('click', function(e) {
            placeGuessMarker(e.latLng);
            makeGuess(e.latLng.lat(), e.latLng.lng());
        });
    }
}

function placeGuessMarker(location) {
    if (guessMarker) {
        guessMarker.setMap(null);
    }
    guessMarker = new google.maps.Marker({
        position: location,
        map: map
    });
    map.setCenter(location);
}

function addChatMessage(sender, message) {
    const chatLog = document.getElementById('chat-log');
    const messageElement = document.createElement('div');
    messageElement.innerHTML = `<strong>${sender}:</strong> ${message}`;
    chatLog.appendChild(messageElement);
    chatLog.scrollTop = chatLog.scrollHeight;
}

async function runFakeAgent() {}

async function takeActionWithScreenshot(actionMessage) {}

async function updateAgentLocation(lat, lng) {
    await fetch(api(`/game/${gameId}/move`), {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ lat: lat, lng: lng }),
    });
}

async function makeGuess(lat, lng) {
    addChatMessage('You', `Guessed: ${lat.toFixed(4)}, ${lng.toFixed(4)}`);
    const response = await fetch(api(`/game/${gameId}/guess`), {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ lat: lat, lng: lng }),
    });
    const result = await response.json();
    showResultScreen(result);
}

function showResultScreen(result) {
    document.getElementById('game-container').style.display = 'none';
    document.getElementById('result-screen').style.display = 'block';

    const resultSummary = document.getElementById('result-summary');
    resultSummary.innerHTML = `
        <p>Your guess was ${result.distance_km.toFixed(2)} km away.</p>
        <p>You scored ${result.score.toFixed(0)} points.</p>
    `;

    const resultMap = new google.maps.Map(document.getElementById('result-map'), {
        zoom: 3,
        center: result.actual_location
    });

    new google.maps.Marker({
        position: result.actual_location,
        map: resultMap,
        label: 'A'
    });
    new google.maps.Marker({
        position: result.guess_location,
        map: resultMap,
        label: 'G'
    });
    new google.maps.Polyline({
        path: [result.actual_location, result.guess_location],
        geodesic: true,
        strokeColor: '#F97316',
        strokeOpacity: 1.0,
        strokeWeight: 2,
        map: resultMap
    });
}

function sleep(ms) {
    return new Promise(resolve => setTimeout(resolve, ms));
}