let apiBaseUrl = 'http://localhost:3000/api/v1';
const processingList = [];

async function checkConnectivity() {
    try {
        const response = await fetch(`${apiBaseUrl}/ping`);
        if (!response.ok) {
            document.getElementById('connectivity-status').classList.remove('hidden');
            return;
        }
        document.getElementById('connectivity-status').classList.add('hidden');
    } catch {
        document.getElementById('connectivity-status').classList.remove('hidden');
    }
}

function setApiUrl() {
    const url = document.getElementById('api-url');

    if (url === null || url.value === '') {
        console.log('Using default API URL');
        apiBaseUrl = `http://${window.location.hostname}:3000/api/v1`;
    } else {
        apiBaseUrl = url.value;
    }
}

async function sendAdd(url) {
    return fetch(`${apiBaseUrl}/queue`, {
        method: 'POST',
        headers: {
            'Content-Type': 'application/json'
        },
        body: JSON.stringify({song: url})
    });
}

async function addToQueue() {
    const song = document.getElementById('song-url');
    if (!song || !(song instanceof HTMLInputElement)) {
        alert('Failed to find song URL input');
        return;
    }

    const url = song.value;

    if (!url) {
        alert('Please enter a song URL');
        return;
    }

    const response = await sendAdd(url);
    if (response.ok) {
        loadQueue();
        song.value = '';
    } else {
        const errorMessage = await response.text();
        alert(`Failed to add song to queue: ${errorMessage}`);
    }
}

async function deleteFromQueue(item) {
    const song = encodeURIComponent(item.song.url);
    const response = await fetch(`${apiBaseUrl}/queue/${song}`, {
        method: 'DELETE'
    });

    if (response.ok) {
        loadQueue();
    } else {
        const errorMessage = await response.text();
        alert(`Failed to delete song from queue: ${errorMessage}`);
    }
}

async function retry(item) {
    const song = encodeURIComponent(item.song.url);
    const response = await fetch(`${apiBaseUrl}/queue/retry/${song}`, {
        method: 'POST'
    });

    if (response.ok) {
        loadQueue();
        loadHistory();
    } else {
        const errorMessage = await response.text();
        alert(`Failed to retry song: ${errorMessage}`);
    }
}

async function clearQueue() {
    // Show a confirmation dialog
    if (!confirm('Are you sure you want to clear the queue?')) {
        return;
    }

    const response = await fetch(`${apiBaseUrl}/queue`, {
        method: 'DELETE'
    });

    if (response.ok) {
        loadQueue();
    } else {
        const errorMessage = await response.text();
        alert(`Failed to clear queue: ${errorMessage}`);
    }
}

async function loadQueue() {
    const response = await fetch(`${apiBaseUrl}/queue`);
    const queue = await response.json();

    const queueList = document.getElementById('queue');
    if (!queueList) {
        alert('Failed to find queue list');
        return;
    }

    queueList.innerHTML = '';
    queue.forEach(item => {
        const element = constructQueueItem(item);

        const deleteButton = document.createElement('button');
        deleteButton.classList.add('delete');
        deleteButton.textContent = 'x';
        deleteButton.addEventListener('click', () => deleteFromQueue(item));
        element.prepend(deleteButton);

        queueList.appendChild(element);
    });
}

async function loadProcessing() {
    const response = await fetch(`${apiBaseUrl}/queue/processing`);
    const status = await response.json();

    const processingDiv = document.getElementById('currently-processing');
    if (!processingDiv) {
        alert('Failed to find processing status element');
        return;
    }

    if (status.length === 0) {
        processingDiv.textContent = 'Nothing processing';
    }

    status.forEach(item => {
        // Add new items if they are not already in the list
        if (!processingList.some(element => element.id === item.item.id)) {
            const listItem = constructQueueItem(item.item);

            const details = document.createElement('details');
            details.id = item.item.id;

            const summary = document.createElement('summary');
            summary.innerHTML = listItem.innerHTML
            details.appendChild(summary);

            const trackCount = document.createElement('p');
            trackCount.innerText = item.item.song.trackCount + ' tracks';
            details.appendChild(trackCount);

            const progress = document.createElement('p');
            progress.classList.add('progress');
            progress.textContent = item.status;
            details.appendChild(progress);

            processingDiv.appendChild(details);
            processingList.push(details);
        } else {
            // Update the progress of existing items
            const element = processingList.find(element => element.id === item.item.id);
            const progress = element.querySelector('.progress');
            progress.innerText = item.status;
        }
    });

    // Remove items that are no longer processing
    const toRemove = processingList.filter(element => !status.some(item => item.item.id === element.id));
    toRemove.forEach(element => {
        console.log('Removing', element);
        processingList.splice(processingList.indexOf(element), 1);
        element.remove();

        // Add the item to the history
        const historyList = document.getElementById('history');
        if (!historyList) {
            alert('Failed to find history list');
            return;
        }
        historyList.prepend(element.querySelector('summary'));
    });
}

async function loadHistory() {
    const response = await fetch(`${apiBaseUrl}/queue/history`);
    const history = await response.json();

    const historyList = document.getElementById('history');
    if (!historyList) {
        alert('Failed to find history list');
        return;
    }

    historyList.innerHTML = '';
    history.reverse().forEach(item => {
        const element = constructQueueItem(item);

        if (!item.result.success) {
            const retryButton = document.createElement('button');
            retryButton.classList.add('retry');
            retryButton.textContent = 'Retry';
            retryButton.addEventListener('click', () => retry(item));
            element.appendChild(retryButton);
        }

        historyList.appendChild(element);
    })
}

function getSourceIcon(item) {
    const sourceToIcon = new Map([
        ['spotify', 's'],
        ['qobuz', 'q'],
        ['unknown', '?']
    ]);

    return sourceToIcon.get(item.song.source) ?? '?';
}

function getState(item) {
    const state = document.createElement('span');
    state.classList.add('state');
    if (!item.result) {
        state.textContent = '⌛';
        state.title = 'Processing';
    } else {
        state.textContent = item.result.success ? '✓' : '✗';
        state.title = item.result.success ? 'Processed' : 'Failed: ' + item.result.error;
    }
    return state;
}

function getCoverImage(item) {
    const img = document.createElement('img');
    img.src = item.song.cover || "./assets/cover-default.png";
    img.alt = `${item.song.title} - ${item.song.artist}`;
    img.classList.add('cover-art');
    return img;
}

function constructQueueItem(item) {
    const element = document.createElement('li');

    const title = document.createElement('span');
    title.classList.add('title');
    title.textContent = `${item.song.title} - ${item.song.artist}`;
    element.appendChild(title);

    const coverImage = getCoverImage(item);
    element.prepend(coverImage);

    const source = document.createElement('span');
    source.classList.add('source');
    source.textContent = getSourceIcon(item);
    const link = document.createElement('a');
    link.href = item.song.url;
    link.appendChild(source);
    element.appendChild(link);

    element.appendChild(getState(item));

    return element;
}

function setup() {
    const addSongButton = document.getElementById('add-song');
    if (!addSongButton) {
        alert('Failed to find add song button');
        return;
    }
    addSongButton.addEventListener('click', addToQueue);
    const addSongInput = document.getElementById('song-url');
    if (!addSongInput) {
        alert('Failed to find song URL input');
        return;
    }
    addSongInput.addEventListener('keydown', (event) => {
        if (event.key === 'Enter') {
            addToQueue();
        }
    });
    addSongInput.addEventListener('drop', (event) => {
        event.preventDefault();
        addSongInput.value = event.dataTransfer.getData('text');
        addToQueue();
    });

    const refreshQueueButton = document.getElementById('refresh-queue');
    if (!refreshQueueButton) {
        alert('Failed to find refresh queue button');
        return;
    }
    refreshQueueButton.addEventListener('click', loadQueue);

    const clearQueueButton = document.getElementById('clear-queue');
    if (!clearQueueButton) {
        alert('Failed to find clear queue button');
        return;
    }
    clearQueueButton.addEventListener('click', clearQueue);

    const apiUrlButton = document.getElementById('set-api');
    if (!apiUrlButton) {
        alert('Failed to find set API URL button');
        return;
    }
    apiUrlButton.addEventListener('click', setApiUrl);

    document.addEventListener('DOMContentLoaded', () => {
        setApiUrl();
        loadQueue();
        loadHistory();
        checkConnectivity();

        setInterval(checkConnectivity, 5000);
        setInterval(loadProcessing, 5000);
    });
}

setup();