/**
 * Hugging Face OAuth Authentication and Space Management
 * Uses @huggingface/hub library for OAuth flow
 *
 * Note: The public space now supports secure multi-user connections with per-user isolation.
 * Cloning a private space is optional - most users can use the public space safely.
 */

import { oauthLoginUrl, oauthHandleRedirectIfPresent, uploadFile, createRepo } from "https://cdn.jsdelivr.net/npm/@huggingface/hub@0.15.2/+esm";

const HF_API = 'https://huggingface.co/api';
const NEW_SPACE_NAME = 'reachy_mini_remote_control';

// State management
let currentUser = null;
let userToken = null;
let oauthResult = null;

/**
 * Initialize OAuth and check authentication status
 */
async function initAuth() {
    try {
        // Check if we're returning from OAuth redirect
        oauthResult = await oauthHandleRedirectIfPresent();

        if (oauthResult) {
            // User just authenticated via OAuth
            console.log('OAuth result:', oauthResult);
            console.log('User info:', oauthResult.userInfo);
            console.log('All userInfo keys:', Object.keys(oauthResult.userInfo));

            // Extract username from fullname field (HuggingFace uses fullname for the username)
            currentUser = oauthResult.userInfo.fullname;
            userToken = oauthResult.accessToken;

            console.log('Extracted username:', currentUser);
            console.log('Extracted token:', userToken ? 'present' : 'missing');

            // Store for session (not persistent across page reloads by design)
            sessionStorage.setItem('hf_token', userToken);
            sessionStorage.setItem('hf_username', currentUser);
            sessionStorage.setItem('hf_token_expires', oauthResult.accessTokenExpiresAt);

            console.log('OAuth authentication successful:', currentUser);
            showAuthenticatedView();
            await checkForExistingSpace();
        } else {
            // Check if we have a stored session
            const storedToken = sessionStorage.getItem('hf_token');
            const storedUser = sessionStorage.getItem('hf_username');
            const tokenExpires = sessionStorage.getItem('hf_token_expires');

            if (storedToken && storedUser && tokenExpires && new Date(tokenExpires) > new Date()) {
                // Valid session exists
                userToken = storedToken;
                currentUser = storedUser;
                showAuthenticatedView();
                await checkForExistingSpace();
            }
        }
    } catch (error) {
        console.error('OAuth initialization error:', error);
        // Show login view on error
        showLoginView();
    }
}

/**
 * Redirect to Hugging Face OAuth login
 */
async function loginToHuggingFace() {
    try {
        // Generate OAuth login URL and redirect
        const loginUrl = await oauthLoginUrl();
        window.location.href = loginUrl;
    } catch (error) {
        console.error('OAuth login error:', error);
        alert('Failed to initiate login. Please try again.');
    }
}

/**
 * Show the login view
 */
function showLoginView() {
    document.getElementById('login-view').style.display = 'block';
    document.getElementById('authenticated-view').style.display = 'none';
}

/**
 * Show authenticated user view
 */
function showAuthenticatedView() {
    console.log('Showing authenticated view for user:', currentUser);
    document.getElementById('login-view').style.display = 'none';
    document.getElementById('authenticated-view').style.display = 'block';
    // Display username (from fullname field)
    document.getElementById('username').textContent = `@${currentUser}`;
}

/**
 * Check if user already has the space
 */
async function checkForExistingSpace() {
    try {
        const response = await fetch(`${HF_API}/spaces/${currentUser}/${NEW_SPACE_NAME}`, {
            headers: {
                'Authorization': `Bearer ${userToken}`
            }
        });

        if (response.ok) {
            showExistingSpaceView();
        } else {
            showNoSpaceView();
        }
    } catch (error) {
        console.error('Error checking for space:', error);
        showNoSpaceView();
    }
}

/**
 * Show view for users who don't have the space yet
 */
function showNoSpaceView() {
    document.getElementById('no-space-view').style.display = 'block';
    document.getElementById('has-space-view').style.display = 'none';
}

/**
 * Show view for users who already have the space
 */
function showExistingSpaceView() {
    document.getElementById('no-space-view').style.display = 'none';
    document.getElementById('has-space-view').style.display = 'block';

    // Update space URL displays
    const spaceUrl = `${currentUser}/${NEW_SPACE_NAME}`;
    // HuggingFace converts underscores to hyphens in subdomain URLs
    // Example: andito/reachy_mini_remote_control -> andito-reachy-mini-remote-control.hf.space
    const wsUri = `wss://${currentUser}-${NEW_SPACE_NAME.replace(/_/g, '-')}.hf.space`;

    document.getElementById('space-url-display').textContent = spaceUrl;
    document.getElementById('private-uri').textContent = wsUri;
    document.getElementById('space-link').href = `https://huggingface.co/spaces/${spaceUrl}`;
}

/**
 * Create a new space and upload files
 */
async function cloneSpace() {
    const btn = document.querySelector('#no-space-view .btn');
    const btnText = document.getElementById('clone-btn-text');
    const originalText = btnText.textContent;

    try {
        // Verify we have user credentials
        if (!currentUser || !userToken) {
            throw new Error('Not authenticated. Please sign in again.');
        }

        // Update button state
        btn.disabled = true;
        btnText.textContent = '⏳ Creating space...';

        console.log('Creating space for user:', currentUser);
        console.log('Creating repo:', `${currentUser}/${NEW_SPACE_NAME}`);

        // Step 1: Create the space repository using @huggingface/hub
        const createResult = await createRepo({
            repo: {
                type: 'space',
                name: `${currentUser}/${NEW_SPACE_NAME}`
            },
            accessToken: userToken,
            credentials: {
                accessToken: userToken
            },
            hubUrl: 'https://huggingface.co',
            spaceHardware: 'cpu-basic',
            spaceSdk: 'gradio',
            private: true
        });

        console.log('Repo created successfully:', createResult);
        btnText.textContent = '⏳ Uploading files...';

        // Step 2: Upload files to the space from local directory
        const files = ['README.md', 'app.py', 'requirements.txt', 'packages.txt', 'dist.zip'];

        for (const fileName of files) {
            console.log(`Fetching ${fileName}...`);
            // Fetch file content from local remote_control_space directory
            const fileResponse = await fetch(`remote_control_space/${fileName}`);
            if (!fileResponse.ok) {
                console.error(`Failed to fetch ${fileName}`);
                continue;
            }
            const content = await fileResponse.blob();

            console.log(`Uploading ${fileName}...`);
            // Upload to space using @huggingface/hub
            const uploadResult = await uploadFile({
                repo: {
                    type: 'space',
                    name: `${currentUser}/${NEW_SPACE_NAME}`
                },
                accessToken: userToken,
                credentials: {
                    accessToken: userToken
                },
                file: {
                    path: fileName,
                    content: content
                }
            });
            console.log(`${fileName} uploaded:`, uploadResult);
        }

        btnText.textContent = '✓ Space created successfully!';

        // Wait a moment then show the space view
        setTimeout(() => {
            showExistingSpaceView();
        }, 1500);

    } catch (error) {
        console.error('Error creating space:', error);
        alert(`Failed to create space: ${error.message}\n\nPlease try again or create the space manually.`);
        btn.disabled = false;
        btnText.textContent = originalText;
    }
}

/**
 * Logout and clear stored credentials
 */
function logout() {
    if (confirm('Are you sure you want to sign out?')) {
        localStorage.removeItem('hf_token');
        localStorage.removeItem('hf_username');
        currentUser = null;
        userToken = null;

        // Reset UI
        document.getElementById('login-view').style.display = 'block';
        document.getElementById('authenticated-view').style.display = 'none';
    }
}

/**
 * Copy text to clipboard
 */
function copyToClipboard(text, buttonElement) {
    navigator.clipboard.writeText(text).then(() => {
        // Visual feedback
        if (buttonElement) {
            const originalText = buttonElement.textContent;
            buttonElement.textContent = '✓ Copied!';
            setTimeout(() => {
                buttonElement.textContent = originalText;
            }, 2000);
        }
    }).catch(err => {
        console.error('Failed to copy:', err);
        alert('Failed to copy to clipboard');
    });
}

/**
 * Copy private URI to clipboard
 */
function copyPrivateUri(event) {
    const uri = document.getElementById('private-uri').textContent;
    copyToClipboard(uri, event.currentTarget);
}

// Expose functions globally for onclick handlers
window.loginToHuggingFace = loginToHuggingFace;
window.cloneSpace = cloneSpace;
window.logout = logout;
window.copyToClipboard = copyToClipboard;
window.copyPrivateUri = copyPrivateUri;

// Initialize on page load
document.addEventListener('DOMContentLoaded', initAuth);