/**
 * Version Fetcher - Automatically fetches and displays latest pyserveX version
 * from Gitea releases page
 */

(function() {
    'use strict';
    const RELEASES_URL = 'https://git.pyserve.org/Shifty/pyserveX/releases/latest';
    const VERSION_ELEMENT_ID = 'current-version';
    const CACHE_KEY = 'pyserve_version_cache';
    const CACHE_DURATION = 3600000; // 1 hour
    const FALLBACK_VERSION = 'offline';
    
    async function fetchLatestVersion() {
        try {
            const response = await fetch(RELEASES_URL, {
                method: 'GET',
                mode: 'cors',
                headers: {
                    'Accept': 'text/html'
                }
            });
            
            if (!response.ok) {
                console.warn(`Failed to fetch: ${response.status}`);
                return null;
            }

            const html = await response.text();

            const patterns = [
                /<title>PyServeX\s+v([\d.]+)/i,
                /releases\/tag\/v([\d.]+)/,
                /aria-label="PyServeX\s+v([\d.]+)/i,
                /<h4[^>]*>.*?v([\d.]+).*?<\/h4>/i
            ];

            for (const pattern of patterns) {
                const match = html.match(pattern);
                if (match && match[1]) {
                    console.log(`✓ Version found: ${match[1]}`);
                    return match[1];
                }
            }
            
            console.warn('Version not found in HTML');
            return null;
            
        } catch (error) {
            console.warn('Fetch error:', error.message);
            return null;
        }
    }
    
    function getCachedVersion() {
        try {
            const cached = localStorage.getItem(CACHE_KEY);
            if (!cached) return null;
            
            const data = JSON.parse(cached);
            const now = Date.now();
            
            if (now - data.timestamp < CACHE_DURATION) {
                return data.version;
            }
            
            localStorage.removeItem(CACHE_KEY);
            return null;
        } catch (error) {
            console.error('Cache read error:', error);
            return null;
        }
    }

    function cacheVersion(version) {
        try {
            const data = {
                version: version,
                timestamp: Date.now()
            };
            localStorage.setItem(CACHE_KEY, JSON.stringify(data));
        } catch (error) {
            console.error('Cache write error:', error);
        }
    }

    function updateVersionDisplay(version) {
        const element = document.getElementById(VERSION_ELEMENT_ID);
        if (!element) {
            console.warn('Version element not found');
            return;
        }
        
        const versionLink = document.createElement('a');
        versionLink.href = 'https://git.pyserve.org/Shifty/pyserveX/releases/tag/v' + version;
        versionLink.textContent = version;
        versionLink.target = '_blank';
        versionLink.rel = 'noopener noreferrer';
        versionLink.className = 'version-link';
        
        element.innerHTML = '';
        element.appendChild(versionLink);
        
        const badge = document.createElement('span');
        badge.textContent = 'latest';
        badge.className = 'version-badge';
        badge.title = 'Fetched from Git repository';
        element.appendChild(document.createTextNode(' '));
        element.appendChild(badge);
        
        element.style.opacity = '1';
    }
    function showLoadingState() {
        const element = document.getElementById(VERSION_ELEMENT_ID);
        if (element) {
            element.style.opacity = '0.6';
        }
    }

    async function init() {
        showLoadingState();
        
        const cachedVersion = getCachedVersion();
        if (cachedVersion) {
            updateVersionDisplay(cachedVersion);
        }
        
        const latestVersion = await fetchLatestVersion();
        if (latestVersion) {
            cacheVersion(latestVersion);
            updateVersionDisplay(latestVersion);
        } else if (!cachedVersion) {
            const element = document.getElementById(VERSION_ELEMENT_ID);
            if (element) {
                element.textContent = FALLBACK_VERSION;
                element.style.opacity = '1';
                element.style.color = '#c9c9c9';
                element.title = 'Version fetch failed (CORS or network issue)';
            }
        }
    }
    
    if (document.readyState === 'loading') {
        document.addEventListener('DOMContentLoaded', init);
    } else {
        init();
    }
    
})();