v2.3.1: CDN redirect gateway, fix token username bug

- Migrate patch downloads to auth server redirect gateway (302 -> CDN)
  Allows instant CDN switching via admin panel without launcher update
- Fix identity token "Player" username mismatch on fresh install
  Add token username verification with retry in fetchAuthTokens
- Refactor versionManager to use mirror manifest via auth.sanasol.ws/patches
- Add optimal patch routing (BFS) for differential updates
- Add PATCH_CDN_INFRASTRUCTURE.md documentation

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

backend/services/versionManager.js

@@ -2,186 +2,240 @@ const axios = require('axios');
 const crypto = require('crypto');
 const fs = require('fs');
 const { getOS, getArch } = require('../utils/platformUtils');
-const { smartRequest } = require('../utils/proxyClient');
 
-const BASE_PATCH_URL = 'https://game-patches.hytale.com/patches';
-const MANIFEST_API = 'https://files.hytalef2p.com/api/patch_manifest';
-const NEW_API_URL = 'https://thecute.cloud/ShipOfYarn/api.php';
+// Patches CDN via auth server redirect gateway (allows instant CDN switching)
+const AUTH_DOMAIN = process.env.HYTALE_AUTH_DOMAIN || 'auth.sanasol.ws';
+const MIRROR_BASE_URL = `https://${AUTH_DOMAIN}/patches`;
+const MIRROR_MANIFEST_URL = `${MIRROR_BASE_URL}/manifest.json`;
 
-let apiCache = null;
-let apiCacheTime = 0;
-const API_CACHE_DURATION = 60000; // 1 minute
+// Fallback: latest known build number if manifest is unreachable
+const FALLBACK_LATEST_BUILD = 11;
 
-async function fetchNewAPI() {
+let manifestCache = null;
+let manifestCacheTime = 0;
+const MANIFEST_CACHE_DURATION = 60000; // 1 minute
+
+/**
+ * Fetch the mirror manifest from MEGA S4
+ */
+async function fetchMirrorManifest() {
   const now = Date.now();
-  
-  if (apiCache && (now - apiCacheTime) < API_CACHE_DURATION) {
-    console.log('[NewAPI] Using cached API data');
-    return apiCache;
+
+  if (manifestCache && (now - manifestCacheTime) < MANIFEST_CACHE_DURATION) {
+    console.log('[Mirror] Using cached manifest');
+    return manifestCache;
   }
-  
+
   try {
-    console.log('[NewAPI] Fetching from:', NEW_API_URL);
-    const response = await axios.get(NEW_API_URL, {
+    console.log('[Mirror] Fetching manifest from:', MIRROR_MANIFEST_URL);
+    const response = await axios.get(MIRROR_MANIFEST_URL, {
       timeout: 15000,
-      headers: {
-        'User-Agent': 'Hytale-F2P-Launcher'
-      }
+      headers: { 'User-Agent': 'Hytale-F2P-Launcher' }
     });
-    
-    if (response.data && response.data.hytale) {
-      apiCache = response.data;
-      apiCacheTime = now;
-      console.log('[NewAPI] API data fetched and cached successfully');
+
+    if (response.data && response.data.files) {
+      manifestCache = response.data;
+      manifestCacheTime = now;
+      console.log('[Mirror] Manifest fetched successfully');
       return response.data;
-    } else {
-      throw new Error('Invalid API response structure');
     }
+    throw new Error('Invalid manifest structure');
   } catch (error) {
-    console.error('[NewAPI] Error fetching API:', error.message);
-    if (apiCache) {
-      console.log('[NewAPI] Using expired cache due to error');
-      return apiCache;
+    console.error('[Mirror] Error fetching manifest:', error.message);
+    if (manifestCache) {
+      console.log('[Mirror] Using expired cache');
+      return manifestCache;
     }
     throw error;
   }
 }
 
-async function getLatestVersionFromNewAPI(branch = 'release') {
-  try {
-    const apiData = await fetchNewAPI();
-    const osName = getOS();
-    const arch = getArch();
-    
-    let osKey = osName;
-    if (osName === 'darwin') {
-      osKey = 'mac';
+/**
+ * Parse manifest to get available patches for current platform
+ * Returns array of { from, to, key, size }
+ */
+function getPlatformPatches(manifest, branch = 'release') {
+  const os = getOS();
+  const arch = getArch();
+  const prefix = `${os}/${arch}/${branch}/`;
+  const patches = [];
+
+  for (const [key, info] of Object.entries(manifest.files)) {
+    if (key.startsWith(prefix) && key.endsWith('.pwr')) {
+      const filename = key.slice(prefix.length, -4); // e.g., "0_to_11"
+      const match = filename.match(/^(\d+)_to_(\d+)$/);
+      if (match) {
+        patches.push({
+          from: parseInt(match[1]),
+          to: parseInt(match[2]),
+          key,
+          size: info.size
+        });
+      }
     }
-    
-    const branchData = apiData.hytale[branch];
-    if (!branchData || !branchData[osKey]) {
-      throw new Error(`No data found for branch: ${branch}, OS: ${osKey}`);
-    }
-    
-    const osData = branchData[osKey];
-    
-    const versions = Object.keys(osData).filter(key => key.endsWith('.pwr'));
-    
-    if (versions.length === 0) {
-      throw new Error(`No .pwr files found for ${osKey}`);
-    }
-    
-    const versionNumbers = versions.map(v => {
-      const match = v.match(/v(\d+)/);
-      return match ? parseInt(match[1]) : 0;
-    });
-    
-    const latestVersionNumber = Math.max(...versionNumbers);
-    console.log(`[NewAPI] Latest version number: ${latestVersionNumber} for branch ${branch}`);
-    
-    return `v${latestVersionNumber}`;
-  } catch (error) {
-    console.error('[NewAPI] Error getting latest version:', error.message);
-    throw error;
   }
+
+  return patches;
 }
 
-async function getPWRUrlFromNewAPI(branch = 'release', version = 'v8') {
-  try {
-    const apiData = await fetchNewAPI();
-    const osName = getOS();
-    const arch = getArch();
-    
-    let osKey = osName;
-    if (osName === 'darwin') {
-      osKey = 'mac';
-    }
-    
-    let fileName;
-    if (osName === 'windows') {
-      fileName = `${version}-windows-amd64.pwr`;
-    } else if (osName === 'linux') {
-      fileName = `${version}-linux-amd64.pwr`;
-    } else if (osName === 'darwin') {
-      fileName = `${version}-darwin-arm64.pwr`;
-    }
-    
-    const branchData = apiData.hytale[branch];
-    if (!branchData || !branchData[osKey]) {
-      throw new Error(`No data found for branch: ${branch}, OS: ${osKey}`);
-    }
-    
-    const osData = branchData[osKey];
-    const url = osData[fileName];
-    
-    if (!url) {
-      throw new Error(`No URL found for ${fileName}`);
-    }
-    
-    console.log(`[NewAPI] URL for ${fileName}: ${url}`);
-    return url;
-  } catch (error) {
-    console.error('[NewAPI] Error getting PWR URL:', error.message);
-    throw error;
+/**
+ * Find optimal patch path using BFS with download size minimization
+ * Returns array of { from, to, url, size, key } steps, or null if no path found
+ */
+function findOptimalPatchPath(currentBuild, targetBuild, patches) {
+  if (currentBuild >= targetBuild) return [];
+
+  const edges = {};
+  for (const patch of patches) {
+    if (!edges[patch.from]) edges[patch.from] = [];
+    edges[patch.from].push(patch);
   }
+
+  const queue = [{ build: currentBuild, path: [], totalSize: 0 }];
+  let bestPath = null;
+  let bestSize = Infinity;
+
+  while (queue.length > 0) {
+    const { build, path, totalSize } = queue.shift();
+
+    if (build === targetBuild) {
+      if (totalSize < bestSize) {
+        bestPath = path;
+        bestSize = totalSize;
+      }
+      continue;
+    }
+
+    if (totalSize >= bestSize) continue;
+
+    const nextEdges = edges[build] || [];
+    for (const edge of nextEdges) {
+      if (edge.to <= build || edge.to > targetBuild) continue;
+      if (path.some(p => p.to === edge.to)) continue;
+
+      queue.push({
+        build: edge.to,
+        path: [...path, {
+          from: edge.from,
+          to: edge.to,
+          url: `${MIRROR_BASE_URL}/${edge.key}`,
+          size: edge.size,
+          key: edge.key
+        }],
+        totalSize: totalSize + edge.size
+      });
+    }
+  }
+
+  return bestPath;
+}
+
+/**
+ * Get the optimal update plan from currentBuild to targetBuild
+ * Returns { steps: [{from, to, url, size}], totalSize, isFullInstall }
+ */
+async function getUpdatePlan(currentBuild, targetBuild, branch = 'release') {
+  const manifest = await fetchMirrorManifest();
+  const patches = getPlatformPatches(manifest, branch);
+
+  // Try optimal path
+  const steps = findOptimalPatchPath(currentBuild, targetBuild, patches);
+
+  if (steps && steps.length > 0) {
+    const totalSize = steps.reduce((sum, s) => sum + s.size, 0);
+    console.log(`[Mirror] Update plan: ${steps.map(s => `${s.from}\u2192${s.to}`).join(' + ')} (${(totalSize / 1024 / 1024).toFixed(0)} MB)`);
+    return { steps, totalSize, isFullInstall: steps.length === 1 && steps[0].from === 0 };
+  }
+
+  // Fallback: full install 0 -> target
+  const fullPatch = patches.find(p => p.from === 0 && p.to === targetBuild);
+  if (fullPatch) {
+    const step = {
+      from: 0,
+      to: targetBuild,
+      url: `${MIRROR_BASE_URL}/${fullPatch.key}`,
+      size: fullPatch.size,
+      key: fullPatch.key
+    };
+    console.log(`[Mirror] Full install: 0\u2192${targetBuild} (${(fullPatch.size / 1024 / 1024).toFixed(0)} MB)`);
+    return { steps: [step], totalSize: fullPatch.size, isFullInstall: true };
+  }
+
+  throw new Error(`No patch path found from build ${currentBuild} to ${targetBuild} for ${getOS()}/${getArch()}`);
 }
 
 async function getLatestClientVersion(branch = 'release') {
   try {
-    console.log(`[NewAPI] Fetching latest client version from new API (branch: ${branch})...`);
-    
-    // Utiliser la nouvelle API
-    const latestVersion = await getLatestVersionFromNewAPI(branch);
-    console.log(`[NewAPI] Latest client version for ${branch}: ${latestVersion}`);
-    return latestVersion;
-    
-  } catch (error) {
-    console.error('[NewAPI] Error fetching client version from new API:', error.message);
-    console.log('[NewAPI] Falling back to old API...');
-    
-    // Fallback vers l'ancienne API si la nouvelle échoue
-    try {
-      const response = await smartRequest(`https://files.hytalef2p.com/api/version_client?branch=${branch}`, {
-        timeout: 40000,
-        headers: {
-          'User-Agent': 'Hytale-F2P-Launcher'
-        }
-      });
+    console.log(`[Mirror] Fetching latest client version (branch: ${branch})...`);
+    const manifest = await fetchMirrorManifest();
+    const patches = getPlatformPatches(manifest, branch);
 
-      if (response.data && response.data.client_version) {
-        const version = response.data.client_version;
-        console.log(`Latest client version for ${branch} (old API): ${version}`);
-        return version;
-      } else {
-        console.log('Warning: Invalid API response, falling back to latest known version (v8)');
-        return 'v8';
-      }
-    } catch (fallbackError) {
-      console.error('Error fetching client version from old API:', fallbackError.message);
-      console.log('Warning: Both APIs unavailable, falling back to latest known version (v8)');
-      return 'v8';
+    if (patches.length === 0) {
+      console.log(`[Mirror] No patches for branch '${branch}', using fallback`);
+      return `v${FALLBACK_LATEST_BUILD}`;
     }
+
+    const latestBuild = Math.max(...patches.map(p => p.to));
+    console.log(`[Mirror] Latest client version: v${latestBuild}`);
+    return `v${latestBuild}`;
+  } catch (error) {
+    console.error('[Mirror] Error:', error.message);
+    return `v${FALLBACK_LATEST_BUILD}`;
   }
 }
 
-// Fonction utilitaire pour extraire le numéro de version
-// Supporte les formats: "7.pwr", "v8", "v8-windows-amd64.pwr", etc.
+/**
+ * Get PWR download URL for fresh install (0 -> target)
+ * Backward-compatible with old getPWRUrlFromNewAPI signature
+ * Checks mirror first, then constructs URL for the branch
+ */
+async function getPWRUrl(branch = 'release', version = 'v11') {
+  const targetBuild = extractVersionNumber(version);
+  const os = getOS();
+  const arch = getArch();
+
+  try {
+    const manifest = await fetchMirrorManifest();
+    const patches = getPlatformPatches(manifest, branch);
+    const fullPatch = patches.find(p => p.from === 0 && p.to === targetBuild);
+
+    if (fullPatch) {
+      const url = `${MIRROR_BASE_URL}/${fullPatch.key}`;
+      console.log(`[Mirror] PWR URL: ${url}`);
+      return url;
+    }
+
+    if (patches.length > 0) {
+      // Branch exists in mirror but no full patch for this target - construct URL
+      console.log(`[Mirror] No 0->${targetBuild} patch found, constructing URL`);
+    } else {
+      console.log(`[Mirror] Branch '${branch}' not in mirror, constructing URL`);
+    }
+  } catch (error) {
+    console.error('[Mirror] Error getting PWR URL:', error.message);
+  }
+
+  // Construct mirror URL (will work if patch was uploaded but manifest is stale)
+  return `${MIRROR_BASE_URL}/${os}/${arch}/${branch}/0_to_${targetBuild}.pwr`;
+}
+
+// Backward-compatible alias
+const getPWRUrlFromNewAPI = getPWRUrl;
+
+// Utility function to extract version number
+// Supports: "7.pwr", "v8", "v8-windows-amd64.pwr", "5_to_10", etc.
 function extractVersionNumber(version) {
   if (!version) return 0;
-  
-  // Nouveau format: "v8" ou "v8-xxx.pwr"
+
+  // New format: "v8" or "v8-xxx.pwr"
   const vMatch = version.match(/v(\d+)/);
-  if (vMatch) {
-    return parseInt(vMatch[1]);
-  }
-  
-  // Ancien format: "7.pwr"
+  if (vMatch) return parseInt(vMatch[1]);
+
+  // Old format: "7.pwr"
   const pwrMatch = version.match(/(\d+)\.pwr/);
-  if (pwrMatch) {
-    return parseInt(pwrMatch[1]);
-  }
-  
-  // Fallback: essayer de parser directement
+  if (pwrMatch) return parseInt(pwrMatch[1]);
+
+  // Fallback
   const num = parseInt(version);
   return isNaN(num) ? 0 : num;
 }
@@ -189,7 +243,7 @@ function extractVersionNumber(version) {
 function buildArchiveUrl(buildNumber, branch = 'release') {
   const os = getOS();
   const arch = getArch();
-  return `${BASE_PATCH_URL}/${os}/${arch}/${branch}/0/${buildNumber}.pwr`;
+  return `${MIRROR_BASE_URL}/${os}/${arch}/${branch}/0_to_${buildNumber}.pwr`;
 }
 
 async function checkArchiveExists(buildNumber, branch = 'release') {
@@ -197,91 +251,56 @@ async function checkArchiveExists(buildNumber, branch = 'release') {
   try {
     const response = await axios.head(url, { timeout: 10000 });
     return response.status === 200;
-  } catch (error) {
+  } catch {
     return false;
   }
 }
 
-async function discoverAvailableVersions(latestKnown, branch = 'release', maxProbe = 50) {
-  const available = [];
-  const latest = extractVersionNumber(latestKnown);
-  
-  for (let i = latest; i >= Math.max(1, latest - maxProbe); i--) {
-    const exists = await checkArchiveExists(i, branch);
-    if (exists) {
-      available.push(`${i}.pwr`);
-    }
-  }
-  
-  return available;
-}
-
-async function fetchPatchManifest(branch = 'release') {
+async function discoverAvailableVersions(latestKnown, branch = 'release') {
   try {
-    const os = getOS();
-    const arch = getArch();
-    const response = await smartRequest(`${MANIFEST_API}?branch=${branch}&os=${os}&arch=${arch}`, {
-      timeout: 10000
-    });
-    return response.data.patches || {};
-  } catch (error) {
-    console.error('Failed to fetch patch manifest:', error.message);
-    return {};
+    const manifest = await fetchMirrorManifest();
+    const patches = getPlatformPatches(manifest, branch);
+    const versions = [...new Set(patches.map(p => p.to))].sort((a, b) => b - a);
+    return versions.map(v => `${v}.pwr`);
+  } catch {
+    return [];
   }
 }
 
 async function extractVersionDetails(targetVersion, branch = 'release') {
   const buildNumber = extractVersionNumber(targetVersion);
-  const previousBuild = buildNumber - 1;
-  
-  const manifest = await fetchPatchManifest(branch);
-  const patchInfo = manifest[buildNumber];
-  
+  const fullUrl = buildArchiveUrl(buildNumber, branch);
+
   return {
     version: targetVersion,
-    buildNumber: buildNumber,
+    buildNumber,
     buildName: `HYTALE-Build-${buildNumber}`,
-    fullUrl: patchInfo?.original_url || buildArchiveUrl(buildNumber, branch),
-    differentialUrl: patchInfo?.patch_url || null,
-    checksum: patchInfo?.patch_hash || null,
-    sourceVersion: patchInfo?.from ? `${patchInfo.from}.pwr` : (previousBuild > 0 ? `${previousBuild}.pwr` : null),
-    isDifferential: !!patchInfo?.proper_patch,
-    releaseNotes: patchInfo?.patch_note || null
+    fullUrl,
+    differentialUrl: null,
+    checksum: null,
+    sourceVersion: null,
+    isDifferential: false,
+    releaseNotes: null
   };
 }
 
-function canUseDifferentialUpdate(currentVersion, targetDetails) {
-  if (!targetDetails) return false;
-  if (!targetDetails.differentialUrl) return false;
-  if (!targetDetails.isDifferential) return false;
-  
-  if (!currentVersion) return false;
-  
-  const currentBuild = extractVersionNumber(currentVersion);
-  const expectedSource = extractVersionNumber(targetDetails.sourceVersion);
-  
-  return currentBuild === expectedSource;
+function canUseDifferentialUpdate() {
+  // Differential updates are now handled via getUpdatePlan()
+  return false;
 }
 
 function needsIntermediatePatches(currentVersion, targetVersion) {
   if (!currentVersion) return [];
-  
   const current = extractVersionNumber(currentVersion);
   const target = extractVersionNumber(targetVersion);
-  
-  const intermediates = [];
-  for (let i = current + 1; i <= target; i++) {
-    intermediates.push(`${i}.pwr`);
-  }
-  
-  return intermediates;
+  if (current >= target) return [];
+  return [targetVersion];
 }
 
 async function computeFileChecksum(filePath) {
   return new Promise((resolve, reject) => {
     const hash = crypto.createHash('sha256');
     const stream = fs.createReadStream(filePath);
-    
     stream.on('data', data => hash.update(data));
     stream.on('end', () => resolve(hash.digest('hex')));
     stream.on('error', reject);
@@ -290,7 +309,6 @@ async function computeFileChecksum(filePath) {
 
 async function validateChecksum(filePath, expectedChecksum) {
   if (!expectedChecksum) return true;
-  
   const actualChecksum = await computeFileChecksum(filePath);
   return actualChecksum === expectedChecksum;
 }
@@ -299,7 +317,7 @@ function getInstalledClientVersion() {
   try {
     const { loadVersionClient } = require('../core/config');
     return loadVersionClient();
-  } catch (err) {
+  } catch {
     return null;
   }
 }
@@ -315,8 +333,12 @@ module.exports = {
   computeFileChecksum,
   validateChecksum,
   getInstalledClientVersion,
-  fetchNewAPI,
-  getLatestVersionFromNewAPI,
+  fetchMirrorManifest,
+  getPWRUrl,
   getPWRUrlFromNewAPI,
-  extractVersionNumber
+  getUpdatePlan,
+  extractVersionNumber,
+  getPlatformPatches,
+  findOptimalPatchPath,
+  MIRROR_BASE_URL
 };