fix: getChannel arg order, postImages via Nyxos /images/generations

generate.js: getChannel(userId, channelId) → getChannel(channelId, userId)
channels.js: getChannel alias → getFullChannel
postImages.js: убран /responses + gpt-5.5 (не работал на aiprimetech),
  заменён на Nyxos /images/generations с fallback на aiguoguo

src/routes/generate.js

@@ -50,7 +50,7 @@ router.post('/transform', async (req, res) => {
     if (!channelId || !originalPost || !action) {
       return res.status(400).json({ error: 'channelId, originalPost, action required' });
     }
-    const channel = await channelsSvc.getChannel(userId, channelId);
+    const channel = await channelsSvc.getChannel(channelId, userId);
     if (!channel) return res.status(404).json({ error: 'Channel not found' });
 
     const ai = require('../services/ai');
@@ -69,7 +69,7 @@ router.post('/post-image', async (req, res) => {
     const userId = parseInt(req.headers['x-user-id']) || null;
     if (!channelId || !post) return res.status(400).json({ error: 'channelId and post required' });
 
-    const channel = await channelsSvc.getChannel(userId, channelId);
+    const channel = await channelsSvc.getChannel(channelId, userId);
     if (!channel) return res.status(404).json({ error: 'Channel not found' });
 
     const { generatePostImage } = require('../services/postImages');
@@ -99,7 +99,7 @@ router.post('/topics-ideas', async (req, res) => {
     const { channelId, count = 7 } = req.body;
     const userId = parseInt(req.headers['x-user-id']) || null;
     if (!channelId) return res.status(400).json({ error: 'channelId required' });
-    const channel = await channelsSvc.getChannel(userId, channelId);
+    const channel = await channelsSvc.getChannel(channelId, userId);
     if (!channel) return res.status(404).json({ error: 'Channel not found' });
 
     const ai = require('../services/ai');
@@ -118,7 +118,7 @@ router.post('/from-url', async (req, res) => {
     const userId = parseInt(req.headers['x-user-id']) || null;
     if (!channelId || !url) return res.status(400).json({ error: 'channelId and url required' });
 
-    const channel = await channelsSvc.getChannel(userId, channelId);
+    const channel = await channelsSvc.getChannel(channelId, userId);
     if (!channel) return res.status(404).json({ error: 'Channel not found' });
 
     const { generateFromUrl } = require('../services/fromUrl');

src/services/channels.js

@@ -185,6 +185,7 @@ async function deleteChannel(channelId, userId) {
 }
 
 module.exports = {
+  getChannel: getFullChannel,   // алиас для обратной совместимости
   getFullChannel,
   listChannels,
   createChannel,

src/services/postImages.js

@@ -85,61 +85,46 @@ ${style.image_prompt_instructions ? `\nChannel visual guidelines: ${style.image_
 Composition: 16:9 wide format, balanced, suitable for social media.
 Strictly: no text, no letters, no logos, no faces of real people.`;
 
-  const model = config.ai.imageModelViaResponses || 'gpt-5.2';
-  const wrappedInput = `Use the image_generation tool to create the following illustration. Do not write any text response, only call the tool.\n\n${prompt}`;
+  // Используем Nyxos /images/generations (первичный провайдер)
+  // с fallback на aiguoguo — тот же путь что для обложек статей
+  const model = config.ai.imageModel || 'gpt-image-2';
 
-  const started = Date.now();
-  let res;
-  try {
-    res = await axios.post(
-      `${config.ai.baseUrl}/responses`,
-      {
-        model,
-        input: wrappedInput,
-        tools: [{ type: 'image_generation' }],
-        tool_choice: { type: 'image_generation' },
-      },
-      {
-        headers: { Authorization: `Bearer ${config.ai.apiKey}` },
-        timeout: 300_000,
+  async function tryProvider(baseUrl, apiKey) {
+    const started = Date.now();
+    try {
+      const res = await axios.post(
+        `${baseUrl}/images/generations`,
+        { model, prompt: prompt.slice(0, 4000), n: 1, size: '1024x1024', response_format: 'url' },
+        { headers: { Authorization: `Bearer ${apiKey}` }, timeout: 120_000 }
+      );
+      const item = res.data?.data?.[0];
+      if (!item) throw new Error('No image data');
+      aiUsage.log({ provider: aiUsage.providerFromBaseUrl(baseUrl), requestType: 'image', model, imageCount: 1, meta: { channel_id: channel.id }, succeeded: true }).catch(() => {});
+      if (item.url) {
+        const r = await axios.get(item.url, { responseType: 'arraybuffer', timeout: 60_000 });
+        return Buffer.from(r.data);
       }
-    );
+      if (item.b64_json) return Buffer.from(item.b64_json, 'base64');
+      throw new Error('No url or b64_json');
+    } catch (err) {
+      aiUsage.log({ provider: aiUsage.providerFromBaseUrl(baseUrl), requestType: 'image', model, imageCount: 1, meta: { channel_id: channel.id }, succeeded: false, errorMessage: (err.response?.data?.error?.message || err.message || '').slice(0, 500) }).catch(() => {});
+      throw err;
+    }
+  }
+
+  let bytes;
+  try {
+    bytes = await tryProvider(config.ai.imageBaseUrl, config.ai.imageApiKey);
   } catch (err) {
-    aiUsage.log({
-      provider: aiUsage.providerFromBaseUrl(config.ai.baseUrl),
-      requestType: 'image_via_responses',
-      model, imageCount: 1,
-      meta: { channel_id: channel.id },
-      durationMs: Date.now() - started, succeeded: false,
-      errorMessage: (err.response?.data?.error?.message || err.message || '').slice(0, 500),
-    }).catch(() => {});
-    throw err;
+    const status = err.response?.status;
+    if (!status || status >= 500) {
+      console.warn('[postImages] primary failed, trying fallback...');
+      bytes = await tryProvider(config.ai.imageFallbackBaseUrl, config.ai.imageFallbackApiKey);
+    } else { throw err; }
   }
 
-  const output = res.data?.output || [];
-  const imgCall = output.find(o => o.type === 'image_generation_call');
-  if (!imgCall?.result) {
-    aiUsage.log({
-      provider: aiUsage.providerFromBaseUrl(config.ai.baseUrl),
-      requestType: 'image_via_responses', model, imageCount: 1,
-      meta: { channel_id: channel.id },
-      durationMs: Date.now() - started, succeeded: false,
-      errorMessage: 'No image generated',
-    }).catch(() => {});
-    throw new Error('No image generated');
-  }
-
-  aiUsage.log({
-    provider: aiUsage.providerFromBaseUrl(config.ai.baseUrl),
-    requestType: 'image_via_responses', model, imageCount: 1,
-    requestId: res.data?.id,
-    meta: { channel_id: channel.id },
-    durationMs: Date.now() - started, succeeded: true,
-  }).catch(() => {});
-
-  const bytes = Buffer.from(imgCall.result, 'base64');
   const tsKey = `post-${channel.id}-${Date.now()}`;
-  const ext = imgCall.output_format || 'png';
+  const ext = 'png';
 
   // Оптимизация через sharp если есть
   let publicUrl;