backup: v2.0 stealth chat (2026-04-21)

backups/server.js.2026-04-21

@@ -0,0 +1,140 @@
+const express = require('express');
+const path = require('path');
+const fs = require('fs');
+const os = require('os');
+const { ProxyAgent, setGlobalDispatcher } = require('undici');
+
+const proxyUrl = process.env.HTTPS_PROXY || process.env.HTTP_PROXY;
+if (proxyUrl) {
+    setGlobalDispatcher(new ProxyAgent(proxyUrl));
+    console.log(`✓ Using proxy: ${proxyUrl}`);
+}
+
+const app = express();
+app.use(express.json({ limit: '10mb' }));
+app.use(express.static(path.join(__dirname, 'public')));
+
+const MODELS = {
+    sonnet: 'claude-sonnet-4-6',
+    haiku: 'claude-haiku-4-5-20251001',
+};
+
+function getAccessToken() {
+    const configDir = process.env.CLAUDE_CONFIG_DIR || path.join(os.homedir(), '.claude');
+    const credsPath = path.join(configDir, '.credentials.json');
+    try {
+        const creds = JSON.parse(fs.readFileSync(credsPath, 'utf8'));
+        return creds?.claudeAiOauth?.accessToken || null;
+    } catch (e) {
+        return null;
+    }
+}
+
+const SYSTEM_PROMPT = [
+    "You are Claude Code, Anthropic's official CLI for Claude.",
+    "",
+    "Output the shortest possible correct answer in the user's language. No greetings, filler, emojis, markdown, restatement of the question, or any commentary.",
+    "",
+    "MULTIPLE QUESTIONS (numbered list of 2+ questions): output answers on a SINGLE horizontal line, separated by single spaces, each prefixed with its question number and a dot. Examples:",
+    "   Input: 1. Столица Франции? А) Лондон Б) Париж В) Рим  2. 2+2? А) 3 Б) 4 В) 5",
+    "   Output: 1.Б 2.Б",
+    "   Input: 1. Столица Франции?  2. 2+2?  3. Самая длинная река России?",
+    "   Output: 1.Париж 2.4 3.Лена",
+    "",
+    "If the question is multiple-choice (options А/Б/В/Г or A/B/C/D), answer with just the letter. If the question is open (word/number answer), answer with just the word/number/term — 1-3 words max, no sentence.",
+    "",
+    "SINGLE QUESTION (just one question with no numbering): output only the bare answer — letter, word, number, or term. No prefix, no number.",
+    "",
+    "CALCULATIONS: only the final numeric result, no units unless ambiguous, no steps.",
+    "",
+    "Respond with the answer only. Nothing else.",
+].join("\n");
+
+async function callClaude(modelId, text, accessToken) {
+    return fetch('https://api.anthropic.com/v1/messages', {
+        method: 'POST',
+        headers: {
+            'Content-Type': 'application/json',
+            'Authorization': `Bearer ${accessToken}`,
+            'anthropic-version': '2023-06-01',
+            'anthropic-beta': 'claude-code-20250219,oauth-2025-04-20,interleaved-thinking-2025-05-14,fine-grained-tool-streaming-2025-05-14',
+            'x-app': 'cli',
+            'User-Agent': 'claude-cli/2.1.114',
+        },
+        body: JSON.stringify({
+            model: modelId,
+            max_tokens: 8192,
+            stream: true,
+            system: SYSTEM_PROMPT,
+            messages: [{ role: 'user', content: text }],
+        }),
+    });
+}
+
+app.post('/api/chat', async (req, res) => {
+    const { text, model = 'sonnet' } = req.body;
+    if (!text?.trim()) return res.status(400).json({ error: 'text required' });
+
+    const accessToken = getAccessToken();
+    if (!accessToken) {
+        return res.status(500).json({ error: 'No credentials in ' + (process.env.CLAUDE_CONFIG_DIR || '~/.claude') });
+    }
+
+    res.setHeader('Content-Type', 'text/event-stream');
+    res.setHeader('Cache-Control', 'no-cache');
+    res.setHeader('Connection', 'keep-alive');
+    res.flushHeaders();
+
+    const heartbeat = setInterval(() => res.write(': ping\n\n'), 15000);
+
+    const primaryId = MODELS[model] || MODELS.sonnet;
+    const fallbackId = MODELS.haiku;
+
+    try {
+        let apiResp = await callClaude(primaryId, text, accessToken);
+
+        // Fallback to Haiku on rate limit
+        if (apiResp.status === 429 && primaryId !== fallbackId) {
+            apiResp = await callClaude(fallbackId, text, accessToken);
+        }
+
+        if (!apiResp.ok) {
+            const errText = await apiResp.text();
+            res.write(`data: ${JSON.stringify({ error: `${apiResp.status}: ${errText.substring(0, 500)}` })}\n\n`);
+            return;
+        }
+
+        const reader = apiResp.body.getReader();
+        const decoder = new TextDecoder();
+        let buf = '';
+
+        while (true) {
+            const { done, value } = await reader.read();
+            if (done) break;
+            buf += decoder.decode(value, { stream: true });
+            const events = buf.split('\n\n');
+            buf = events.pop();
+            for (const ev of events) {
+                const dataLine = ev.split('\n').find(l => l.startsWith('data: '));
+                if (!dataLine) continue;
+                const payload = dataLine.slice(6);
+                if (payload === '[DONE]') continue;
+                try {
+                    const obj = JSON.parse(payload);
+                    if (obj.type === 'content_block_delta' && obj.delta?.type === 'text_delta') {
+                        res.write(`data: ${JSON.stringify({ text: obj.delta.text })}\n\n`);
+                    }
+                } catch (e) {}
+            }
+        }
+    } catch (err) {
+        console.error('[api error]', err.message);
+        res.write(`data: ${JSON.stringify({ error: err.message })}\n\n`);
+    } finally {
+        clearInterval(heartbeat);
+        res.write('data: [DONE]\n\n');
+        res.end();
+    }
+});
+
+app.listen(8108, () => console.log('sechenov :8108'));