<?php
/**
 * wv_llm() — Sovereign LLM cascade for WEVIA Master intents
 * Cascade: Groq → Cerebras → Mistral → Ollama local (0€)
 */
function wv_llm($prompt, $system = "Tu es WEVIA, IA souveraine de WEVAL Consulting.") {
    static $keys = null;
    if (!$keys) {
        $env = @file_get_contents("/etc/weval/secrets.env");
        $keys = [];
        if (preg_match("/GROQ_KEY=(.+)/", $env, $m)) $keys["groq"] = trim($m[1]);
        if (preg_match("/CEREBRAS_API_KEY=(.+)/", $env, $m)) $keys["cerebras"] = trim($m[1]);
        if (preg_match("/MISTRAL_KEY=(.+)/", $env, $m)) $keys["mistral"] = trim($m[1]);
    }
    $msgs = [["role" => "system", "content" => $system], ["role" => "user", "content" => $prompt]];
    
    // CASCADE: try each provider
    $providers = [
        ["url" => "https://api.groq.com/openai/v1/chat/completions", "key" => $keys["groq"] ?? "", "model" => "llama-3.3-70b-versatile", "name" => "groq"],
        ["url" => "https://api.cerebras.ai/v1/chat/completions", "key" => $keys["cerebras"] ?? "", "model" => "llama3.1-8b", "name" => "cerebras"],
        ["url" => "https://api.mistral.ai/v1/chat/completions", "key" => $keys["mistral"] ?? "", "model" => "open-mistral-7b", "name" => "mistral"],
        ["url" => "http://127.0.0.1:11435/api/chat", "key" => "", "model" => "qwen3:4b", "name" => "ollama"]
    ];
    
    foreach ($providers as $p) {
        if (!$p["key"] && $p["name"] !== "ollama") continue;
        
        if ($p["name"] === "ollama") {
            // Ollama uses different format
            $data = json_encode(["model" => $p["model"], "messages" => $msgs, "stream" => false]);
            $headers = ["Content-Type: application/json"];
        } else {
            $data = json_encode(["model" => $p["model"], "messages" => $msgs, "max_tokens" => 1500]);
            $headers = ["Content-Type: application/json", "Authorization: Bearer " . $p["key"]];
        }
        
        $ch = curl_init($p["url"]);
        curl_setopt_array($ch, [
            CURLOPT_RETURNTRANSFER => true,
            CURLOPT_POST => true,
            CURLOPT_POSTFIELDS => $data,
            CURLOPT_HTTPHEADER => $headers,
            CURLOPT_TIMEOUT => 20,
            CURLOPT_SSL_VERIFYPEER => false
        ]);
        $r = curl_exec($ch);
        $code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        curl_close($ch);
        
        if ($code === 200) {
            $d = @json_decode($r, true);
            $content = $d["choices"][0]["message"]["content"] ?? ($d["message"]["content"] ?? null);
            if ($content) return $content;
        }
        // 429 or error → try next provider
    }
    return "LLM cascade: tous les providers occupes";
}