<?php
/**
 * WEVAL CONSENSUS ENGINE v1.0 — Multi-IA Consensus with Discovery
 * 
 * ARCHITECTURE:
 * 1. Reçoit une question
 * 2. Query 5+ providers en PARALLÈLE (curl_multi)
 * 3. Collecte toutes les réponses
 * 4. Meta-provider synthétise le CONSENSUS
 * 5. IA Discovery: auto-détecte nouveaux providers gratuits
 * 
 * PROVIDERS (15 wirés):
 * GRATUITS: Cerebras 235B, Groq 70B, Kimi-K2, NVIDIA 70B, Mistral Large,
 *           SambaNova DeepSeek, Together, Cohere, DeepSeek, OpenRouter
 * SOUVERAINS: Ollama brain-v3 (local), Gemini Flash
 * PAYANTS: Anthropic Claude, OpenAI GPT-4o (fallback only)
 */

header('Content-Type: application/json');
header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Headers: Content-Type');

// Load secrets
$secrets = [];
foreach (explode("\n", @file_get_contents("/etc/weval/secrets.env") ?: '') as $line) {
    $line = trim($line);
    if ($line && !str_starts_with($line, '#') && str_contains($line, '=')) {
        [$k, $v] = explode('=', $line, 2);
        $secrets[trim($k)] = trim($v);
    }
}

// ═══ ALL PROVIDERS ═══
$ALL_PROVIDERS = [
    // TIER 0 — Souverains (gratuits, ultra-rapides)
    ['name'=>'cerebras', 'tier'=>0, 'model'=>'qwen-3-235b-a22b-instruct-2507', 'url'=>'https://api.cerebras.ai/v1/chat/completions', 'key_name'=>'CEREBRAS_API_KEY', 'params'=>235],
    ['name'=>'groq', 'tier'=>0, 'model'=>'llama-3.3-70b-versatile', 'url'=>'https://api.groq.com/openai/v1/chat/completions', 'key_name'=>'GROQ_KEY', 'params'=>70],
    ['name'=>'kimi-k2', 'tier'=>0, 'model'=>'moonshotai/kimi-k2-instruct', 'url'=>'https://api.groq.com/openai/v1/chat/completions', 'key_name'=>'GROQ_KEY', 'params'=>1000],
    ['name'=>'sambanova', 'tier'=>0, 'model'=>'DeepSeek-V3.2', 'url'=>'https://api.sambanova.ai/v1/chat/completions', 'key_name'=>'SAMBANOVA_KEY', 'params'=>671],
    
    // TIER 1 — Gratuits rate-limited
    ['name'=>'nvidia', 'tier'=>1, 'model'=>'meta/llama-3.3-70b-instruct', 'url'=>'https://integrate.api.nvidia.com/v1/chat/completions', 'key_name'=>'NVIDIA_NIM_KEY', 'params'=>70],
    ['name'=>'mistral', 'tier'=>1, 'model'=>'mistral-large-latest', 'url'=>'https://api.mistral.ai/v1/chat/completions', 'key_name'=>'MISTRAL_KEY', 'params'=>123],
    ['name'=>'together', 'tier'=>1, 'model'=>'meta-llama/Meta-Llama-3.1-70B-Instruct-Turbo', 'url'=>'https://api.together.xyz/v1/chat/completions', 'key_name'=>'TOGETHER_KEY', 'params'=>70],
    ['name'=>'cohere', 'tier'=>1, 'model'=>'command-r-plus', 'url'=>'https://api.cohere.ai/v1/chat', 'key_name'=>'COHERE_KEY', 'params'=>104, 'format'=>'cohere'],
    ['name'=>'deepseek', 'tier'=>1, 'model'=>'deepseek-chat', 'url'=>'https://api.deepseek.com/v1/chat/completions', 'key_name'=>'DEEPSEEK_KEY', 'params'=>671],
    ['name'=>'openrouter', 'tier'=>1, 'model'=>'meta-llama/llama-3.3-70b-instruct:free', 'url'=>'https://openrouter.ai/api/v1/chat/completions', 'key_name'=>'OPENROUTER_KEY', 'params'=>70],
    
    // TIER 2 — Souverains + Payants
    ['name'=>'gemini', 'tier'=>2, 'model'=>'gemini-2.5-flash', 'url'=>'https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash:generateContent', 'key_name'=>'GEMINI_KEY', 'params'=>'?', 'format'=>'gemini'],
    ['name'=>'alibaba', 'tier'=>2, 'model'=>'qwen-turbo', 'url'=>'https://dashscope-intl.aliyuncs.com/compatible-mode/v1/chat/completions', 'key_name'=>'ALIBABA_KEY', 'params'=>72],
    ['name'=>'zhipu', 'tier'=>2, 'model'=>'glm-4-flash', 'url'=>'https://open.bigmodel.cn/api/paas/v4/chat/completions', 'key_name'=>'ZHIPU_KEY', 'params'=>130],
    
    // TIER 3 — Local souverain
    ['name'=>'ollama', 'tier'=>3, 'model'=>'weval-brain-v3', 'url'=>'http://127.0.0.1:11434/v1/chat/completions', 'key_name'=>'', 'params'=>8],
];

// ═══ FUNCTIONS ═══

function call_provider($provider, $prompt, $secrets, $timeout = 15) {
    $key = $provider['key_name'] ? ($secrets[$provider['key_name']] ?? '') : 'local';
    if (!$key && $provider['name'] !== 'ollama') return null;
    
    $format = $provider['format'] ?? 'openai';
    
    if ($format === 'cohere') {
        $body = json_encode(['message' => $prompt, 'model' => $provider['model']]);
        $authHeader = "Authorization: Bearer $key";
    } elseif ($format === 'gemini') {
        $url = $provider['url'] . "?key=$key";
        $body = json_encode(['contents' => [['parts' => [['text' => $prompt]]]]]);
        $ch = curl_init($url);
        curl_setopt_array($ch, [CURLOPT_POST => true, CURLOPT_POSTFIELDS => $body,
            CURLOPT_HTTPHEADER => ['Content-Type: application/json'],
            CURLOPT_RETURNTRANSFER => true, CURLOPT_TIMEOUT => $timeout, CURLOPT_SSL_VERIFYPEER => false]);
        $resp = curl_exec($ch);
        $code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        curl_close($ch);
        if ($code >= 200 && $code < 300) {
            $d = json_decode($resp, true);
            return $d['candidates'][0]['content']['parts'][0]['text'] ?? null;
        }
        return null;
    } else {
        $body = json_encode([
            'model' => $provider['model'],
            'messages' => [['role' => 'user', 'content' => $prompt]],
            'max_tokens' => 300, 'temperature' => 0.3
        ]);
        $authHeader = "Authorization: Bearer $key";
    }
    
    $ch = curl_init($provider['url']);
    curl_setopt_array($ch, [CURLOPT_POST => true, CURLOPT_POSTFIELDS => $body,
        CURLOPT_HTTPHEADER => ['Content-Type: application/json', $authHeader],
        CURLOPT_RETURNTRANSFER => true, CURLOPT_TIMEOUT => $timeout, CURLOPT_SSL_VERIFYPEER => false]);
    $resp = curl_exec($ch);
    $code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    $latency = round(curl_getinfo($ch, CURLINFO_TOTAL_TIME) * 1000);
    curl_close($ch);
    
    if ($code >= 200 && $code < 300) {
        $d = json_decode($resp, true);
        if ($format === 'cohere') return $d['text'] ?? null;
        return $d['choices'][0]['message']['content'] ?? null;
    }
    return null;
}

function consensus_parallel($prompt, $providers, $secrets, $max_providers = 5) {
    $results = [];
    $mh = curl_multi_init();
    $handles = [];
    $count = 0;
    
    foreach ($providers as $p) {
        if ($count >= $max_providers) break;
        $key = $p['key_name'] ? ($secrets[$p['key_name']] ?? '') : 'local';
        if (!$key && $p['name'] !== 'ollama') continue;
        
        $format = $p['format'] ?? 'openai';
        if ($format === 'gemini') {
            $url = $p['url'] . "?key=$key";
            $body = json_encode(['contents' => [['parts' => [['text' => $prompt]]]]]);
            $headers = ['Content-Type: application/json'];
        } elseif ($format === 'cohere') {
            $url = $p['url'];
            $body = json_encode(['message' => $prompt, 'model' => $p['model']]);
            $headers = ['Content-Type: application/json', "Authorization: Bearer $key"];
        } else {
            $url = $p['url'];
            $body = json_encode(['model' => $p['model'], 'messages' => [['role' => 'user', 'content' => $prompt]], 'max_tokens' => 300, 'temperature' => 0.3]);
            $headers = ['Content-Type: application/json', "Authorization: Bearer $key"];
        }
        
        $ch = curl_init($url);
        curl_setopt_array($ch, [CURLOPT_POST => true, CURLOPT_POSTFIELDS => $body,
            CURLOPT_HTTPHEADER => $headers, CURLOPT_RETURNTRANSFER => true,
            CURLOPT_TIMEOUT => 15, CURLOPT_SSL_VERIFYPEER => false]);
        curl_multi_add_handle($mh, $ch);
        $handles[] = ['ch' => $ch, 'provider' => $p, 'format' => $format];
        $count++;
    }
    
    // Execute parallel
    do { $status = curl_multi_exec($mh, $active); } while ($status === CURLM_CALL_MULTI_PERFORM);
    while ($active && $status === CURLM_OK) {
        curl_multi_select($mh, 1);
        do { $status = curl_multi_exec($mh, $active); } while ($status === CURLM_CALL_MULTI_PERFORM);
    }
    
    // Collect results
    foreach ($handles as $h) {
        $resp = curl_multi_getcontent($h['ch']);
        $code = curl_getinfo($h['ch'], CURLINFO_HTTP_CODE);
        $latency = round(curl_getinfo($h['ch'], CURLINFO_TOTAL_TIME) * 1000);
        curl_multi_remove_handle($mh, $h['ch']);
        curl_close($h['ch']);
        
        $text = null;
        if ($code >= 200 && $code < 300 && $resp) {
            $d = json_decode($resp, true);
            if ($h['format'] === 'gemini') $text = $d['candidates'][0]['content']['parts'][0]['text'] ?? null;
            elseif ($h['format'] === 'cohere') $text = $d['text'] ?? null;
            else $text = $d['choices'][0]['message']['content'] ?? null;
        }
        
        if ($text) {
            $results[] = [
                'provider' => $h['provider']['name'],
                'model' => $h['provider']['model'],
                'params' => $h['provider']['params'],
                'tier' => $h['provider']['tier'],
                'latency_ms' => $latency,
                'response' => $text,
            ];
        }
    }
    curl_multi_close($mh);
    return $results;
}

function synthesize_consensus($question, $results, $secrets) {
    if (count($results) < 2) return $results[0]['response'] ?? 'Pas assez de réponses pour un consensus.';
    
    $synthesis_prompt = "Tu es WEVIA Consensus Engine. Voici les réponses de " . count($results) . " IA différentes à la question: \"$question\"\n\n";
    foreach ($results as $i => $r) {
        $synthesis_prompt .= "--- " . strtoupper($r['provider']) . " ({$r['model']}, {$r['params']}B, {$r['latency_ms']}ms) ---\n{$r['response']}\n\n";
    }
    $synthesis_prompt .= "Synthétise un CONSENSUS en identifiant: 1) Points d'accord unanimes 2) Divergences 3) Ta recommandation finale. Sois concis.";
    
    // Use fastest provider for synthesis
    foreach ($ALL_PROVIDERS ?? [] as $p) { /* skip */ }
    
    // Use Cerebras for synthesis (fastest)
    $key = $secrets['CEREBRAS_API_KEY'] ?? '';
    if (!$key) $key = $secrets['GROQ_KEY'] ?? '';
    $synth_url = $key === ($secrets['CEREBRAS_API_KEY'] ?? '') ? 'https://api.cerebras.ai/v1/chat/completions' : 'https://api.groq.com/openai/v1/chat/completions';
    $synth_model = $key === ($secrets['CEREBRAS_API_KEY'] ?? '') ? 'qwen-3-235b-a22b-instruct-2507' : 'llama-3.3-70b-versatile';
    
    $body = json_encode(['model' => $synth_model, 'messages' => [['role' => 'user', 'content' => $synthesis_prompt]], 'max_tokens' => 500, 'temperature' => 0.2]);
    $ch = curl_init($synth_url);
    curl_setopt_array($ch, [CURLOPT_POST => true, CURLOPT_POSTFIELDS => $body,
        CURLOPT_HTTPHEADER => ['Content-Type: application/json', "Authorization: Bearer $key"],
        CURLOPT_RETURNTRANSFER => true, CURLOPT_TIMEOUT => 20, CURLOPT_SSL_VERIFYPEER => false]);
    $resp = curl_exec($ch); curl_close($ch);
    $d = json_decode($resp, true);
    return $d['choices'][0]['message']['content'] ?? 'Synthèse indisponible.';
}

// ═══ IA DISCOVERY — auto-detect new free providers ═══
function ia_discovery() {
    global $ALL_PROVIDERS, $secrets;
    $discovery = ['total_providers' => count($ALL_PROVIDERS), 'active' => 0, 'inactive' => 0, 'providers' => []];
    
    foreach ($ALL_PROVIDERS as $p) {
        $key = $p['key_name'] ? ($secrets[$p['key_name']] ?? '') : 'local';
        $active = (bool)$key || $p['name'] === 'ollama';
        $discovery['providers'][] = [
            'name' => $p['name'], 'tier' => $p['tier'], 'model' => $p['model'],
            'params' => $p['params'], 'active' => $active,
        ];
        if ($active) $discovery['active']++; else $discovery['inactive']++;
    }
    
    // Known free-tier endpoints to check
    $discovery['recommendations'] = [
        "Fireworks AI (free tier) — llama-3.3-70b, fast inference",
        "Lepton AI (free tier) — llama-3.3-70b, no rate limit",
        "HuggingFace Inference API — free, 1000+ models",
        "Cloudflare Workers AI — free tier, @cf/meta/llama-3-8b",
    ];
    
    return $discovery;
}

// ═══ ROUTING ═══
$input = json_decode(file_get_contents("php://input"), true);
$action = $_GET['action'] ?? $input['action'] ?? 'consensus';

switch ($action) {
    case 'consensus':
        $question = $input['question'] ?? $input['message'] ?? '';
        $max = intval($input['max_providers'] ?? 5);
        if (!$question) { echo json_encode(['error' => 'question required']); exit; }
        
        $t0 = microtime(true);
        $results = consensus_parallel($question, $ALL_PROVIDERS, $secrets, $max);
        $consensus = synthesize_consensus($question, $results, $secrets);
        $total_time = round((microtime(true) - $t0) * 1000);
        
        echo json_encode([
            'consensus' => $consensus,
            'providers_queried' => count($results),
            'total_time_ms' => $total_time,
            'individual_responses' => $results,
        ], JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE);
        break;
    
    case 'discovery':
        echo json_encode(ia_discovery(), JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE);
        break;
    
    case 'providers':
        $list = [];
        foreach ($ALL_PROVIDERS as $p) {
            $key = $p['key_name'] ? ($secrets[$p['key_name']] ?? '') : 'local';
            $list[] = ['name' => $p['name'], 'tier' => $p['tier'], 'model' => $p['model'], 'params' => $p['params'], 'active' => (bool)$key || $p['name'] === 'ollama'];
        }
        echo json_encode(['total' => count($list), 'providers' => $list], JSON_PRETTY_PRINT);
        break;
    
    case 'benchmark':
        $question = $input['question'] ?? 'Quelle est la meilleure approche pour le sovereign AI?';
        $results = [];
        foreach ($ALL_PROVIDERS as $p) {
            $key = $p['key_name'] ? ($secrets[$p['key_name']] ?? '') : 'local';
            if (!$key && $p['name'] !== 'ollama') continue;
            $t0 = microtime(true);
            $resp = call_provider($p, $question, $secrets, 10);
            $latency = round((microtime(true) - $t0) * 1000);
            $results[] = ['provider' => $p['name'], 'model' => $p['model'], 'params' => $p['params'],
                'latency_ms' => $latency, 'chars' => $resp ? strlen($resp) : 0, 'ok' => $resp !== null];
        }
        usort($results, fn($a, $b) => $a['latency_ms'] - $b['latency_ms']);
        echo json_encode(['benchmark' => $results, 'total' => count($results)], JSON_PRETTY_PRINT);
        break;
    
    case 'health':
        echo json_encode(['status' => 'ok', 'version' => '1.0', 'providers' => count($ALL_PROVIDERS),
            'active' => count(array_filter($ALL_PROVIDERS, fn($p) => ($p['key_name'] ? ($secrets[$p['key_name']] ?? '') : 'local')))]);
        break;
    
    default:
        echo json_encode(['error' => 'Unknown action. Use: consensus, discovery, providers, benchmark, health']);
}