<?php
/**
 * WEVIA MEMORY API — Persistent cross-session memory via Qdrant
 * 
 * POST ?action=remember  {"key":"user_preference","value":"prefers French","context":"chat"}
 * GET  ?action=recall&q=preference
 * GET  ?action=list&limit=20
 * POST ?action=forget     {"key":"old_memory_key"}
 * GET  ?action=stats
 */
header("Content-Type: application/json; charset=utf-8");
header("Access-Control-Allow-Origin: *");
if ($_SERVER["REQUEST_METHOD"] === "OPTIONS") { http_response_code(200); exit; }

$QDRANT = "http://127.0.0.1:6333";
$COLLECTION = "wevia_memory";
$OLLAMA = "http://127.0.0.1:11434";

$input = json_decode(file_get_contents("php://input"), true) ?: [];
$action = $_GET["action"] ?? $input["action"] ?? "stats";

// Ensure collection exists
function ensureCollection() {
    global $QDRANT, $COLLECTION;
    $ch = curl_init("$QDRANT/collections/$COLLECTION");
    curl_setopt_array($ch, [CURLOPT_RETURNTRANSFER => true, CURLOPT_TIMEOUT => 3]);
    $r = curl_exec($ch); $code = curl_getinfo($ch, CURLINFO_HTTP_CODE); curl_close($ch);
    if ($code !== 200) {
        $ch2 = curl_init("$QDRANT/collections/$COLLECTION");
        curl_setopt_array($ch2, [
            CURLOPT_CUSTOMREQUEST => "PUT",
            CURLOPT_POSTFIELDS => json_encode(["vectors" => ["size" => 384, "distance" => "Cosine"]]),
            CURLOPT_HTTPHEADER => ["Content-Type: application/json"],
            CURLOPT_RETURNTRANSFER => true, CURLOPT_TIMEOUT => 5,
        ]);
        curl_exec($ch2); curl_close($ch2);
    }
}

// Embed text via Ollama all-minilm
function embed($text) {
    global $OLLAMA;
    $ch = curl_init("$OLLAMA/api/embeddings");
    curl_setopt_array($ch, [
        CURLOPT_POST => true,
        CURLOPT_POSTFIELDS => json_encode(["model" => "all-minilm", "prompt" => $text]),
        CURLOPT_HTTPHEADER => ["Content-Type: application/json"],
        CURLOPT_RETURNTRANSFER => true, CURLOPT_TIMEOUT => 10,
    ]);
    $r = curl_exec($ch); curl_close($ch);
    $d = json_decode($r, true);
    return $d["embedding"] ?? null;
}

ensureCollection();

switch ($action) {
    case "remember":
        $key = $input["key"] ?? "mem_" . time();
        $value = $input["value"] ?? "";
        $context = $input["context"] ?? "general";
        $timestamp = date("c");
        
        if (empty($value)) { echo json_encode(["error" => "value required"]); exit; }
        
        $vector = embed($value);
        if (!$vector) { echo json_encode(["error" => "embedding failed"]); exit; }
        
        $point = [
            "id" => abs(crc32($key)),
            "vector" => $vector,
            "payload" => [
                "key" => $key,
                "value" => $value,
                "context" => $context,
                "timestamp" => $timestamp,
                "type" => "memory",
            ],
        ];
        
        $ch = curl_init("$QDRANT/collections/wevia_memory/points");
        curl_setopt_array($ch, [
            CURLOPT_CUSTOMREQUEST => "PUT",
            CURLOPT_POSTFIELDS => json_encode(["points" => [$point]]),
            CURLOPT_HTTPHEADER => ["Content-Type: application/json"],
            CURLOPT_RETURNTRANSFER => true, CURLOPT_TIMEOUT => 5,
        ]);
        $r = curl_exec($ch); curl_close($ch);
        
        echo json_encode(["status" => "remembered", "key" => $key, "id" => abs(crc32($key))]);
        break;
        
    case "recall":
        $q = $_GET["q"] ?? $input["query"] ?? "";
        $limit = (int)($_GET["limit"] ?? 5);
        
        if (empty($q)) { echo json_encode(["error" => "query required"]); exit; }
        
        $vector = embed($q);
        if (!$vector) { echo json_encode(["error" => "embedding failed"]); exit; }
        
        $ch = curl_init("$QDRANT/collections/wevia_memory/points/search");
        curl_setopt_array($ch, [
            CURLOPT_POST => true,
            CURLOPT_POSTFIELDS => json_encode(["vector" => $vector, "limit" => $limit, "with_payload" => true]),
            CURLOPT_HTTPHEADER => ["Content-Type: application/json"],
            CURLOPT_RETURNTRANSFER => true, CURLOPT_TIMEOUT => 5,
        ]);
        $r = curl_exec($ch); curl_close($ch);
        $d = json_decode($r, true);
        
        $memories = [];
        foreach ($d["result"] ?? [] as $pt) {
            $memories[] = [
                "key" => $pt["payload"]["key"] ?? "",
                "value" => $pt["payload"]["value"] ?? "",
                "context" => $pt["payload"]["context"] ?? "",
                "score" => round($pt["score"], 3),
                "timestamp" => $pt["payload"]["timestamp"] ?? "",
            ];
        }
        echo json_encode(["query" => $q, "memories" => $memories, "count" => count($memories)]);
        break;
        
    case "list":
        $limit = (int)($_GET["limit"] ?? 20);
        $ch = curl_init("$QDRANT/collections/wevia_memory/points/scroll");
        curl_setopt_array($ch, [
            CURLOPT_POST => true,
            CURLOPT_POSTFIELDS => json_encode(["limit" => $limit, "with_payload" => true]),
            CURLOPT_HTTPHEADER => ["Content-Type: application/json"],
            CURLOPT_RETURNTRANSFER => true, CURLOPT_TIMEOUT => 5,
        ]);
        $r = curl_exec($ch); curl_close($ch);
        $d = json_decode($r, true);
        
        $memories = [];
        foreach ($d["result"]["points"] ?? [] as $pt) {
            $memories[] = $pt["payload"];
        }
        echo json_encode(["memories" => $memories, "count" => count($memories)]);
        break;
        
    case "forget":
        $key = $input["key"] ?? "";
        if (empty($key)) { echo json_encode(["error" => "key required"]); exit; }
        
        $id = abs(crc32($key));
        $ch = curl_init("$QDRANT/collections/wevia_memory/points/delete");
        curl_setopt_array($ch, [
            CURLOPT_POST => true,
            CURLOPT_POSTFIELDS => json_encode(["points" => [$id]]),
            CURLOPT_HTTPHEADER => ["Content-Type: application/json"],
            CURLOPT_RETURNTRANSFER => true, CURLOPT_TIMEOUT => 5,
        ]);
        curl_exec($ch); curl_close($ch);
        echo json_encode(["status" => "forgotten", "key" => $key]);
        break;
        
    case "stats":
        $ch = curl_init("$QDRANT/collections/wevia_memory");
        curl_setopt_array($ch, [CURLOPT_RETURNTRANSFER => true, CURLOPT_TIMEOUT => 3]);
        $r = curl_exec($ch); curl_close($ch);
        $d = json_decode($r, true);
        echo json_encode([
            "collection" => "wevia_memory",
            "points" => $d["result"]["points_count"] ?? 0,
            "vectors" => $d["result"]["vectors_count"] ?? 0,
            "status" => $d["result"]["status"] ?? "unknown",
        ]);
        break;
}