Wallos/endpoints/ai/generate_recommendations.php

<?php
set_time_limit(300);
require_once '../../includes/connect_endpoint.php';
require_once '../../includes/validate_endpoint.php';

function getPricePerMonth($cycle, $frequency, $price)
{
    switch ($cycle) {
        case 1:
            return $price * (30 / $frequency);        // daily
        case 2:
            return $price * (4.35 / $frequency);       // weekly
        case 3:
            return $price / $frequency;                // monthly
        case 4:
            return $price / (12 * $frequency);         // yearly
        default:
            return $price;
    }
}

function describeFrequency($cycle, $frequency)
{
    $unit = match ($cycle) {
        1 => 'day',
        2 => 'week',
        3 => 'month',
        4 => 'year',
        default => 'unit'
    };

    if ($frequency == 1) {
        return "Every $unit";
    } else {
        return "Every $frequency {$unit}s";
    }
}

function describeCurrency($currencyId, $currencies)
{
    return $currencies[$currencyId]['code'] ?? '';
}

// Get AI settings for the user from the database
$stmt = $db->prepare("SELECT * FROM ai_settings WHERE user_id = ?");
$stmt->bindValue(1, $userId, SQLITE3_INTEGER);
$result = $stmt->execute();
$aiSettings = $result->fetchArray(SQLITE3_ASSOC);
$stmt->close();
if (!$aiSettings) {
    $response = [
        "success" => false,
        "message" => translate('error', $i18n)
    ];
    echo json_encode($response);
    exit;
}

$type = isset($aiSettings['type']) ? $aiSettings['type'] : '';
$enabled = isset($aiSettings['enabled']) ? (bool) $aiSettings['enabled'] : false;
$model = isset($aiSettings['model']) ? $aiSettings['model'] : '';
$host = "";
$apiKey = "";
if (!in_array($type, ['chatgpt', 'gemini', 'openrouter', 'ollama']) || !$enabled || empty($model)) {
    $response = [
        "success" => false,
        "message" => translate('error', $i18n)
    ];
    echo json_encode($response);
    exit;
}

if ($type == 'ollama') {
    $host = isset($aiSettings['url']) ? $aiSettings['url'] : '';
    if (empty($host)) {
        $response = [
            "success" => false,
            "message" => translate('invalid_host', $i18n)
        ];
        echo json_encode($response);
        exit;
    }
} else {
    $apiKey = isset($aiSettings['api_key']) ? $aiSettings['api_key'] : '';
    if (empty($apiKey)) {
        $response = [
            "success" => false,
            "message" => translate('invalid_api_key', $i18n)
        ];
        echo json_encode($response);
        exit;
    }
}

// We have everything we need, fetch information from the dabase to send to the AI API
// Get the categories from the database for user with ID 1
$stmt = $db->prepare("SELECT * FROM categories WHERE user_id = :user_id");
$stmt->bindValue(':user_id', $userId, SQLITE3_INTEGER);
$result = $stmt->execute();
$categories = [];
while ($row = $result->fetchArray(SQLITE3_ASSOC)) {
    $categories[$row['id']] = $row;
}

// Get the currencies from the database for user with ID 1
$stmt = $db->prepare("SELECT * FROM currencies WHERE user_id = :user_id");
$stmt->bindValue(':user_id', $userId, SQLITE3_INTEGER);
$result = $stmt->execute();
$currencies = [];
while ($row = $result->fetchArray(SQLITE3_ASSOC)) {
    $currencies[$row['id']] = $row;
}

// Get houswhold members from the database for user with ID 1
$stmt = $db->prepare("SELECT * FROM household WHERE user_id = :user_id");
$stmt->bindValue(':user_id', $userId, SQLITE3_INTEGER);
$result = $stmt->execute();
$members = [];
while ($row = $result->fetchArray(SQLITE3_ASSOC)) {
    $members[$row['id']] = $row;
}

// Get language from the user table
$stmt = $db->prepare("SELECT language FROM user WHERE id = :user_id");
$stmt->bindValue(':user_id', $userId, SQLITE3_INTEGER);
$result = $stmt->execute();
$userLanguage = $result->fetchArray(SQLITE3_ASSOC)['language'] ?? 'en';

// Get name from includes/i18n/languages.php
require_once '../../includes/i18n/languages.php';
$userLanguageName = $languages[$userLanguage]['name'] ?? 'English';

// Get subscriptions from the database for user with ID 1
$stmt = $db->prepare("SELECT * FROM subscriptions WHERE user_id = :user_id AND inactive = 0");
$stmt->bindValue(':user_id', $userId, SQLITE3_INTEGER);
$result = $stmt->execute();

$subscriptions = [];
while ($row = $result->fetchArray(SQLITE3_ASSOC)) {
    $subscriptions[] = $row;
}

if (!empty($subscriptions)) {
    $subscriptionsForAI = [];

    foreach ($subscriptions as $row) {
        if ($row['inactive'])
            continue;

        $price = round($row['price'], 2);
        $currencyCode = $currencies[$row['currency_id']]['code'] ?? '';
        $priceFormatted = $currencyCode ? "$price $currencyCode" : "$price";

        $payerName = $members[$row['payer_user_id']]['name'] ?? 'Unknown';

        $subscriptionsForAI[] = [
            'name' => $row['name'],
            'price' => $priceFormatted,
            'frequency' => describeFrequency($row['cycle'], $row['frequency']),
            'category' => $categories[$row['category_id']]['name'] ?? 'Uncategorized',
            'payer' => $payerName
        ];
    }

    // encode
    $aiDataJson = json_encode($subscriptionsForAI, JSON_PRETTY_PRINT);
} else {
    $response = [
        "success" => false,
        "message" => translate('error', $i18n)
    ];
    echo json_encode($response);
    exit;
}

$prompt = <<<PROMPT
    You are a helpful assistant designed to help users save money on digital subscriptions.

    The user has shared a list of their active subscriptions across household members. For each subscription, you are given:
    - Name of the service
    - Price (in original currency)
    - Payment frequency (e.g., every month, every year, etc.)
    - Category
    - Payer (which household member pays for it)

    Analyze the data and give 3 to 7 smart and specific recommendations to reduce subscription costs. If possible, include estimated savings for each suggestion.

    Follow these guidelines:
    - Do NOT suggest switching to family or group plans unless two or more different household members are paying for the same or similar service.
    - Recognize known feature overlaps, such as:
    • YouTube Premium includes YouTube Music.
    • Amazon Prime includes Prime Video.
    • Google One, iCloud+, and Proton all offer cloud storage.
    • Real Debrid, All Debrid, and Premiumize offer similar download capabilities.
    - Suggest rotating or cancelling subscriptions that serve similar purposes (e.g. multiple streaming or IPTV services).
    - Recommend switching from monthly to yearly plans only if it provides clear savings and the user is likely to keep the service long-term.
    - Suggest looking for promo or new customer deals if a service appears overpriced.
    - Only recommend cancelling rarely used services if they do not provide unique value.

    Return the result as a JSON array. Each item in the array should have:
    - "title": a short summary of the suggestion
    - "description": a longer explanation with reasoning
    - "savings": a rough estimate like "10 EUR/month" or "60 EUR/year" (if possible)

    If possible, all text should be in the user's language: {$userLanguageName}. Otherwise, use English.

    Do not include any other text, just the JSON output. Absolutely no additional comments or explanations.

    Here is the user’s data:
    PROMPT;

$prompt .= "\n\n" . json_encode($subscriptionsForAI, JSON_PRETTY_PRINT);

// Prepare the cURL request
$ch = curl_init();

if ($type === 'ollama') {
    curl_setopt($ch, CURLOPT_URL, $host . '/api/generate');
    curl_setopt($ch, CURLOPT_POST, true);
    curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode(['model' => $model, 'prompt' => $prompt, 'stream' => false]));
} else {
    $headers = ['Content-Type: application/json'];

    if ($type === 'chatgpt') {
        $headers[] = 'Authorization: Bearer ' . $apiKey;
        curl_setopt($ch, CURLOPT_URL, 'https://api.openai.com/v1/chat/completions');
        curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode([
            'model' => $model,
            'messages' => [['role' => 'user', 'content' => $prompt]]
        ]));
    } elseif ($type === 'gemini') {
        curl_setopt(
            $ch,
            CURLOPT_URL,
            'https://generativelanguage.googleapis.com/v1beta/models/' . urlencode($model) .
            ':generateContent?key=' . urlencode($apiKey)
        );
        curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode([
            'contents' => [
                [
                    'parts' => [['text' => $prompt]]
                ]
            ]
        ]));
    } elseif ($type === 'openrouter') {
        $headers[] = 'Authorization: Bearer ' . $apiKey;
        curl_setopt($ch, CURLOPT_URL, 'https://openrouter.ai/api/v1/chat/completions');
        curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode([
            'model' => $model,
            'messages' => [['role' => 'user', 'content' => $prompt]]
        ]));
    }

    curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
}

curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_TIMEOUT, 300);

// Execute the cURL request
$reply = curl_exec($ch);

// Check for errors
if (curl_errno($ch)) {
    $response = [
        "success" => false,
        "message" => curl_error($ch)
    ];
    echo json_encode($response);
    exit;
}

// Close the cURL session
curl_close($ch);

// Try to decode the AI's JSON reply
$replyData = json_decode($reply, true); // decode into array
if (($type === 'chatgpt' || $type === 'openrouter') && isset($replyData['choices'][0]['message']['content'])) {
    $recommendationsJson = $replyData['choices'][0]['message']['content'];
    $recommendations = json_decode($recommendationsJson, true);
} elseif ($type === 'gemini' && isset($replyData['candidates'][0]['content']['parts'][0]['text'])) {
    $recommendationsJson = $replyData['candidates'][0]['content']['parts'][0]['text'];
    // Gemini has a habit of returning the JSON wrapped in markdown syntax, no matter the prompting, strip before parsing.
    $recommendationsJson = preg_replace('/^```json\s*|\s*```$/m', '', $recommendationsJson);
    $recommendationsJson = trim($recommendationsJson);
    $recommendations = json_decode($recommendationsJson, true);
} else {
    $recommendations = json_decode($replyData['response'], true);
}

if (json_last_error() === JSON_ERROR_NONE && is_array($recommendations)) {
    // Remove old recommendations for this user
    $stmt = $db->prepare("DELETE FROM ai_recommendations WHERE user_id = :user_id");
    $stmt->bindValue(':user_id', $userId, SQLITE3_INTEGER);
    $stmt->execute();

    // Insert each new recommendation
    $insert = $db->prepare("
            INSERT INTO ai_recommendations (user_id, type, title, description, savings)
            VALUES (:user_id, :type, :title, :description, :savings)
        ");

    foreach ($recommendations as $rec) {
        $insert->bindValue(':user_id', $userId, SQLITE3_INTEGER);
        $insert->bindValue(':type', 'subscription', SQLITE3_TEXT); // or any category you want
        $insert->bindValue(':title', $rec['title'] ?? '', SQLITE3_TEXT);
        $insert->bindValue(':description', $rec['description'] ?? '', SQLITE3_TEXT);
        $insert->bindValue(':savings', $rec['savings'] ?? '', SQLITE3_TEXT);
        $insert->execute();
    }

    $response = [
        "success" => true,
        "message" => translate('success', $i18n),
        "recommendations" => $recommendations
    ];
    echo json_encode($response);
    exit;
} else {
    $response = [
        "success" => false,
        "message" => translate('error', $i18n),
        "json_error" => json_last_error_msg()
    ];
    echo json_encode($response);
    exit;
}