<?php
header('Content-Type: application/json');
header('Access-Control-Allow-Origin: *');
header('Access-Control-Allow-Methods: POST, OPTIONS');
header('Access-Control-Allow-Headers: Content-Type');

if ($_SERVER['REQUEST_METHOD'] === 'OPTIONS') {
    http_response_code(200);
    exit;
}

if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
    http_response_code(405);
    echo json_encode(['error' => 'Method not allowed. Use POST.']);
    exit;
}

$input = json_decode(file_get_contents('php://input'), true);

if (empty($input['agent']) || empty($input['email'])) {
    http_response_code(400);
    echo json_encode([
        'error' => 'Missing required fields',
        'required' => ['agent', 'email'],
        'example' => [
            'agent' => 'single-agent',
            'email' => 'your@email.com'
        ]
    ]);
    exit;
}

$agent = $input['agent'];
$email = filter_var($input['email'], FILTER_VALIDATE_EMAIL);
$name = $input['name'] ?? '';

$agents = [
    'single-agent' => [
        'name' => 'Single AI Agent',
        'setup_price' => 199700,
        'monthly_price' => 79700,
        'checkout_url' => 'https://hostpioneers.com/checkout-single.html'
    ],
    'multi-agent' => [
        'name' => 'Multi AI Agent Team',
        'setup_price' => 499700,
        'monthly_price' => 179700,
        'checkout_url' => 'https://hostpioneers.com/checkout-multi.html'
    ]
];

if (!isset($agents[$agent])) {
    http_response_code(400);
    echo json_encode([
        'error' => 'Invalid agent type',
        'valid_agents' => array_keys($agents)
    ]);
    exit;
}

$agentConfig = $agents[$agent];

$stripeSecretKey = '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';

$stripeUrl = 'https://api.stripe.com/v1/checkout/sessions';

$data = [
    'payment_method_types[]' => 'card',
    'line_items[0][price_data][product_data][name]' => $agentConfig['name'] . ' - Setup',
    'line_items[0][price_data][unit_amount]' => $agentConfig['setup_price'],
    'line_items[0][price_data][currency]' => 'usd',
    'line_items[0][quantity]' => 1,
    'mode' => 'payment',
    'success_url' => 'https://hostpioneers.com/success.html?agent=' . urlencode($agent),
    'cancel_url' => $agentConfig['checkout_url'],
    'customer_email' => $email,
    'metadata' => [
        'agent_type' => $agent,
        'customer_name' => $name
    ]
];

$ch = curl_init($stripeUrl);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($data));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    'Authorization: Bearer ' . $stripeSecretKey,
    'Content-Type: application/x-www-form-urlencoded'
]);

$response = curl_exec($ch);
$httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
curl_close($ch);

$responseData = json_decode($response, true);

if ($httpCode === 200 && isset($responseData['url'])) {
    echo json_encode([
        'success' => true,
        'checkout_url' => $responseData['url'],
        'session_id' => $responseData['id'],
        'agent' => $agentConfig['name'],
        'email' => $email,
        'notification' => 'Telegram + Email on payment'
    ]);
} else {
    http_response_code(500);
    echo json_encode([
        'error' => 'Failed to create checkout session',
        'details' => $responseData['error'] ?? 'Unknown error'
    ]);
}