<?php
header('Content-Type: application/json');
require_once __DIR__ . '/../db/config.php';
require_once __DIR__ . '/../ai/LocalAIApi.php';

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

if (!$data) {
    echo json_encode(['success' => false, 'error' => 'Invalid request data']);
    exit;
}

$action = $data['action'] ?? 'magic';
$original_prompt = $data['original_prompt'] ?? '';
$edit_prompt = $data['edit_prompt'] ?? '';
$image_url = $data['image_url'] ?? '';

if (empty($original_prompt) && empty($edit_prompt)) {
    echo json_encode(['success' => false, 'error' => 'Prompt is required']);
    exit;
}

try {
    $new_prompt = '';
    
    // Step 1: Use AI to merge prompts or handle actions
    if ($action === 'magic') {
        $ai_payload = [
            'input' => [
                ['role' => 'system', 'content' => 'You are an AI Image Prompt Engineer. Your task is to combine an original image description with a new edit instruction into a single, highly detailed, and cohesive new image prompt. Maintain the core subject and style of the original but incorporate the changes naturally. Output ONLY the new prompt, no explanation.'],
                ['role' => 'user', 'content' => "Original description: {$original_prompt}\nEdit instruction: {$edit_prompt}\nNew Prompt:"]
            ]
        ];

        $ai_response = LocalAIApi::createResponse($ai_payload);
        if (!empty($ai_response['success'])) {
            $new_prompt = LocalAIApi::extractText($ai_response);
        } else {
            // Fallback: simple concatenation
            $new_prompt = $original_prompt . ", " . $edit_prompt;
        }
    } else if ($action === 'remove_bg') {
        $new_prompt = "{$original_prompt}, isolated on a pure white background, studio lighting, professional product photography";
    } else if ($action === 'upscale') {
        $new_prompt = "{$original_prompt}, extremely detailed, 8k resolution, masterpiece, sharp focus, hyperrealistic";
    }

    if (empty($new_prompt)) {
        $new_prompt = $original_prompt . " " . $edit_prompt;
    }

    // Step 2: Generate new image using Pollinations (Flux)
    $seed = rand(1000, 99999);
    $encoded_prompt = urlencode($new_prompt);
    $api_url = "https://image.pollinations.ai/prompt/{$encoded_prompt}?width=1024&height=1024&seed={$seed}&model=flux&nologo=true";
    
    $filename = 'assets/images/pexels/gen_edit_' . md5($new_prompt . $seed) . '.jpg';
    $target = __DIR__ . '/../' . $filename;
    
    // Download the image
    $ch = curl_init($api_url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
    curl_setopt($ch, CURLOPT_TIMEOUT, 60);
    $image_data = curl_exec($ch);
    $http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    curl_close($ch);

    if ($http_code === 200 && $image_data) {
        if (!is_dir(__DIR__ . '/../assets/images/pexels/')) {
            mkdir(__DIR__ . '/../assets/images/pexels/', 0775, true);
        }
        file_put_contents($target, $image_data);
        
        // Save to history
        $stmt = db()->prepare("INSERT INTO media_history (type, prompt, result_url) VALUES (?, ?, ?)");
        $stmt->execute(['photo', "[Edit] " . $new_prompt, $filename]);

        echo json_encode([
            'success' => true,
            'url' => $filename,
            'new_prompt' => $new_prompt
        ]);
    } else {
        echo json_encode(['success' => false, 'error' => 'Failed to generate image from AI: HTTP ' . $http_code]);
    }

} catch (Exception $e) {
    echo json_encode(['success' => false, 'error' => $e->getMessage()]);
}