<?php
ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);
error_reporting(E_ALL);
/**
 * pdf-files/headlessChrome_pdf.php
 *
 * Generic headless Chrome PDF generator.
 * Renders any registered report type to a native Chrome PDF.
 *
 * GET params:
 *   type   string  Report type key (see $reportTypes below)
 *   rid    int     Primary record ID
 *   rand   string  Security token (soil_records.rand / plant_records.rand etc.)
 *   cid    int     Client ID (optional, passed through to print page)
 *   stid   string  Soil/crop type (optional, passed through)
 *
 * Usage examples:
 *   /pdf-files/headlessChrome_pdf.php?type=soil&rid=123&rand=abc
 *   /pdf-files/headlessChrome_pdf.php?type=soil-combined&rid=123&rand=abc
 *   /pdf-files/headlessChrome_pdf.php?type=plant&rid=456&rand=def&cid=12
 *
 * To add a new report type: add an entry to $reportTypes below.
 */

require_once __DIR__ . '/../config/database.php';
require_once __DIR__ . '/../lib/auth.php';
require_once __DIR__ . '/../vendor/autoload.php';

use daandesmedt\PHPHeadlessChrome\HeadlessChrome;

if (session_status() === PHP_SESSION_NONE) {
    session_start();
}

requireLogin();

// ── Input ─────────────────────────────────────────────────────────────────────
$type     = trim($_GET['type']  ?? 'soil');
$recordId = (int)  ($_GET['rid']   ?? 0);
$randId   = trim(  $_GET['rand']   ?? '');
$clientId = (int)  ($_GET['cid']   ?? 0);
$stid     = trim(  $_GET['stid']   ?? '');

// ── Report type registry ──────────────────────────────────────────────────────
//
// 'print_page'    — path relative to site root; {rid}, {rand}, {cid}, {stid}
//                   placeholders are substituted at runtime
// 'verify_table'  — DB table used to verify the rand token before generating
// 'filename'      — prefix for the downloaded PDF filename
// 'label'         — human-readable name (for error messages)
//
$reportTypes = [
    // Individual pages
    'soil-analysis' => [
        'print_page'   => '/dashboard/crop-analysis/soil-test-data/soil-analysis.php?rid={rid}&rand={rand}&cid={cid}&stid={stid}&print=1',
        'verify_table' => 'soil_records',
        'filename'     => 'soil-analysis',
        'label'        => 'Soil Analysis',
    ],
    'soil-report' => [
        'print_page'   => '/dashboard/crop-analysis/soil-test-data/soil-report-pdf.php?rid={rid}&rand={rand}',
        'verify_table' => 'soil_records',
        'filename'     => 'soil-report',
        'label'        => 'Soil Report',
    ],
    // Combined: analysis + AI report in one PDF
    'soil' => [
        'print_page'   => '/dashboard/crop-analysis/soil-test-data/soil-print-combined.php?rid={rid}&rand={rand}&cid={cid}&stid={stid}',
        'verify_table' => 'soil_records',
        'filename'     => 'soil-analysis-report',
        'label'        => 'Soil Analysis & Report',
    ],
    // Plant
    'plant-analysis' => [
        'print_page'   => '/dashboard/crop-analysis/plant-test-data/plant-analysis.php?rid={rid}&rand={rand}&cid={cid}',
        'verify_table' => 'plant_records',
        'filename'     => 'plant-analysis',
        'label'        => 'Plant Analysis',
    ],
    'plant-report' => [
        'print_page'   => '/dashboard/crop-analysis/plant-test-data/plant-report-pdf.php?rid={rid}&rand={rand}',
        'verify_table' => 'plant_records',
        'filename'     => 'plant-report',
        'label'        => 'Plant Report',
    ],
    'plant' => [
        'print_page'   => '/dashboard/crop-analysis/plant-test-data/plant-print-combined.php?rid={rid}&rand={rand}&cid={cid}',
        'verify_table' => 'plant_records',
        'filename'     => 'plant-analysis-report',
        'label'        => 'Plant Analysis & Report',
    ],
    // Water
    'water-analysis' => [
        'print_page'   => '/dashboard/crop-analysis/water-test-data/water-analysis-pdf.php?rid={rid}&rand={rand}&cid={cid}',
        'verify_table' => 'water_records',
        'filename'     => 'water-analysis',
        'label'        => 'Water Analysis',
    ],
    'water-report' => [
        'print_page'   => '/dashboard/crop-analysis/water-test-data/water-report-pdf.php?rid={rid}&rand={rand}',
        'verify_table' => 'water_records',
        'filename'     => 'water-report',
        'label'        => 'Water Report',
    ],
    'water' => [
        'print_page'   => '/dashboard/crop-analysis/water-test-data/water-print-combined.php?rid={rid}&rand={rand}&cid={cid}',
        'verify_table' => 'water_records',
        'filename'     => 'water-analysis-report',
        'label'        => 'Water Analysis & Report',
    ],
    // Animal
    'animal-analysis' => [
        'print_page'   => '/dashboard/crop-analysis/animal-dietary-balance/animal-dietary-balance.php?rid={rid}&rand={rand}&cid={cid}',
        'verify_table' => 'animal_records',
        'filename'     => 'animal-analysis',
        'label'        => 'Animal Dietary Analysis',
    ],
    'animal-report' => [
        'print_page'   => '/dashboard/crop-analysis/animal-dietary-balance/animal-report-pdf.php?rid={rid}&rand={rand}',
        'verify_table' => 'animal_records',
        'filename'     => 'animal-report',
        'label'        => 'Animal Dietary Report',
    ],
    'animal' => [
        'print_page'   => '/dashboard/crop-analysis/animal-dietary-balance/animal-print-combined.php?rid={rid}&rand={rand}&cid={cid}',
        'verify_table' => 'animal_records',
        'filename'     => 'animal-dietary-report',
        'label'        => 'Animal Dietary Analysis & Report',
    ],
];

if (!isset($reportTypes[$type])) {
    http_response_code(400);
    $valid = implode(', ', array_keys($reportTypes));
    die("Unknown report type \"" . htmlspecialchars($type, ENT_QUOTES, 'UTF-8') . "\". Valid types: $valid");
}

$config = $reportTypes[$type];

if ($recordId <= 0 || $randId === '') {
    http_response_code(400);
    die('Missing required parameters: rid, rand');
}

// ── Verify record exists via its table ───────────────────────────────────────
$pdo   = getDBConnection();
$table = $config['verify_table'];

// Allowlist the table name against known tables to prevent SQL injection
$allowedTables = ['soil_records', 'plant_records', 'water_records', 'animal_records'];
if (!in_array($table, $allowedTables, true)) {
    http_response_code(500);
    die('Invalid verify_table in report type config.');
}

$stmt = $pdo->prepare("SELECT lab_no FROM `{$table}` WHERE id = ? AND rand = ? LIMIT 1");
$stmt->execute([$recordId, $randId]);
$record = $stmt->fetch();

if (!$record) {
    http_response_code(404);
    die('Record not found or access denied.');
}

// ── Write one-time print token ────────────────────────────────────────────────
$token    = bin2hex(random_bytes(16));
$expires  = time() + 120;

$tokenDir = __DIR__ . '/tokens';
if (!is_dir($tokenDir)) {
    mkdir($tokenDir, 0750, true);
}

file_put_contents($tokenDir . '/' . $token . '.tmp', json_encode([
    'rid'     => $recordId,
    'rand'    => $randId,
    'expires' => $expires,
    'type'    => $type,
]));

// ── Build print page URL ──────────────────────────────────────────────────────
$scheme  = (!empty($_SERVER['HTTPS']) && $_SERVER['HTTPS'] !== 'off') ? 'https' : 'http';
$host    = $_SERVER['HTTP_HOST'] ?? 'localhost';
$baseUrl = $scheme . '://' . $host;

$printPath = str_replace(
    ['{rid}', '{rand}',              '{cid}',   '{stid}'],
    [$recordId, urlencode($randId), $clientId, urlencode($stid)],
    $config['print_page']
);

$printUrl = $baseUrl . $printPath . '&ptoken=' . urlencode($token);

// ── Output directory + filename ───────────────────────────────────────────────
$outputDir = __DIR__;
$today     = date('Y-m-d');
$labNo     = preg_replace('/[^A-Za-z0-9\-_]/', '_', $record['lab_no'] ?? $recordId);
$filename  = $config['filename'] . '-' . $labNo . '-' . $today;

// ── Headless Chrome ───────────────────────────────────────────────────────────
$chromeBinary = '/usr/bin/google-chrome';
foreach (['/usr/bin/google-chrome', '/usr/bin/chromium-browser', '/usr/bin/chromium'] as $bin) {
    if (file_exists($bin)) { $chromeBinary = $bin; break; }
}

$arguments = [
    '--headless' => '',
    '--disable-gpu' => '',
    '--hide-scrollbars' => '',
    '--enable-viewport' => '',
    '--timeout=' => '6000',
    '--disable-web-security' => '',
    '--run-all-compositor-stages-before-draw' => '',
    '--virtual-time-budget' => '40000',
];

try {
    $chrome = new HeadlessChrome();
    $chrome->disablePDFHeader();
    $chrome->setUrl($printUrl);
    $chrome->setBinaryPath($chromeBinary);
    $chrome->setOutputDirectory($outputDir);
    $chrome->toPDF($filename . '.pdf');

    $pdfPath = $chrome->getFilePath();
} catch (Exception $e) {
    error_log('HeadlessChrome PDF error [' . $type . ']: ' . $e->getMessage());
    @unlink($tokenDir . '/' . $token . '.tmp');
    http_response_code(500);
    die('PDF generation failed: ' . htmlspecialchars($e->getMessage(), ENT_QUOTES, 'UTF-8'));
}

@unlink($tokenDir . '/' . $token . '.tmp');

// ── Stream PDF ────────────────────────────────────────────────────────────────
if (!file_exists($pdfPath)) {
    http_response_code(500);
    die('PDF file was not created. Ensure Chrome is installed at: ' . $chromeBinary);
}

chmod($pdfPath, 0644);

header('Content-Type: application/pdf');
header('Content-Disposition: attachment; filename="' . $filename . '.pdf"');
header('Content-Length: ' . filesize($pdfPath));
header('Expires: 0');
header('Cache-Control: must-revalidate');
header('Pragma: public');

readfile($pdfPath);

@unlink($pdfPath);
exit;