<?php
// purpose: serve a real square PNG for Sites A2H / iPhone apple-touch-icon
// author: MD Hub
// date: 2026-09-07
// iOS rejects JPEG-as-PNG, SVG, and mismatched Content-Type on Add to Home Screen.

header('Cache-Control: public, max-age=86400');

$size = (int)($_GET['size'] ?? 180);
if ($size < 32) $size = 32;
if ($size > 512) $size = 512;
$site_id = (int)($_GET['site_id'] ?? 0);

$repo = dirname(__DIR__);
$name = 'Site';
$theme = '#4C1D95';
$logo = '';

if (!function_exists('imagecreatetruecolor')) {
	header('HTTP/1.1 501 Not Implemented');
	header('Content-Type: text/plain; charset=utf-8');
	echo 'GD not available';
	exit;
}

try {
	require_once $repo . '/functions/sqlfunctions.php';
	if (is_file($repo . '/functions/system.php')) {
		require_once $repo . '/functions/system.php';
	}
	$host = strtolower(preg_replace('/:\d+$/', '', (string)($_SERVER['HTTP_HOST'] ?? '')));
	if ($site_id > 0) {
		$row = mysql_prepare_get(
			"SELECT site_id, site_name, site_color, colors, logo_url, wizard_data FROM site_data WHERE site_id=? LIMIT 1",
			'md_hub',
			[$site_id]
		);
	} else {
		$row = mysql_prepare_get(
			"SELECT S.site_id, S.site_name, S.site_color, S.colors, S.logo_url, S.wizard_data
			 FROM domains D INNER JOIN site_data S ON S.site_id=D.site_id
			 WHERE D.host=? ORDER BY D.domain_id ASC LIMIT 1",
			'md_hub',
			[$host]
		);
	}
	if (isset($row[0][0])) {
		$site_id = (int)$row[0][0];
		$name = trim((string)($row[0][1] ?? '')) ?: $name;
		$theme_raw = trim((string)($row[0][2] ?? $theme));
		$colors_json = (string)($row[0][3] ?? '');
		$logo = trim((string)($row[0][4] ?? ''));
		$wiz = @json_decode((string)($row[0][5] ?? ''), true);
		if ($logo === '' && is_array($wiz) && !empty($wiz['logo_url'])) {
			$logo = trim((string)$wiz['logo_url']);
		}
		if ($colors_json !== '') {
			$dec = @json_decode($colors_json, true);
			if (is_array($dec) && !empty($dec[0])) {
				$theme_raw = (string)$dec[0];
			}
		}
		if (function_exists('sites_color_to_hex') && function_exists('sites_normalize_color')) {
			$theme = sites_color_to_hex(sites_normalize_color($theme_raw));
		} elseif (strpos($theme_raw, '#') === 0) {
			$theme = $theme_raw;
		}
	}
} catch (Throwable $e) {
	// generated fallback below
}

function a2h_icon_hex_rgb(string $hex): array {
	$hex = ltrim(trim($hex), '#');
	if (strlen($hex) === 3) {
		$hex = $hex[0].$hex[0].$hex[1].$hex[1].$hex[2].$hex[2];
	}
	if (!preg_match('/^[0-9a-fA-F]{6}$/', $hex)) {
		return [76, 29, 149];
	}
	return [hexdec(substr($hex, 0, 2)), hexdec(substr($hex, 2, 2)), hexdec(substr($hex, 4, 2))];
}

function a2h_icon_local_logo(string $logo, string $repo): string {
	$logo = trim($logo);
	if ($logo === '') return '';
	$path = '';
	if (preg_match('#^https?://[^/]+(/file_repository/.+)$#i', $logo, $m)) {
		$path = $m[1];
	} elseif (strpos($logo, '/file_repository/') === 0) {
		$path = $logo;
	} elseif (preg_match('#^file_repository/#', $logo)) {
		$path = '/' . $logo;
	}
	if ($path === '' || strpos($path, '..') !== false) {
		return '';
	}
	$full = $repo . $path;
	return is_file($full) ? $full : '';
}

function a2h_icon_load(string $file) {
	$raw = @file_get_contents($file);
	if ($raw === false || $raw === '') return null;
	$im = @imagecreatefromstring($raw);
	return $im ?: null;
}

function a2h_icon_letter_png(int $size, string $name, string $theme): void {
	[$r, $g, $b] = a2h_icon_hex_rgb($theme);
	$im = imagecreatetruecolor($size, $size);
	imagealphablending($im, true);
	$bg = imagecolorallocate($im, $r, $g, $b);
	imagefilledrectangle($im, 0, 0, $size - 1, $size - 1, $bg);
	$letter = strtoupper(substr(preg_replace('/[^A-Za-z0-9]/', '', $name) ?: 'S', 0, 1));
	$white = imagecolorallocate($im, 255, 255, 255);
	$font = 5;
	$fw = imagefontwidth($font) * strlen($letter);
	$fh = imagefontheight($font);
	$scale = max(8, (int)round($size / 28));
	$tmp = imagecreatetruecolor($fw, $fh);
	$tbg = imagecolorallocate($tmp, $r, $g, $b);
	imagefilledrectangle($tmp, 0, 0, $fw, $fh, $tbg);
	imagestring($tmp, $font, 0, 0, $letter, $white);
	$dw = $fw * $scale;
	$dh = $fh * $scale;
	imagecopyresampled(
		$im,
		$tmp,
		(int)(($size - $dw) / 2),
		(int)(($size - $dh) / 2),
		0,
		0,
		$dw,
		$dh,
		$fw,
		$fh
	);
	imagedestroy($tmp);
	header('Content-Type: image/png');
	imagepng($im);
	imagedestroy($im);
}

function a2h_icon_from_file(string $file, int $size, string $theme): bool {
	$src = a2h_icon_load($file);
	if (!$src) return false;
	[$r, $g, $b] = a2h_icon_hex_rgb($theme);
	$out = imagecreatetruecolor($size, $size);
	imagealphablending($out, false);
	imagesavealpha($out, false);
	$bg = imagecolorallocate($out, $r, $g, $b);
	imagefilledrectangle($out, 0, 0, $size - 1, $size - 1, $bg);
	imagealphablending($out, true);
	$sw = imagesx($src);
	$sh = imagesy($src);
	if ($sw < 1 || $sh < 1) {
		imagedestroy($src);
		imagedestroy($out);
		return false;
	}
	$pad = (int)round($size * 0.08);
	$box = $size - ($pad * 2);
	$scale = min($box / $sw, $box / $sh);
	$dw = max(1, (int)round($sw * $scale));
	$dh = max(1, (int)round($sh * $scale));
	$dx = (int)(($size - $dw) / 2);
	$dy = (int)(($size - $dh) / 2);
	imagecopyresampled($out, $src, $dx, $dy, 0, 0, $dw, $dh, $sw, $sh);
	imagedestroy($src);
	header('Content-Type: image/png');
	imagepng($out);
	imagedestroy($out);
	return true;
}

$local = a2h_icon_local_logo($logo, $repo);
if ($local !== '' && a2h_icon_from_file($local, $size, $theme)) {
	exit;
}
a2h_icon_letter_png($size, $name, $theme);
exit;