<?php
/**
 * Google Fonts, served from the site: when a bar uses one, its files are downloaded once into
 * wp-content/uploads/runline-fonts/<font>/ and loaded from there. Visitors' browsers never contact Google (GDPR).
 */

defined( 'ABSPATH' ) || exit;

/**
 * Fonts to choose from: family => fallback.
 */
function runline_google_fonts() {
	return apply_filters(
		'runline_google_fonts',
		array(
			'Inter'            => 'sans-serif',
			'Roboto'           => 'sans-serif',
			'Open Sans'        => 'sans-serif',
			'Montserrat'       => 'sans-serif',
			'Poppins'          => 'sans-serif',
			'Lato'             => 'sans-serif',
			'Nunito'           => 'sans-serif',
			'Raleway'          => 'sans-serif',
			'Rubik'            => 'sans-serif',
			'Work Sans'        => 'sans-serif',
			'DM Sans'          => 'sans-serif',
			'Manrope'          => 'sans-serif',
			'Space Grotesk'    => 'sans-serif',
			'Oswald'           => 'sans-serif',
			'Bebas Neue'       => 'sans-serif',
			'Anton'            => 'sans-serif',
			'Playfair Display' => 'serif',
			'Merriweather'     => 'serif',
			'Lobster'          => 'cursive',
			'Pacifico'         => 'cursive',
		)
	);
}

/**
 * Family of a "g:<family>" font choice, or "" for the other fonts.
 */
function runline_google_family( $font ) {
	if ( 0 !== strpos( (string) $font, 'g:' ) ) {
		return '';
	}
	$family = substr( $font, 2 );
	return isset( runline_google_fonts()[ $family ] ) ? $family : '';
}

function runline_font_slug( $family ) {
	return sanitize_title( $family );
}

/**
 * Folder and URL of the local copies.
 */
function runline_fonts_dir() {
	$uploads = wp_upload_dir( null, false );
	return array(
		'dir' => trailingslashit( $uploads['basedir'] ) . 'runline-fonts',
		'url' => trailingslashit( $uploads['baseurl'] ) . 'runline-fonts',
	);
}

/**
 * URL of the local CSS of a font ("" while it is not downloaded).
 */
function runline_font_css_url( $family ) {
	$base = runline_fonts_dir();
	$slug = runline_font_slug( $family );
	return file_exists( $base['dir'] . '/' . $slug . '/font.css' ) ? $base['url'] . '/' . $slug . '/font.css' : '';
}

/**
 * Downloads a font (CSS + woff2 files) once. Runs in the admin when a bar with this font is saved or previewed.
 *
 * @param string $family Font family.
 * @return string URL of the local CSS, or "" on failure.
 */
function runline_font_download( $family ) {
	if ( ! isset( runline_google_fonts()[ $family ] ) ) {
		return '';
	}
	$ready = runline_font_css_url( $family );
	if ( $ready ) {
		return $ready;
	}
	$base   = runline_fonts_dir();
	$slug   = runline_font_slug( $family );
	$folder = $base['dir'] . '/' . $slug;
	$url    = 'https://fonts.googleapis.com/css2?family=' . rawurlencode( $family ) . ':wght@400;500;600;700;800&display=swap';
	// A current browser gets woff2 files.
	$answer = wp_remote_get(
		$url,
		array(
			'timeout'    => 20,
			'user-agent' => 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0 Safari/537.36',
		)
	);
	if ( is_wp_error( $answer ) || 200 !== wp_remote_retrieve_response_code( $answer ) ) {
		// Fonts without some of the weights: ask for the regular one.
		$answer = wp_remote_get(
			str_replace( ':wght@400;500;600;700;800', '', $url ),
			array(
				'timeout'    => 20,
				'user-agent' => 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/130.0 Safari/537.36',
			)
		);
		if ( is_wp_error( $answer ) || 200 !== wp_remote_retrieve_response_code( $answer ) ) {
			return '';
		}
	}
	$css = wp_remote_retrieve_body( $answer );
	if ( ! preg_match_all( '#url\((https://fonts\.gstatic\.com/[^)]+\.woff2)\)#', $css, $files ) ) {
		return '';
	}
	if ( ! wp_mkdir_p( $folder ) ) {
		return '';
	}
	foreach ( array_unique( $files[1] ) as $i => $remote ) {
		$name = $slug . '-' . $i . '.woff2';
		$file = wp_remote_get( $remote, array( 'timeout' => 20 ) );
		if ( is_wp_error( $file ) || 200 !== wp_remote_retrieve_response_code( $file ) ) {
			return '';
		}
		file_put_contents( $folder . '/' . $name, wp_remote_retrieve_body( $file ) ); // phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_file_put_contents -- a font file into uploads.
		$css = str_replace( $remote, $name, $css );
	}
	file_put_contents( $folder . '/font.css', $css ); // phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_file_put_contents -- the font CSS into uploads.
	return runline_font_css_url( $family );
}

/**
 * Loads the local font of a bar on the page.
 *
 * @param array $settings Bar settings.
 */
function runline_enqueue_font( $settings ) {
	$family = runline_google_family( $settings['font'] );
	$url    = $family ? runline_font_css_url( $family ) : '';
	if ( $url ) {
		wp_enqueue_style( 'runline-font-' . runline_font_slug( $family ), $url, array(), RUNLINE_VERSION );
	}
}

// Saving a bar downloads its font.
add_action(
	'runline_settings_saved',
	function ( $bar_id, $settings ) {
		$family = runline_google_family( $settings['font'] );
		if ( $family ) {
			runline_font_download( $family );
		}
	},
	10,
	2
);