As the sun rises and the forest mist clears, and the clouds return and the caves darken, these changes of light and shadow are the morning and evening in the mountains. Wildflowers bloom with their subtle fragrance, fine trees flourish with their dense shade, the wind and frost are pure and clean, and the water recedes to reveal the rocks—these are the four seasons in the mountains. Going out in the morning and returning in the evening, the scenery of the four seasons is different, and the joy is endless.至于负者歌于途,行者休于树,前者呼,后者应,伛偻提携,往来而不绝者,滁人游也。临溪而渔,溪深而鱼肥,酿泉为酒,泉香而酒洌,山肴野蔌,杂然而前陈者,太守宴也。宴酣之乐,非丝非竹,射者中,弈者胜,觥筹交错,起坐而喧哗者,众宾欢也。苍颜白发,颓然乎其间者,太守醉也。
<?php
/**
* WP_Font_Face class.
*
* @package WordPress
* @subpackage Fonts
* @since 6.4.0
*/
/**
* Font Face generates and prints `@font-face` styles for given fonts.
*
* @since 6.4.0
*/
class WP_Font_Face {
/**
* The font-face property defaults.
*
* @since 6.4.0
*
* @var string[]
*/
private $font_face_property_defaults = array(
'font-family' => '',
'font-style' => 'normal',
'font-weight' => '400',
'font-display' => 'fallback',
);
/**
* Valid font-face property names.
*
* @since 6.4.0
*
* @var string[]
*/
private $valid_font_face_properties = array(
'ascent-override',
'descent-override',
'font-display',
'font-family',
'font-stretch',
'font-style',
'font-weight',
'font-variant',
'font-feature-settings',
'font-variation-settings',
'line-gap-override',
'size-adjust',
'src',
'unicode-range',
);
/**
* Valid font-display values.
*
* @since 6.4.0
*
* @var string[]
*/
private $valid_font_display = array( 'auto', 'block', 'fallback', 'swap', 'optional' );
/**
* Generates and prints the `@font-face` styles for the given fonts.
*
* @since 6.4.0
*
* @param array[][] $fonts Optional. The font-families and their font variations.
* See {@see wp_print_font_faces()} for the supported fields.
* Default empty array.
*/
public function generate_and_print( array $fonts ) {
$fonts = $this->validate_fonts( $fonts );
// Bail out if there are no fonts are given to process.
if ( empty( $fonts ) ) {
return;
}
$css = $this->get_css( $fonts );
/*
* The font-face CSS is contained within <style> tags and can only be interpreted
* as CSS in the browser. Using wp_strip_all_tags() is sufficient escaping
* to avoid malicious attempts to close </style> and open a <script>.
*/
$css = wp_strip_all_tags( $css );
// Bail out if there is no CSS to print.
if ( empty( $css ) ) {
return;
}
$processor = new WP_HTML_Tag_Processor( '<style class="wp-fonts-local"></style>' );
$processor->next_tag();
$processor->set_modifiable_text( "\n{$css}\n" );
echo "{$processor->get_updated_html()}\n";
}
/**
* Validates each of the font-face properties.
*
* @since 6.4.0
*
* @param array $fonts The fonts to valid.
* @return array Prepared font-faces organized by provider and font-family.
*/
private function validate_fonts( array $fonts ) {
$validated_fonts = array();
foreach ( $fonts as $font_faces ) {
foreach ( $font_faces as $font_face ) {
$font_face = $this->validate_font_face_declarations( $font_face );
// Skip if failed validation.
if ( false === $font_face ) {
continue;
}
$validated_fonts[] = $font_face;
}
}
return $validated_fonts;
}
/**
* Validates each font-face declaration (property and value pairing).
*
* @since 6.4.0
*
* @param array $font_face Font face property and value pairings to validate.
* @return array|false Validated font-face on success, or false on failure.
*/
private function validate_font_face_declarations( array $font_face ) {
$font_face = wp_parse_args( $font_face, $this->font_face_property_defaults );
// Check the font-family.
if ( empty( $font_face['font-family'] ) || ! is_string( $font_face['font-family'] ) ) {
// @todo replace with `wp_trigger_error()`.
_doing_it_wrong(
__METHOD__,
__( 'Font font-family must be a non-empty string.' ),
'6.4.0'
);
return false;
}
// Make sure that local fonts have 'src' defined.
if ( empty( $font_face['src'] ) || ( ! is_string( $font_face['src'] ) && ! is_array( $font_face['src'] ) ) ) {
// @todo replace with `wp_trigger_error()`.
_doing_it_wrong(
__METHOD__,
__( 'Font src must be a non-empty string or an array of strings.' ),
'6.4.0'
);
return false;
}
// Validate the 'src' property.
foreach ( (array) $font_face['src'] as $src ) {
if ( empty( $src ) || ! is_string( $src ) ) {
// @todo replace with `wp_trigger_error()`.
_doing_it_wrong(
__METHOD__,
__( 'Each font src must be a non-empty string.' ),
'6.4.0'
);
return false;
}
}
// Check the font-weight.
if ( ! is_string( $font_face['font-weight'] ) && ! is_int( $font_face['font-weight'] ) ) {
// @todo replace with `wp_trigger_error()`.
_doing_it_wrong(
__METHOD__,
__( 'Font font-weight must be a properly formatted string or integer.' ),
'6.4.0'
);
return false;
}
// Check the font-display.
if ( ! in_array( $font_face['font-display'], $this->valid_font_display, true ) ) {
$font_face['font-display'] = $this->font_face_property_defaults['font-display'];
}
// Remove invalid properties.
foreach ( $font_face as $property => $value ) {
if ( ! in_array( $property, $this->valid_font_face_properties, true ) ) {
unset( $font_face[ $property ] );
}
}
return $font_face;
}
/**
* Gets the `@font-face` CSS styles for locally-hosted font files.
*
* This method does the following processing tasks:
* 1. Orchestrates an optimized `src` (with format) for browser support.
* 2. Generates the `@font-face` for all its fonts.
*
* @since 6.4.0
*
* @param array[] $font_faces The font-faces to generate @font-face CSS styles.
* @return string The `@font-face` CSS styles.
*/
private function get_css( $font_faces ) {
$css = '';
foreach ( $font_faces as $font_face ) {
// Order the font's `src` items to optimize for browser support.
$font_face = $this->order_src( $font_face );
// Build the @font-face CSS for this font.
$css .= '@font-face{' . $this->build_font_face_css( $font_face ) . '}' . "\n";
}
// Don't print the last newline character.
return rtrim( $css, "\n" );
}
/**
* Orders `src` items to optimize for browser support.
*
* @since 6.4.0
*
* @param array $font_face Font face to process.
* @return array Font-face with ordered src items.
*/
private function order_src( array $font_face ) {
if ( ! is_array( $font_face['src'] ) ) {
$font_face['src'] = (array) $font_face['src'];
}
$src = array();
$src_ordered = array();
foreach ( $font_face['src'] as $url ) {
// Add data URIs first.
if ( str_starts_with( trim( $url ), 'data:' ) ) {
$src_ordered[] = array(
'url' => $url,
'format' => 'data',
);
continue;
}
$format = pathinfo( $url, PATHINFO_EXTENSION );
$src[ $format ] = $url;
}
// Add woff2.
if ( ! empty( $src['woff2'] ) ) {
$src_ordered[] = array(
'url' => $src['woff2'],
'format' => 'woff2',
);
}
// Add woff.
if ( ! empty( $src['woff'] ) ) {
$src_ordered[] = array(
'url' => $src['woff'],
'format' => 'woff',
);
}
// Add ttf.
if ( ! empty( $src['ttf'] ) ) {
$src_ordered[] = array(
'url' => $src['ttf'],
'format' => 'truetype',
);
}
// Add eot.
if ( ! empty( $src['eot'] ) ) {
$src_ordered[] = array(
'url' => $src['eot'],
'format' => 'embedded-opentype',
);
}
// Add otf.
if ( ! empty( $src['otf'] ) ) {
$src_ordered[] = array(
'url' => $src['otf'],
'format' => 'opentype',
);
}
$font_face['src'] = $src_ordered;
return $font_face;
}
/**
* Builds the font-family's CSS.
*
* @since 6.4.0
*
* @param array $font_face Font face to process.
* @return string This font-family's CSS.
*/
private function build_font_face_css( array $font_face ) {
$css = '';
/*
* Wrap font-family in quotes if it contains spaces
* and is not already wrapped in quotes.
*/
if (
str_contains( $font_face['font-family'], ' ' ) &&
! str_contains( $font_face['font-family'], '"' ) &&
! str_contains( $font_face['font-family'], "'" )
) {
$font_face['font-family'] = '"' . $font_face['font-family'] . '"';
}
foreach ( $font_face as $key => $value ) {
// Compile the "src" parameter.
if ( 'src' === $key ) {
$value = $this->compile_src( $value );
}
// If font-variation-settings is an array, convert it to a string.
if ( 'font-variation-settings' === $key && is_array( $value ) ) {
$value = $this->compile_variations( $value );
}
if ( ! empty( $value ) ) {
$css .= "$key:$value;";
}
}
return $css;
}
/**
* Compiles the `src` into valid CSS.
*
* @since 6.4.0
*
* @param array $value Value to process.
* @return string The CSS.
*/
private function compile_src( array $value ) {
$src = '';
foreach ( $value as $item ) {
$src .= ( 'data' === $item['format'] )
? ", url({$item['url']})"
: ", url('{$item['url']}') format('{$item['format']}')";
}
$src = ltrim( $src, ', ' );
return $src;
}
/**
* Compiles the font variation settings.
*
* @since 6.4.0
*
* @param array $font_variation_settings Array of font variation settings.
* @return string The CSS.
*/
private function compile_variations( array $font_variation_settings ) {
$variations = '';
foreach ( $font_variation_settings as $key => $value ) {
$variations .= "$key $value";
}
return $variations;
}
}