<?php
/**
 * Admin settings registration.
 *
 * @package Plectrum
 */

namespace DA_Plectrum;

defined( 'ABSPATH' ) || exit;

/**
 * Registers and renders the plugin settings UI.
 */
class Settings {
	/**
	 * Settings page hook suffix.
	 *
	 * @var string|null
	 */
	private $page_hook = null;

	/**
	 * Get default settings.
	 *
	 * @return array<string, mixed>
	 */
	public static function get_default_settings() {
		$defaults = array(
			'automatic_processing'   => false,
			'enabled_post_types'     => array( 'post', 'page' ),
			'enable_diagrams'        => true,
			'diagram_mode'           => 'compact',
			'default_diagram_width'  => 20,
			'default_song_scale'     => 1,
			'chord_prompt_font_size' => 14,
			'block_spacing'          => 12,
			'section_break_spacing'  => 24,
			'show_controls'          => true,
			'enable_print_button'    => true,
			'print_show_diagrams'    => true,
			'default_tuning'         => 'gCEA',
			'enharmonic_preference'  => 'auto',
			'print_footer_notice'    => '',
			'remove_on_uninstall'    => false,
		);

		return apply_filters( 'da_plectrum_default_settings', $defaults );
	}

	/**
	 * Register plugin settings.
	 *
	 * @return void
	 */
	public function register_settings() {
		register_setting(
			'da_plectrum_settings_group',
			DA_PLECTRUM_OPTION_KEY,
			array(
				'type'              => 'array',
				'sanitize_callback' => array( $this, 'sanitize_settings' ),
				'default'           => self::get_default_settings(),
			)
		);

		add_settings_section(
			'da_plectrum_general',
			__( 'General', 'plectrum' ),
			'__return_empty_string',
			'da-plectrum-settings'
		);

		add_settings_field(
			'automatic_processing',
			__( 'Enable automatic processing', 'plectrum' ),
			array( $this, 'render_checkbox_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'automatic_processing',
				'description' => __( 'Automatically process chord-marked content on selected post types.', 'plectrum' ),
			)
		);

		add_settings_field(
			'enabled_post_types',
			__( 'Enabled post types', 'plectrum' ),
			array( $this, 'render_post_types_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'enabled_post_types',
				'description' => __( 'Choose which public post types should be processed automatically when enabled.', 'plectrum' ),
			)
		);

		add_settings_field(
			'show_controls',
			__( 'Show controls by default', 'plectrum' ),
			array( $this, 'render_checkbox_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'show_controls',
				'description' => __( 'Display transpose, size, and print controls when available.', 'plectrum' ),
			)
		);

		add_settings_field(
			'enable_diagrams',
			__( 'Enable diagrams', 'plectrum' ),
			array( $this, 'render_checkbox_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'enable_diagrams',
				'description' => __( 'Allow chord diagrams to be shown in rendered songs.', 'plectrum' ),
			)
		);

		add_settings_field(
			'diagram_mode',
			__( 'Default diagram mode', 'plectrum' ),
			array( $this, 'render_select_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'diagram_mode',
				'options'     => array(
					'compact' => __( 'Chord names with compact diagrams', 'plectrum' ),
					'names'   => __( 'Chord names only', 'plectrum' ),
				),
				'description' => __( 'Choose the initial display mode for chord diagrams.', 'plectrum' ),
			)
		);

		add_settings_field(
			'default_diagram_width',
			__( 'Default diagram width', 'plectrum' ),
			array( $this, 'render_number_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'default_diagram_width',
				'min'         => 12,
				'max'         => 80,
				'step'        => 1,
				'suffix'      => __( 'px', 'plectrum' ),
				'description' => __( 'Sets the default chord diagram width in pixels before any visitor adjustments.', 'plectrum' ),
			)
		);

		add_settings_field(
			'default_song_scale',
			__( 'Default chord/lyric size', 'plectrum' ),
			array( $this, 'render_number_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'default_song_scale',
				'min'         => 0.75,
				'max'         => 1.75,
				'step'        => 0.05,
				'description' => __( 'Sets the starting display scale for rendered chord sheets. Use 1 for the standard size.', 'plectrum' ),
			)
		);

		add_settings_field(
			'chord_prompt_font_size',
			__( 'Chord prompt font size', 'plectrum' ),
			array( $this, 'render_number_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'chord_prompt_font_size',
				'min'         => 8,
				'max'         => 48,
				'step'        => 1,
				'suffix'      => __( 'px', 'plectrum' ),
				'description' => __( 'Sets the font size for chord prompts such as G7, Am, F, and D7.', 'plectrum' ),
			)
		);

		add_settings_field(
			'block_spacing',
			__( 'Content block spacing', 'plectrum' ),
			array( $this, 'render_number_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'block_spacing',
				'min'         => 0,
				'max'         => 80,
				'step'        => 1,
				'suffix'      => __( 'px', 'plectrum' ),
				'description' => __( 'Sets the default top margin between adjacent content blocks.', 'plectrum' ),
			)
		);

		add_settings_field(
			'section_break_spacing',
			__( 'Section break spacing', 'plectrum' ),
			array( $this, 'render_number_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'section_break_spacing',
				'min'         => 0,
				'max'         => 120,
				'step'        => 1,
				'suffix'      => __( 'px', 'plectrum' ),
				'description' => __( 'Sets the larger top margin used after blank lines in the source content.', 'plectrum' ),
			)
		);

		add_settings_field(
			'enharmonic_preference',
			__( 'Enharmonic preference', 'plectrum' ),
			array( $this, 'render_select_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'enharmonic_preference',
				'options'     => array(
					'auto'            => __( 'Automatic', 'plectrum' ),
					'preserve-source' => __( 'Preserve source spelling', 'plectrum' ),
					'sharps'          => __( 'Prefer sharps', 'plectrum' ),
					'flats'           => __( 'Prefer flats', 'plectrum' ),
				),
				'description' => __( 'Choose how transposed chord names should prefer sharp or flat spellings.', 'plectrum' ),
			)
		);

		add_settings_field(
			'enable_print_button',
			__( 'Enable print button', 'plectrum' ),
			array( $this, 'render_checkbox_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'enable_print_button',
				'description' => __( 'Show a print button in the song controls.', 'plectrum' ),
			)
		);

		add_settings_field(
			'print_show_diagrams',
			__( 'Show diagrams in print', 'plectrum' ),
			array( $this, 'render_checkbox_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'print_show_diagrams',
				'description' => __( 'Include chord diagrams when printing song content.', 'plectrum' ),
			)
		);

		add_settings_field(
			'print_footer_notice',
			__( 'Print footer notice', 'plectrum' ),
			array( $this, 'render_textarea_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'print_footer_notice',
				'description' => __( 'Optional notice appended to printed output. Supports {year}, {site_name}, {post_title}, and {author}.', 'plectrum' ),
			)
		);

		add_settings_field(
			'remove_on_uninstall',
			__( 'Remove settings on uninstall', 'plectrum' ),
			array( $this, 'render_checkbox_field' ),
			'da-plectrum-settings',
			'da_plectrum_general',
			array(
				'key'         => 'remove_on_uninstall',
				'description' => __( 'Delete plugin settings when the plugin is uninstalled.', 'plectrum' ),
			)
		);
	}

	/**
	 * Register settings page.
	 *
	 * @return void
	 */
	public function register_settings_page() {
		$this->page_hook = add_menu_page(
			__( 'Plectrum', 'plectrum' ),
			__( 'Plectrum', 'plectrum' ),
			'manage_options',
			'da-plectrum',
			array( $this, 'render_settings_page' ),
			'dashicons-format-audio',
			58
		);
	}

	/**
	 * Render settings page.
	 *
	 * @return void
	 */
	public function render_settings_page() {
		if ( ! current_user_can( 'manage_options' ) ) {
			return;
		}

		$markup_example = implode(
			"\n",
			array(
				'[ukulele_chords]',
				'A[Dm]las my love, you [C]do me wrong',
				'To [Dm]cast me off dis[A]courteously;',
				'And [Dm]I have loved you [C]oh so long,',
				'De[Dm]lighting in [A7]your compa[D]ny,',
				'[/ukulele_chords]',
			)
		);
		?>
		<div class="wrap">
			<h1><?php esc_html_e( 'Plectrum', 'plectrum' ); ?></h1>
			<form action="options.php" method="post">
				<?php
				settings_fields( 'da_plectrum_settings_group' );
				do_settings_sections( 'da-plectrum-settings' );
				submit_button();
				?>
			</form>
			<section class="card da-plectrum-instructions" aria-labelledby="da-plectrum-instructions-title">
				<h2 id="da-plectrum-instructions-title"><?php esc_html_e( 'How to add chords to lyrics', 'plectrum' ); ?></h2>
				<ol>
					<li><?php esc_html_e( 'In the block editor, add a Shortcode block to your post or page. In the Classic Editor, enter the markup in the Text tab.', 'plectrum' ); ?></li>
					<li><?php esc_html_e( 'Wrap your lyrics in [ukulele_chords] and [/ukulele_chords].', 'plectrum' ); ?></li>
					<li><?php esc_html_e( 'Put each chord in square brackets immediately before the syllable where it changes. For example, A[Dm]las places Dm above “las”.', 'plectrum' ); ?></li>
					<li><?php esc_html_e( 'Keep each lyric line on its own line. Use a blank line between verses, then preview your post to check the chord placement.', 'plectrum' ); ?></li>
				</ol>
				<h3><?php esc_html_e( 'Example: Greensleeves', 'plectrum' ); ?></h3>
				<pre class="da-plectrum-markup-example"><code><?php echo esc_html( $markup_example ); ?></code></pre>
			</section>
			<section class="card da-plectrum-disclaimer" aria-labelledby="da-plectrum-disclaimer-title">
				<h2 id="da-plectrum-disclaimer-title"><?php esc_html_e( 'Disclaimer', 'plectrum' ); ?></h2>
				<p><?php esc_html_e( 'THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.', 'plectrum' ); ?></p>
				<p><?php esc_html_e( 'IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.', 'plectrum' ); ?></p>
			</section>
		</div>
		<?php
	}

	/**
	 * Sanitize settings values.
	 *
	 * @param array<string, mixed> $input Raw input.
	 * @return array<string, mixed>
	 */
	public function sanitize_settings( $input ) {
		$defaults = self::get_default_settings();
		$output   = array();

		$output['automatic_processing']   = ! empty( $input['automatic_processing'] );
		$output['enabled_post_types']     = $this->sanitize_post_types( $input['enabled_post_types'] ?? array() );
		$output['show_controls']          = ! empty( $input['show_controls'] );
		$output['enable_diagrams']        = ! empty( $input['enable_diagrams'] );
		$output['enable_print_button']    = ! empty( $input['enable_print_button'] );
		$output['print_show_diagrams']    = ! empty( $input['print_show_diagrams'] );
		$output['remove_on_uninstall']    = ! empty( $input['remove_on_uninstall'] );
		$output['diagram_mode']           = in_array( $input['diagram_mode'] ?? '', array( 'compact', 'names' ), true ) ? $input['diagram_mode'] : $defaults['diagram_mode'];
		$output['default_diagram_width']  = $this->sanitize_diagram_width( $input['default_diagram_width'] ?? $defaults['default_diagram_width'] );
		$output['default_song_scale']     = $this->sanitize_song_scale( $input['default_song_scale'] ?? $defaults['default_song_scale'] );
		$output['chord_prompt_font_size'] = $this->sanitize_chord_prompt_font_size( $input['chord_prompt_font_size'] ?? $defaults['chord_prompt_font_size'] );
		$output['block_spacing']          = $this->sanitize_spacing( $input['block_spacing'] ?? $defaults['block_spacing'], 80 );
		$output['section_break_spacing']  = $this->sanitize_spacing( $input['section_break_spacing'] ?? $defaults['section_break_spacing'], 120 );
		$output['default_tuning']         = 'gCEA';
		$output['enharmonic_preference']  = in_array( $input['enharmonic_preference'] ?? '', array( 'auto', 'preserve-source', 'sharps', 'flats' ), true ) ? $input['enharmonic_preference'] : $defaults['enharmonic_preference'];
		$output['print_footer_notice']    = sanitize_textarea_field( $input['print_footer_notice'] ?? '' );

		return wp_parse_args( $output, $defaults );
	}

	/**
	 * Get supported public post types.
	 *
	 * @return array<string, \WP_Post_Type>
	 */
	public function get_supported_post_types() {
		$post_types = get_post_types(
			array(
				'public' => true,
			),
			'objects'
		);

		unset( $post_types['attachment'] );

		return apply_filters( 'da_plectrum_supported_post_types', $post_types );
	}

	/**
	 * Sanitize selected automatic-processing post types.
	 *
	 * @param mixed $raw_post_types Raw post type values.
	 * @return array<int, string>
	 */
	private function sanitize_post_types( $raw_post_types ) {
		$selected = is_array( $raw_post_types ) ? $raw_post_types : array();
		$allowed  = array_keys( $this->get_supported_post_types() );

		return array_values( array_intersect( array_map( 'sanitize_key', $selected ), $allowed ) );
	}

	/**
	 * Sanitize the default diagram width.
	 *
	 * @param mixed $value Raw width value.
	 * @return int
	 */
	private function sanitize_diagram_width( $value ) {
		$width = absint( $value );

		if ( $width < 12 ) {
			return 12;
		}

		if ( $width > 80 ) {
			return 80;
		}

		return $width;
	}

	/**
	 * Sanitize the default song scale.
	 *
	 * @param mixed $value Raw scale value.
	 * @return float
	 */
	private function sanitize_song_scale( $value ) {
		$scale = is_numeric( $value ) ? (float) $value : 1;
		$scale = max( 0.75, min( 1.75, $scale ) );

		return round( $scale, 2 );
	}

	/**
	 * Sanitize the chord prompt font size.
	 *
	 * @param mixed $value Raw font size value.
	 * @return int
	 */
	private function sanitize_chord_prompt_font_size( $value ) {
		$size = absint( $value );

		if ( $size < 8 ) {
			return 8;
		}

		if ( $size > 48 ) {
			return 48;
		}

		return $size;
	}

	/**
	 * Sanitize spacing values.
	 *
	 * @param mixed $value Raw spacing value.
	 * @param int   $max Maximum allowed value.
	 * @return int
	 */
	private function sanitize_spacing( $value, $max ) {
		$spacing = absint( $value );

		if ( $spacing > $max ) {
			return $max;
		}

		return $spacing;
	}

	/**
	 * Enqueue assets for the plugin settings screen.
	 *
	 * @param string $hook_suffix Current admin page hook suffix.
	 * @return void
	 */
	public function enqueue_admin_assets( $hook_suffix ) {
		if ( $this->page_hook !== $hook_suffix ) {
			return;
		}

		wp_enqueue_style( 'da-plectrum-admin' );
		wp_enqueue_script( 'da-plectrum-admin' );
	}

	/**
	 * Get a setting.
	 *
	 * @param string $key Setting key.
	 * @return mixed
	 */
	public function get( $key ) {
		$settings = get_option( DA_PLECTRUM_OPTION_KEY, array() );
		$defaults = self::get_default_settings();

		return $settings[ $key ] ?? $defaults[ $key ] ?? null;
	}

	/**
	 * Render checkbox field.
	 *
	 * @param array<string, mixed> $args Field args.
	 * @return void
	 */
	public function render_checkbox_field( $args ) {
		$settings = get_option( DA_PLECTRUM_OPTION_KEY, self::get_default_settings() );
		$key      = $args['key'];
		$value    = ! empty( $settings[ $key ] );
		?>
		<label>
			<input type="checkbox" name="<?php echo esc_attr( DA_PLECTRUM_OPTION_KEY . '[' . $key . ']' ); ?>" value="1" <?php checked( $value ); ?> />
			<?php if ( ! empty( $args['description'] ) ) : ?>
				<span><?php echo esc_html( $args['description'] ); ?></span>
			<?php endif; ?>
		</label>
		<?php
	}

	/**
	 * Render select field.
	 *
	 * @param array<string, mixed> $args Field args.
	 * @return void
	 */
	public function render_select_field( $args ) {
		$settings = get_option( DA_PLECTRUM_OPTION_KEY, self::get_default_settings() );
		$key      = $args['key'];
		$value    = $settings[ $key ] ?? '';
		?>
		<select name="<?php echo esc_attr( DA_PLECTRUM_OPTION_KEY . '[' . $key . ']' ); ?>">
			<?php foreach ( $args['options'] as $option_value => $label ) : ?>
				<option value="<?php echo esc_attr( $option_value ); ?>" <?php selected( $value, $option_value ); ?>>
					<?php echo esc_html( $label ); ?>
				</option>
			<?php endforeach; ?>
		</select>
		<?php if ( ! empty( $args['description'] ) ) : ?>
			<p class="description"><?php echo esc_html( $args['description'] ); ?></p>
		<?php endif; ?>
		<?php
	}

	/**
	 * Render textarea field.
	 *
	 * @param array<string, mixed> $args Field args.
	 * @return void
	 */
	public function render_textarea_field( $args ) {
		$settings = get_option( DA_PLECTRUM_OPTION_KEY, self::get_default_settings() );
		$key      = $args['key'];
		$value    = $settings[ $key ] ?? '';
		?>
		<textarea
			name="<?php echo esc_attr( DA_PLECTRUM_OPTION_KEY . '[' . $key . ']' ); ?>"
			rows="4"
			cols="50"
			class="large-text"
		><?php echo esc_textarea( $value ); ?></textarea>
		<?php if ( ! empty( $args['description'] ) ) : ?>
			<p class="description"><?php echo esc_html( $args['description'] ); ?></p>
		<?php endif; ?>
		<?php
	}

	/**
	 * Render number field.
	 *
	 * @param array<string, mixed> $args Field args.
	 * @return void
	 */
	public function render_number_field( $args ) {
		$settings = get_option( DA_PLECTRUM_OPTION_KEY, self::get_default_settings() );
		$key      = $args['key'];
		$value    = $settings[ $key ] ?? '';
		?>
		<input
			type="number"
			name="<?php echo esc_attr( DA_PLECTRUM_OPTION_KEY . '[' . $key . ']' ); ?>"
			value="<?php echo esc_attr( (string) $value ); ?>"
			<?php if ( isset( $args['min'] ) ) : ?>
				min="<?php echo esc_attr( (string) $args['min'] ); ?>"
			<?php endif; ?>
			<?php if ( isset( $args['max'] ) ) : ?>
				max="<?php echo esc_attr( (string) $args['max'] ); ?>"
			<?php endif; ?>
			<?php if ( isset( $args['step'] ) ) : ?>
				step="<?php echo esc_attr( (string) $args['step'] ); ?>"
			<?php endif; ?>
			class="small-text"
		/>
		<?php if ( ! empty( $args['suffix'] ) ) : ?>
			<span><?php echo esc_html( $args['suffix'] ); ?></span>
		<?php endif; ?>
		<?php if ( ! empty( $args['description'] ) ) : ?>
			<p class="description"><?php echo esc_html( $args['description'] ); ?></p>
		<?php endif; ?>
		<?php
	}

	/**
	 * Render post type checkbox field.
	 *
	 * @param array<string, mixed> $args Field args.
	 * @return void
	 */
	public function render_post_types_field( $args ) {
		$settings       = get_option( DA_PLECTRUM_OPTION_KEY, self::get_default_settings() );
		$key            = $args['key'];
		$selected_types = isset( $settings[ $key ] ) && is_array( $settings[ $key ] ) ? $settings[ $key ] : array();
		$post_types     = $this->get_supported_post_types();

		foreach ( $post_types as $post_type ) :
			?>
			<label>
				<input
					type="checkbox"
					name="<?php echo esc_attr( DA_PLECTRUM_OPTION_KEY . '[' . $key . '][]' ); ?>"
					value="<?php echo esc_attr( $post_type->name ); ?>"
					<?php checked( in_array( $post_type->name, $selected_types, true ) ); ?>
				/>
				<span><?php echo esc_html( $post_type->labels->singular_name ); ?></span>
			</label><br />
			<?php
		endforeach;

		if ( ! empty( $args['description'] ) ) :
			?>
			<p class="description"><?php echo esc_html( $args['description'] ); ?></p>
			<?php
		endif;
	}
}