<?php
/**
 * Plugin Name:       AI Summarise Button
 * Plugin URI:        https://wordpress.org/plugins/ai-summarise-button/
 * Description:       Block and shortcode that opens the current page in the reader's chosen AI tool for summarising (ChatGPT in Basic mode, or an Advanced provider picker). Alignment, colour and size controls included.
 * Version:           3.0.0
 * Requires at least: 6.5
 * Requires PHP:      7.4
 * Author:            cropllm
 * License:           GPLv2 or later
 * License URI:       https://www.gnu.org/licenses/gpl-2.0.html
 * Text Domain:       ai-summarise-button
 *
 * @package AiSummariseButton
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

define( 'AISUBU_VER', '3.0.0' );
define( 'AISUBU_URL', plugin_dir_url( __FILE__ ) );
define( 'AISUBU_PATH', plugin_dir_path( __FILE__ ) );

/**
 * The AI tools the button can open.
 *
 * `query` is false for tools that cannot take a prompt in the URL — those are
 * opened bare and the page text goes on the clipboard instead (inc/frontend.js).
 *
 * @return array<string, array<string, mixed>>
 */
function aisubu_get_providers() {
	$providers = array(
		'chatgpt'    => array(
			'label' => __( 'ChatGPT', 'ai-summarise-button' ),
			'base'  => 'https://chatgpt.com/?hints=search&q=',
			'query' => true,
		),
		'perplexity' => array(
			'label' => __( 'Perplexity', 'ai-summarise-button' ),
			'base'  => 'https://www.perplexity.ai/?q=',
			'query' => true,
		),
		'copilot'    => array(
			'label' => __( 'Copilot', 'ai-summarise-button' ),
			'base'  => 'https://copilot.microsoft.com/?q=',
			'query' => true,
		),
		'claude'     => array(
			'label' => __( 'Claude', 'ai-summarise-button' ),
			'base'  => 'https://claude.ai/new',
			'query' => false,
		),
		'gemini'     => array(
			'label' => __( 'Gemini', 'ai-summarise-button' ),
			'base'  => 'https://gemini.google.com/app',
			'query' => false,
		),
	);

	/**
	 * Filters the available AI tools.
	 *
	 * @param array $providers Slug => array( label, base, query ).
	 */
	return apply_filters( 'aisubu_providers', $providers );
}

/**
 * Destination URL for a provider.
 *
 * @param string $provider Provider slug.
 * @param string $q        Prompt.
 * @return string
 */
function aisubu_provider_url( $provider, $q ) {
	$providers = aisubu_get_providers();
	$definition = isset( $providers[ $provider ] ) ? $providers[ $provider ] : $providers['chatgpt'];

	$url = $definition['query'] ? $definition['base'] . rawurlencode( $q ) : $definition['base'];

	/**
	 * Filters the destination URL for a provider.
	 *
	 * @param string $url      Destination URL.
	 * @param string $provider Provider slug.
	 * @param string $q        Prompt.
	 */
	return apply_filters( 'aisubu_provider_url', $url, $provider, $q );
}

/**
 * Builds the prompt sent to the AI tool.
 *
 * @param string $title Page title.
 * @param string $url   Page URL.
 * @param array  $attrs Prompt parts: qPrefix, noun, qSuffix.
 * @return string
 */
function aisubu_build_q( $title, $url, $attrs ) {
	$prefix = isset( $attrs['qPrefix'] ) ? $attrs['qPrefix'] : 'Read and summarise this';
	$noun   = isset( $attrs['noun'] ) ? $attrs['noun'] : 'page';
	$suffix = isset( $attrs['qSuffix'] ) ? $attrs['qSuffix'] : 'so I can ask questions about it.';
	$title  = trim( wp_strip_all_tags( (string) $title ) );

	$q = sprintf( '%s "%s" %s from %s %s', $prefix, $title, $noun, $url, $suffix );

	/**
	 * Filters the prompt.
	 *
	 * @param string $q     Prompt.
	 * @param string $title Page title.
	 * @param string $url   Page URL.
	 */
	return apply_filters( 'aisubu_prompt', $q, $title, $url );
}

/**
 * Default block attributes.
 *
 * @return array<string, mixed>
 */
function aisubu_get_defaults() {
	return array(
		'mode'         => 'basic',
		'buttonText'   => 'Summarise with AI',
		'qPrefix'      => 'Read and summarise this',
		'qSuffix'      => 'so I can ask questions about it.',
		'noun'         => 'page',
		'provider'     => 'chatgpt',
		'bgColor'      => '',
		'textColor'    => '',
		'borderColor'  => '',
		'borderRadius' => 8,
		'paddingX'     => 10,
		'paddingY'     => 6,
		'isFullWidth'  => false,
		'iconPosition' => 'left',
		'justify'      => 'left',
		'logoSize'     => 15,
		'maxWidth'     => 200,
		'maxHeight'    => 32,
		'preset'       => 'chatgpt',
		'openInNewTab' => true,
		'relNoFollow'  => true,
		'align'        => '',
	);
}

/**
 * Colour presets.
 *
 * @return array<string, array<string, string>>
 */
function aisubu_get_presets() {
	return array(
		'chatgpt' => array(
			'bg' => '#10A37F',
			'fg' => '#ffffff',
			'bd' => '#0D8667',
		),
		'outline' => array(
			'bg' => '#ffffff',
			'fg' => '#111827',
			'bd' => '#D1D5DB',
		),
		'dark'    => array(
			'bg' => '#111827',
			'fg' => '#ffffff',
			'bd' => '#1F2937',
		),
		'blue'    => array(
			'bg' => '#2563EB',
			'fg' => '#ffffff',
			'bd' => '#1E40AF',
		),
	);
}

/**
 * Accepts a hex, rgb() or rgba() colour; anything else falls back.
 *
 * @param string $colour   Candidate colour.
 * @param string $fallback Value returned when the candidate is not valid.
 * @return string
 */
function aisubu_safe_colour( $colour, $fallback = '' ) {
	$colour = trim( (string) $colour );

	if ( '' === $colour ) {
		return $fallback;
	}

	$hex = sanitize_hex_color( $colour );
	if ( $hex ) {
		return $hex;
	}

	if ( preg_match( '/^rgba?\(\s*\d{1,3}\s*,\s*\d{1,3}\s*,\s*\d{1,3}\s*(,\s*(0|1|0?\.\d+)\s*)?\)$/i', $colour ) ) {
		return $colour;
	}

	return $fallback;
}

/**
 * The inline sparkle logo. Uses currentColor so it follows the button text.
 *
 * @return string
 */
function aisubu_get_logo_svg() {
	return '<svg viewBox="0 0 24 24" fill="currentColor" aria-hidden="true" focusable="false" xmlns="http://www.w3.org/2000/svg">'
		. '<path d="M12 3 13.5 8.5 19 10 13.5 11.5 12 17 10.5 11.5 5 10 10.5 8.5Z"/>'
		. '<path d="M18.5 2 19.2 3.8 21 4.5 19.2 5.2 18.5 7 17.8 5.2 16 4.5 17.8 3.8Z"/>'
		. '</svg>';
}

/**
 * Registers shared assets. Runs before block registration.
 *
 * @return void
 */
function aisubu_register_assets() {
	wp_register_style( 'aisubu-frontend', AISUBU_URL . 'inc/frontend.css', array(), AISUBU_VER );

	wp_register_script(
		'aisubu-frontend',
		AISUBU_URL . 'inc/frontend.js',
		array(),
		AISUBU_VER,
		array(
			'strategy'  => 'defer',
			'in_footer' => true,
		)
	);

	wp_set_script_translations( 'aisubu-frontend', 'ai-summarise-button' );

	$providers = array();
	foreach ( aisubu_get_providers() as $slug => $definition ) {
		$providers[] = array(
			'value' => $slug,
			'label' => $definition['label'],
			'base'  => $definition['base'],
			'query' => (bool) $definition['query'],
		);
	}

	wp_localize_script(
		'aisubu-frontend',
		'aisubuData',
		array(
			'providers' => $providers,
			/**
			 * Filters which tools get the page text copied to the clipboard.
			 *
			 * @param array $slugs Provider slugs.
			 */
			'copyFor'   => apply_filters( 'aisubu_copy_page_for', array( 'perplexity', 'claude', 'gemini' ) ),
			'i18n'      => array(
				'title'    => __( 'Choose AI to summarise with', 'ai-summarise-button' ),
				'hint'     => __( 'For Perplexity, Claude and Gemini we’ll copy the page text for quick paste.', 'ai-summarise-button' ),
				'cancel'   => __( 'Cancel', 'ai-summarise-button' ),
				'continue' => __( 'Continue', 'ai-summarise-button' ),
				'copyFail' => __( 'Couldn’t copy; please paste manually.', 'ai-summarise-button' ),
			),
		)
	);

	wp_register_script(
		'aisubu-block',
		AISUBU_URL . 'block.js',
		array( 'wp-blocks', 'wp-element', 'wp-components', 'wp-block-editor', 'wp-i18n' ),
		AISUBU_VER,
		true
	);

	wp_set_script_translations( 'aisubu-block', 'ai-summarise-button' );
}
add_action( 'init', 'aisubu_register_assets', 5 );

/**
 * Registers the block from block.json.
 *
 * @return void
 */
function aisubu_register_block() {
	register_block_type(
		AISUBU_PATH . 'block.json',
		array( 'render_callback' => 'aisubu_render_button' )
	);
}
add_action( 'init', 'aisubu_register_block' );

/**
 * Loads front-end styles in the editor too, so the preview matches.
 *
 * @return void
 */
function aisubu_editor_assets() {
	wp_enqueue_style( 'aisubu-frontend' );
}
add_action( 'enqueue_block_editor_assets', 'aisubu_editor_assets' );

/**
 * Renders the button. Shared by the block and the shortcode.
 *
 * @param array $attributes Block attributes.
 * @return string
 */
function aisubu_render_button( $attributes ) {
	$a = wp_parse_args( is_array( $attributes ) ? $attributes : array(), aisubu_get_defaults() );

	wp_enqueue_style( 'aisubu-frontend' );

	$title = function_exists( 'wp_get_document_title' ) ? wp_get_document_title() : get_bloginfo( 'name' );
	$url   = home_url( '/' );

	if ( is_singular() ) {
		$maybe_title = get_the_title();
		if ( $maybe_title ) {
			$title = $maybe_title;
		}

		$maybe_url = get_permalink();
		if ( $maybe_url ) {
			$url = $maybe_url;
		}
	}

	$q = aisubu_build_q(
		$title,
		$url,
		array(
			'qPrefix' => sanitize_text_field( (string) $a['qPrefix'] ),
			'qSuffix' => sanitize_text_field( (string) $a['qSuffix'] ),
			'noun'    => sanitize_text_field( (string) $a['noun'] ),
		)
	);

	// Colours: an explicit colour wins, otherwise the preset, otherwise ChatGPT green.
	$presets = aisubu_get_presets();
	$preset  = isset( $presets[ $a['preset'] ] ) ? $presets[ $a['preset'] ] : $presets['chatgpt'];

	$bg = aisubu_safe_colour( $a['bgColor'] );
	$fg = aisubu_safe_colour( $a['textColor'] );
	$bd = aisubu_safe_colour( $a['borderColor'] );

	if ( 'custom' !== $a['preset'] && ! $bg && ! $fg && ! $bd ) {
		$bg = $preset['bg'];
		$fg = $preset['fg'];
		$bd = $preset['bd'];
	}

	$bg = $bg ? $bg : '#10A37F';
	$fg = $fg ? $fg : '#ffffff';
	$bd = $bd ? $bd : 'rgba(0,0,0,.08)';

	$radius     = max( 0, min( 60, absint( $a['borderRadius'] ) ) );
	$padding_x  = max( 0, min( 60, absint( $a['paddingX'] ) ) );
	$padding_y  = max( 0, min( 60, absint( $a['paddingY'] ) ) );
	$max_width  = max( 60, min( 1200, absint( $a['maxWidth'] ) ) );
	$max_height = max( 20, min( 120, absint( $a['maxHeight'] ) ) );
	$logo_size  = max( 8, min( 64, absint( $a['logoSize'] ) ) );

	$mode     = in_array( $a['mode'], array( 'basic', 'advanced' ), true ) ? $a['mode'] : 'basic';
	$justify  = in_array( $a['justify'], array( 'left', 'center', 'right' ), true ) ? $a['justify'] : 'left';
	$icon_pos = 'right' === $a['iconPosition'] ? 'right' : 'left';
	$provider = array_key_exists( $a['provider'], aisubu_get_providers() ) ? $a['provider'] : 'chatgpt';

	$rel    = $a['relNoFollow'] ? 'noopener nofollow' : 'noopener';
	$target = $a['openInNewTab'] ? '_blank' : '_self';

	$justify_content = 'flex-start';
	$text_align      = 'left';
	$auto_margin     = '';

	if ( 'center' === $justify ) {
		$justify_content = 'center';
		$text_align      = 'center';
		$auto_margin     = 'margin-left:auto;margin-right:auto;';
	} elseif ( 'right' === $justify ) {
		$justify_content = 'flex-end';
		$text_align      = 'right';
		$auto_margin     = 'margin-left:auto;';
	}

	$wrap_style = 'width:100%;display:flex;align-items:center;gap:.5rem;margin:.5rem 0;justify-content:' . $justify_content . ';text-align:' . $text_align . ';';

	$btn_style = $auto_margin
		. 'display:inline-flex;align-items:center;gap:0;'
		. 'border:1px solid ' . $bd . ';'
		. 'border-radius:' . $radius . 'px;'
		. 'background:' . $bg . ';color:' . $fg . ';'
		. 'text-decoration:none;line-height:1;'
		. 'max-width:' . $max_width . 'px;height:' . $max_height . 'px;'
		. 'padding:' . $padding_y . 'px ' . $padding_x . 'px;'
		. 'white-space:nowrap;overflow:hidden;';

	if ( $a['isFullWidth'] ) {
		$btn_style .= 'width:100%;justify-content:center;';
	}

	$icon_html = sprintf(
		'<span class="ai-summarise-logo-wrap"><span class="ai-summarise-logo%1$s" style="width:%2$dpx;height:%2$dpx">%3$s</span></span>',
		'right' === $icon_pos ? ' right' : '',
		$logo_size,
		aisubu_get_logo_svg()
	);

	$label_html = sprintf(
		'<span class="asb-label" style="line-height:1;text-overflow:ellipsis;overflow:hidden">%s</span>',
		esc_html( sanitize_text_field( (string) $a['buttonText'] ) )
	);

	$inner = 'right' === $icon_pos ? $label_html . $icon_html : $icon_html . $label_html;

	if ( 'basic' === $mode ) {
		$button = sprintf(
			'<a class="asb-button" style="%1$s" target="%2$s" rel="%3$s" href="%4$s">%5$s</a>',
			esc_attr( $btn_style ),
			esc_attr( $target ),
			esc_attr( $rel ),
			esc_url( aisubu_provider_url( 'chatgpt', $q ) ),
			$inner
		);
	} else {
		$button = sprintf(
			'<a class="asb-button" href="#" data-mode="advanced" data-q="%1$s" data-default="%2$s" style="%3$s" target="%4$s" rel="%5$s">%6$s</a>',
			esc_attr( $q ),
			esc_attr( $provider ),
			esc_attr( $btn_style ),
			esc_attr( $target ),
			esc_attr( $rel ),
			$inner
		);

		wp_enqueue_script( 'aisubu-frontend' );
	}

	return sprintf(
		'<div class="asb-wrap" style="%1$s">%2$s</div>',
		esc_attr( $wrap_style ),
		$button
	);
}

/**
 * Shortcode handler: [aisubu_summarise_button].
 *
 * @param array|string $atts Shortcode attributes.
 * @return string
 */
function aisubu_shortcode( $atts ) {
	$atts = shortcode_atts(
		array(
			'mode'        => 'basic',
			'text'        => 'Summarise with AI',
			'preset'      => 'chatgpt',
			'align'       => 'left',
			'width'       => '200',
			'height'      => '32',
			'logosize'    => '15',
			'qprefix'     => 'Read and summarise this',
			'qsuffix'     => 'so I can ask questions about it.',
			'noun'        => 'page',
			'provider'    => 'chatgpt',
			'newtab'      => '1',
			'nofollow'    => '1',
			'bgcolor'     => '',
			'textcolor'   => '',
			'bordercolor' => '',
		),
		$atts,
		'aisubu_summarise_button'
	);

	return aisubu_render_button(
		array(
			'mode'         => $atts['mode'],
			'buttonText'   => $atts['text'],
			'preset'       => $atts['preset'],
			'justify'      => $atts['align'],
			'maxWidth'     => (int) $atts['width'],
			'maxHeight'    => (int) $atts['height'],
			'logoSize'     => (int) $atts['logosize'],
			'qPrefix'      => $atts['qprefix'],
			'qSuffix'      => $atts['qsuffix'],
			'noun'         => $atts['noun'],
			'provider'     => $atts['provider'],
			'openInNewTab' => ( '1' === (string) $atts['newtab'] ),
			'relNoFollow'  => ( '1' === (string) $atts['nofollow'] ),
			'bgColor'      => $atts['bgcolor'],
			'textColor'    => $atts['textcolor'],
			'borderColor'  => $atts['bordercolor'],
		)
	);
}
add_shortcode( 'aisubu_summarise_button', 'aisubu_shortcode' );