<?php
if ( ! defined( 'ABSPATH' ) ) {
    exit;
}

class Admin_Hero_Feature_Loader {
    private $features = [];

    /**
     * Load feature definitions from Free + any additional directories.
     *
     * @param string $features_dir Absolute path to Free plugin’s features folder.
     */
    public function load_features( $features_dir ) {
        // 1) Gather directories to scan
        $dirs = [];

        // Always include Free’s own features folder if it exists
        if ( is_dir( $features_dir ) ) {
            $dirs[] = rtrim( $features_dir, '/\\' ) . '/';
        }

        // Include any extra feature directories (e.g. Pro) registered via filter
        $extra = apply_filters( 'admin_hero_feature_dirs', [] );
        if ( ! is_array( $extra ) ) {
            $extra = [ $extra ];
        }
        foreach ( $extra as $d ) {
            if ( is_string( $d ) && is_dir( $d ) ) {
                $dirs[] = rtrim( $d, '/\\' ) . '/';
            }
        }

        // If no valid directories, nothing to load
        if ( empty( $dirs ) ) {
            return;
        }

        // 2) Include every PHP file in each feature subdirectory
        foreach ( $dirs as $dir ) {
            foreach ( glob( $dir . '*/{index.php,*.php}', GLOB_BRACE ) as $feature_file ) {
                include_once $feature_file;
            }
        }

        // 3) Collect all features registered via the filter
        $this->features = apply_filters( 'admin_hero_features', [] );

        // 4) Validate & initialize each feature
        foreach ( $this->features as $index => &$feature ) {
            if ( ! $this->validate_feature( $feature ) ) {
                unset( $this->features[ $index ] );
                continue;
            }
            $this->initialize_feature( $feature, $index );
        }
        unset( $feature );

        // 5) Sort by priority
        usort( $this->features, function( $a, $b ) {
            return ( $a['priority'] ?? 50 ) <=> ( $b['priority'] ?? 50 );
        } );
    }

    /**
     * Ensure a feature has the required structure.
     */
    private function validate_feature( $feature ) {
        if ( ! is_array( $feature ) || empty( $feature['id'] ) || empty( $feature['name'] ) ) {
            return false;
        }
        $feature['id']                = sanitize_key( $feature['id'] );
        $feature['name']              = sanitize_text_field( $feature['name'] );
        $feature['priority']          = absint( $feature['priority'] ?? 50 );
        $feature['settings']          = (array) ( $feature['settings'] ?? [] );
        $feature['sanitize_callback'] = $feature['sanitize_callback'] ?? 'sanitize_text_field';
        return true;
    }

    /**
     * Initialize a single feature: set enabled state, enqueue assets, register settings UI.
     */
    private function initialize_feature( &$feature, $index ) {
        $user_id = get_current_user_id();
        $saved   = get_user_meta( $user_id, "admin_hero_feature_{$feature['id']}", true );
        $feature['enabled'] = ( $saved !== '' ) ? (bool) $saved : false;
        $this->features[ $index ] = $feature;

        // 1) Enqueue callbacks if provided
        if ( ! empty( $feature['enqueue_callback'] ) && is_callable( $feature['enqueue_callback'] ) ) {
            add_action( 'admin_enqueue_scripts', $feature['enqueue_callback'] );
            add_action( 'wp_enqueue_scripts',    $feature['enqueue_callback'] );
        }
        // 2) Otherwise automatically enqueue any versioned CSS/JS in /assets/
        else {
            // CSS
            $css_pattern = ADMIN_HERO_DIR . "features/{$feature['id']}/assets/{$feature['id']}*.css";
            $css_files   = glob( $css_pattern );
            if ( $css_files ) {
                rsort( $css_files );
                $css_file = basename( $css_files[0] );
                $callback = function() use ( $feature, $css_file ) {
                    wp_enqueue_style(
                        "admin-hero-{$feature['id']}",
                        ADMIN_HERO_URL . "features/{$feature['id']}/assets/{$css_file}",
                        [ 'admin-hero-css' ],
                        ADMIN_HERO_VERSION
                    );
                };
                add_action( 'admin_enqueue_scripts', $callback );
                add_action( 'wp_enqueue_scripts',    $callback );
            }

            // JS
            $js_pattern = ADMIN_HERO_DIR . "features/{$feature['id']}/assets/{$feature['id']}*.js";
            $js_files   = glob( $js_pattern );
            if ( $js_files ) {
                rsort( $js_files );
                $js_file = basename( $js_files[0] );
                $callback = function() use ( $feature, $js_file ) {
                    wp_enqueue_script(
                        "admin-hero-{$feature['id']}",
                        ADMIN_HERO_URL . "features/{$feature['id']}/assets/{$js_file}",
                        [ 'admin-hero-js' ],
                        ADMIN_HERO_VERSION,
                        true
                    );
                };
                add_action( 'admin_enqueue_scripts', $callback );
                add_action( 'wp_enqueue_scripts',    $callback );
            }
        }

        // 3) Register settings UI *only* if it's not the “info” feature
        if ( $feature['id'] !== 'info' ) {
            if ( ! empty( $feature['settings_ui_callback'] ) && is_callable( $feature['settings_ui_callback'] ) ) {
                add_action( 'admin_hero_settings_ui', $feature['settings_ui_callback'] );
            } else {
                $tmpl = ADMIN_HERO_DIR . "features/{$feature['id']}/templates/settings.php";
                if ( file_exists( $tmpl ) ) {
                    add_action( 'admin_hero_settings_ui', function() use ( $tmpl ) {
                        include $tmpl;
                    } );
                }
            }
        }
    }

    /**
     * Return all loaded features.
     *
     * @return array
     */
    public function get_features() {
        return $this->features;
    }

    /**
     * Return a single feature by ID or null.
     */
    public function get_feature( $feature_id ) {
        foreach ( $this->features as $f ) {
            if ( $f['id'] === $feature_id ) {
                return $f;
            }
        }
        return null;
    }
}