<?php

namespace AcademicCrew\Members;

use AcademicCrew\Core\ColorMath;

/**
 * Registry of AcademicCrew member roles — admin-configurable in
 * Settings → Member Roles (rename, recolor, delete, add), seeded with the
 * built-in defaults below on first use.
 *
 * Keys are stable slugs stored in _acc_member_role and must never change
 * once created — renaming only changes the display label.
 */
class RoleRegistry {

    private const OPTION = 'academiccrew_member_roles';

    /**
     * Built-in defaults, used until the admin customizes the list.
     * @return array<string,array{label:string,dot:string,bg:string,text:string}>
     */
    private static function default_entries(): array {
        $former = [ 'dot' => '#9CA3AF', 'bg' => '#F3F4F6', 'text' => '#6B7280' ];
        return [
            // Active members
            'full-professor'      => [ 'label' => __( 'Full Professor', 'academiccrew' ), 'dot' => '#c41230', 'bg' => '#FCEBEB', 'text' => '#A32D2D' ],
            'associate-professor' => [ 'label' => __( 'Associate Professor', 'academiccrew' ), 'dot' => '#185FA5', 'bg' => '#E6F1FB', 'text' => '#0C447C' ],
            'assistant-professor' => [ 'label' => __( 'Assistant Professor', 'academiccrew' ), 'dot' => '#3B6D11', 'bg' => '#EAF3DE', 'text' => '#3B6D11' ],
            'researcher'          => [ 'label' => __( 'Researcher', 'academiccrew' ), 'dot' => '#0F6E56', 'bg' => '#E1F5EE', 'text' => '#085041' ],
            'postdoc'             => [ 'label' => __( 'Postdoctoral Researcher', 'academiccrew' ), 'dot' => '#854F0B', 'bg' => '#FAEEDA', 'text' => '#854F0B' ],
            'phd-student'         => [ 'label' => __( 'PhD Student', 'academiccrew' ), 'dot' => '#534AB7', 'bg' => '#EEEDFE', 'text' => '#3C3489' ],
            'research-assistant'  => [ 'label' => __( 'Research Assistant', 'academiccrew' ), 'dot' => '#6B4D99', 'bg' => '#F0ECFB', 'text' => '#4A2E8A' ],
            'visiting-researcher' => [ 'label' => __( 'Visiting Researcher', 'academiccrew' ), 'dot' => '#B45309', 'bg' => '#FEF3C7', 'text' => '#92400E' ],
            'collaborator'        => [ 'label' => __( 'Collaborator', 'academiccrew' ), 'dot' => '#5F5E5A', 'bg' => '#F1EFE8', 'text' => '#444441' ],
            // Former members
            'former-professor'          => array_merge( [ 'label' => __( 'Former Professor', 'academiccrew' ) ], $former ),
            'former-researcher'         => array_merge( [ 'label' => __( 'Former Researcher', 'academiccrew' ) ], $former ),
            'former-postdoc'            => array_merge( [ 'label' => __( 'Former Postdoctoral Researcher', 'academiccrew' ) ], $former ),
            'former-phd'                => array_merge( [ 'label' => __( 'Former PhD Student', 'academiccrew' ) ], $former ),
            'former-research-assistant' => array_merge( [ 'label' => __( 'Former Research Assistant', 'academiccrew' ) ], $former ),
            'alumni'                    => array_merge( [ 'label' => __( 'Alumni', 'academiccrew' ) ], $former ),
        ];
    }

    /** @return array<string,array{label:string,dot:string,bg:string,text:string}> */
    private static function entries(): array {
        $stored = get_option( self::OPTION, null );
        return is_array( $stored ) ? $stored : self::default_entries();
    }

    /** @return array<string, string>  slug => translated label */
    public static function all(): array {
        return array_map( static fn( array $e ): string => $e['label'], self::entries() );
    }

    /**
     * @return array<string, array{dot: string, bg: string, text: string}>
     */
    public static function colors(): array {
        return array_map(
            static fn( array $e ): array => [ 'dot' => $e['dot'], 'bg' => $e['bg'], 'text' => $e['text'] ],
            self::entries()
        );
    }

    public static function label( string $key ): string {
        return self::all()[ $key ] ?? $key;
    }

    /** Returns the dot/accent hex color for a role. */
    public static function color( string $key ): string {
        return self::colors()[ $key ]['dot'] ?? '#6b7280';
    }

    /** Returns only the role slugs, without labels. */
    public static function keys(): array {
        return array_keys( self::all() );
    }

    /**
     * Derives bg/text shades from a single accent color — used when saving
     * a role the admin recolored or a brand new one.
     * @return array{dot:string,bg:string,text:string}
     */
    public static function shades_from_dot( string $dot ): array {
        return [
            'dot'  => $dot,
            'bg'   => ColorMath::tint( $dot ),
            'text' => ColorMath::shade( $dot ),
        ];
    }

    /** @param array<string,array{label:string,dot:string,bg:string,text:string}> $entries */
    public static function save( array $entries ): void {
        update_option( self::OPTION, $entries );
    }

    /** Number of members currently assigned to $slug. */
    public static function usage_count( string $slug ): int {
        $query = new \WP_Query( [
            'post_type'      => 'academiccrew_member',
            'post_status'    => 'any',
            'posts_per_page' => 1,
            'fields'         => 'ids',
            'no_found_rows'  => false,
            'meta_query'     => [ [ 'key' => '_acc_member_role', 'value' => $slug ] ], // phpcs:ignore WordPress.DB.SlowDBQuery
        ] );
        return (int) $query->found_posts;
    }
}