<?php
/**
 * Base REST Controller
 *
 * Extends WP_REST_Controller to provide shared helpers for all
 * Schema AI REST API endpoints.
 *
 * @package    Schema_AI
 * @subpackage Schema_AI/includes/api
 * @since      1.0.0
 */

if ( ! defined( 'ABSPATH' ) ) {
    exit;
}

class Schema_AI_REST_Controller extends WP_REST_Controller {

    /**
     * API namespace.
     *
     * @var string
     */
    protected $namespace = 'ai-schema-gen/v1';

    /**
     * Validate that a post ID references an existing, published-or-draft post.
     *
     * @param int $post_id The WordPress post ID.
     * @return true|WP_Error True when valid, WP_Error otherwise.
     */
    protected function validate_post_id( $post_id ) {
        $post_id = absint( $post_id );

        if ( ! $post_id ) {
            return new WP_Error(
                'schema_ai_invalid_post_id',
                __( 'Invalid post ID.', 'ai-schema-gen' ),
                array( 'status' => 400 )
            );
        }

        $post = get_post( $post_id );

        if ( ! $post ) {
            return new WP_Error(
                'schema_ai_post_not_found',
                __( 'Post not found.', 'ai-schema-gen' ),
                array( 'status' => 404 )
            );
        }

        return true;
    }

    /**
     * Prepare a raw database schema row for API response.
     *
     * @param object $schema Database row from the schemas table.
     * @return array Formatted schema data.
     */
    protected function prepare_schema_response( $schema ) {
        return array(
            'id'                => (int) $schema->id,
            'post_id'           => (int) $schema->post_id,
            'schema_type'       => $schema->schema_type,
            'schema_data'       => json_decode( $schema->schema_data, true ),
            'is_auto_generated' => (bool) $schema->is_auto_generated,
            'confidence_score'  => $schema->confidence_score ? (float) $schema->confidence_score : null,
            'validation_status' => $schema->validation_status,
            'validation_errors' => $schema->validation_errors ? json_decode( $schema->validation_errors, true ) : null,
            'last_validated'    => $schema->last_validated,
            'created_at'        => $schema->created_at,
            'updated_at'        => $schema->updated_at,
        );
    }

    /**
     * Check whether the current user can edit the given post.
     *
     * @param int $post_id The WordPress post ID.
     * @return true|WP_Error True when allowed, WP_Error otherwise.
     */
    protected function check_edit_permission( $post_id ) {
        if ( ! is_user_logged_in() ) {
            return new WP_Error(
                'schema_ai_not_logged_in',
                __( 'You must be logged in.', 'ai-schema-gen' ),
                array( 'status' => 401 )
            );
        }

        if ( ! current_user_can( 'edit_post', $post_id ) ) {
            return new WP_Error(
                'schema_ai_forbidden',
                __( 'You do not have permission to edit this post.', 'ai-schema-gen' ),
                array( 'status' => 403 )
            );
        }

        return true;
    }

    /**
     * Get the current user's subscription plan.
     *
     * @return string Plan identifier: 'free', 'pro', or 'premium'.
     */
    protected function get_current_user_plan() {
        $user_id = get_current_user_id();

        if ( ! $user_id ) {
            return 'free';
        }

        $plan = get_user_meta( $user_id, 'schema_ai_plan', true );

        return $plan ? $plan : 'free';
    }

    /**
     * Return a standardised error response.
     *
     * @param string $code    Machine-readable error code.
     * @param string $message Human-readable message.
     * @param int    $status  HTTP status code.
     * @param array  $data    Optional extra data merged into the error.
     * @return WP_Error
     */
    protected function error_response( $code, $message, $status = 400, $data = array() ) {
        $data['status'] = $status;

        return new WP_Error( $code, $message, $data );
    }

    /**
     * Return a standardised success response.
     *
     * @param mixed $data    Response payload.
     * @param int   $status  HTTP status code.
     * @return WP_REST_Response
     */
    protected function success_response( $data, $status = 200 ) {
        return new WP_REST_Response( $data, $status );
    }
}