Test transaction - MB Custom Table

<?php
// Step 1: Register a model.
add_action( 'init', 'prefix_register_transaction_model' );
function prefix_register_transaction_model() {
    mb_register_model( 'transaction', [
        'table'  => 'transactions',
        'labels' => [
            'name'          => 'Transactions',
            'singular_name' => 'Transaction',
        ],
        'menu_icon' => 'dashicons-money-alt',
    ] );
}

// Step 2: Create a custom table for the model.
add_action( 'init', 'prefix_register_transaction_table' );
function prefix_register_transaction_table() {
    MetaBox\CustomTable\API::create(
        'transactions',                    // Table name.
        [                                  // Table columns (without ID).
            'created_at' => 'DATETIME',
            'amount'     => 'BIGINT',
            'email'      => 'VARCHAR(20)',
            'gateway'    => 'TEXT',
            'status'     => 'VARCHAR(20)',
            'screenshot' => 'TEXT',
        ],
        ['email', 'status'],               // List of index keys.
        true                               // THIS: Must be true for models.
    );
}

// Step 3: Register fields for model, corresponding to the custom table structure.
add_filter( 'rwmb_meta_boxes', 'prefix_register_transaction_fields' );
function prefix_register_transaction_fields( $meta_boxes ) {
    $meta_boxes[] = [
        'title'        => 'Transaction Details',
        'models'       => ['transaction'], // Model name
        'storage_type' => 'custom_table',  // Must be 'custom_table'
        'table'        => 'transactions',  // Custom table name
        'fields'       => [
            [
                'id'          => 'created_at',
                'type'        => 'datetime',
                'name'        => 'Created at',
                'js_options'  => [
                    'timeFormat' => 'HH:mm:ss',
                ],
                'admin_columns' => true,
            ],
            [
                'id'     => 'amount',
                'type'   => 'number',
                'name'   => 'Amount',
                'append' => 'USD',
                'admin_columns' => [
                    'position' => 'after id',
                    'sort'     => true,
                ],
            ],
            [
                'id'   => 'gateway',
                'name' => 'Gateway',
                'admin_columns' => true,
            ],
            [
                'id'   => 'status',
                'type' => 'select',
                'name' => 'Status',
                'options' => [
                    'pending'   => 'Pending',
                    'completed' => 'Completed',
                    'refunded'  => 'Refunded',
                ],
                'admin_columns' => true,
            ],
        ],
    ];

    $meta_boxes[] = [
        'title'        => 'Additional Transaction Details',
        'models'       => ['transaction'], // Model name
        'storage_type' => 'custom_table',  // Must be 'custom_table'
        'table'        => 'transactions',  // Custom table name
        'fields'       => [
            [
                'id'   => 'email',
                'type' => 'email',
                'name' => 'Email',
                'admin_columns' => [
                    'position'   => 'after amount',
                    'searchable' => true,
                ],
            ],
            [
                'id'            => 'screenshot',
                'type'          => 'image_advanced',
                'name'          => 'Screenshots',
                'admin_columns' => true,
            ],
        ],
    ];

    return $meta_boxes;
}

add_action( 'init', function() {
    // Get raw value via API.
    $value = \MetaBox\CustomTable\API::get_value( 'screenshot', 17, 'transactions' );
    // ray( $value );

    // Get meaningful value with helper function.
    $value2 = rwmb_meta( 'screenshot', [
        'object_type' => 'model',
        'type'        => 'transaction',
    ], 17 );
    // ray( $value2 );
}, 30 ); // Priority 30 to ensure meta boxes are registered (at init with priority = 20)