#lang racket/base

(require racket/class
         "../library-cfg.rkt"
         "../../misc/utils.rkt")

(provide media-library%)

(define media-library%
  (class object%
    (init-field
     cfg)

    (check/c media-library%
             cfg
             (is-a?/c library-cfg%))

    (define cfg-revision
      -1)

    (define root-container
      #f)

    (define/private (reset-if-needed!)
      (let ((current-revision (send cfg get-revision)))
        (unless (= cfg-revision current-revision)
          (set! cfg-revision current-revision)
          (set! root-container #f))))

    (define/public (get-cfg)
      cfg)

    (define/public (get-id)
      (send cfg get-id))

    (define/public (get-kind)
      (send cfg get-kind))

    (define/public (get-kind-version)
      (send cfg get-kind-version))

    (define/public (get-root-container)
      (reset-if-needed!)
      (when (eq? root-container #f)
        (set! root-container
              (send this make-root-container)))
      root-container)

    (abstract make-root-container)

    (super-new)))