;; Benchmark: 1.3us
;; Benchmark-Repeat: 1528

; ---------------------------------------------------------
; Object-Oriented Records Example
; ---------------------------------------------------------
; This showcase treats a record as an object by storing
; closures that capture private state.

(do
  ; A factory function (Constructor) for a BankAccount object
  (def make-account (fn [initial-balance]
    (do
      ; 'balance' is a captured parameter, acting as private state
      (def balance initial-balance)

      {
        ; Method: Get current balance
        :balance (fn [] balance)

        ; Method: Deposit money
        :deposit (fn [amount]
          (assign balance (+ balance amount)))

        ; Method: Withdraw money with validation
        :withdraw (fn [amount]
          (if (>= balance amount)
            (assign balance (- balance amount))
            "Insufficient funds"))
      }
    )))

  ; 1. Create an instance
  (def my-acc (make-account 100))

  ; 2. deposit 50 -> balance is now 150
  (def b1 ((.deposit my-acc) 50))

  ; 3. withdraw 20 -> balance is now 130
  (def b2 ((.withdraw my-acc) 20))

  ; 4. withdraw 1000 -> insufficient funds
  (def error-msg ((.withdraw my-acc) 1000))

  ; 5. balance getter
  (def final-balance ((.balance my-acc)))

  (assert-eq 150 b1)
  (assert-eq 130 b2)
  (assert-eq "Insufficient funds" error-msg)
  (assert-eq 130 final-balance)
)