#lang r7rs

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;;                                Constants                                  ;;
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;; All configuration constants for the Pac-Man game. Prevents magic numbers
;; throughout the codebase and makes the game easily configurable.

(define-library (pacman-project constants)
  (import (scheme base))
  (export ;; Window
          window-width-px
          window-height-px

          ;; Maze grid
          cell-size-px
          maze-offset-y
          maze-wall-shrink

          ;; Cell types
          cell-type-coin
          cell-type-wall
          cell-type-empty
          cell-type-key
          cell-type-door

          ;; Coin rendering
          coin-inset

          ;; Sprites
          sprite-scale-pacman
          sprite-scale-key
          sprite-scale-key-ui

          ;; Animation
          animation-interval-ms

          ;; Score
          points-per-coin

          ;; Time limit
          start-time-seconds
          ms-per-second
          time-bonus-per-coin

          ;; Key placement
          max-placement-attempts

          ;; Rotation angles
          rotation-right
          rotation-left
          rotation-up
          rotation-down

          ;; UI positions
          score-text-size
          score-text-x
          score-text-y
          time-text-size
          time-label-x
          time-label-y
          time-value-x
          time-value-y
          separator-x
          separator-width
          key-ui-x
          key-ui-y)

  (begin

    ;; Window dimensions
    (define window-width-px 1000)
    (define window-height-px 830)

    ;; Maze grid configuration
    (define cell-size-px 24)
    (define maze-offset-y 97)
    (define maze-wall-shrink 6)

    ;; Cell type encoding for the maze grid
    (define cell-type-coin 0)
    (define cell-type-wall 1)
    (define cell-type-empty 2)
    (define cell-type-key 3)
    (define cell-type-door 4)

    ;; Coin rendering: inset in pixels from cell edge
    (define coin-inset 7)

    ;; Sprite scale factors
    (define sprite-scale-pacman 1.5)
    (define sprite-scale-key 1.5)
    (define sprite-scale-key-ui 3)

    ;; Animation timing
    (define animation-interval-ms 100)

    ;; Score configuration
    (define points-per-coin 10)

    ;; Time limit configuration
    (define start-time-seconds 60)
    (define ms-per-second 1000)
    (define time-bonus-per-coin 1)

    ;; Key placement
    (define max-placement-attempts 1000)

    ;; Rotation angles (degrees)
    (define rotation-right 0)
    (define rotation-left 180)
    (define rotation-up 90)
    (define rotation-down -90)

    ;; UI positions for score display
    (define score-text-size 40)
    (define score-text-x 560)
    (define score-text-y 20)

    ;; UI positions for time display (right side of separator)
    (define time-text-size 35)
    (define time-label-x 710)
    (define time-label-y 300)
    (define time-value-x 800)
    (define time-value-y 400)

    ;; Separator line between play field and UI
    (define separator-x 670)
    (define separator-width 24)

    ;; Key UI position (next to score)
    (define key-ui-x 20)
    (define key-ui-y 35)))