/**
 * settings.js
 * Static game constants — all tunable values live here.
 * Do not import game state; this file has zero side-effects.
 */
const SETTINGS = Object.freeze({

  /* ── Canvas ───────────────────────────────────────────────── */
  CANVAS_WIDTH:  900,
  CANVAS_HEIGHT: 520,
  HEADER_HEIGHT: 60,

  /* ── Timing ───────────────────────────────────────────────── */
  GAME_DURATION:        180,    // seconds
  PLAYER_MOVE_COOLDOWN: 180,    // ms between tile moves
  LAB_ANALYZE_TIME:    3000,    // ms to analyze a special good
  GOOD_WAIT_TIME:      2500,    // ms a good waits at belt end before dropping
  MED_WAIT_TIME:       3500,    // ms medication waits at pickup point

  /* ── Scoring ──────────────────────────────────────────────── */
  POINTS_GOOD_LAB:       1,
  POINTS_SPECIAL_PATIENT: 5,
  POINTS_DROP_GOOD:      -1,
  POINTS_DROP_SPECIAL:   -3,

  /* ── Carry limit ──────────────────────────────────────────── */
  MAX_CARRY: 5,

  /* ── Special good probability (1 in 7) ───────────────────── */
  SPECIAL_GOOD_CHANCE: 1 / 7,

  /* ── Layout — zone x boundaries ──────────────────────────── */
  LEFT_ZONE_START:   0,
  LEFT_ZONE_END:     350,
  MIDDLE_ZONE_START: 350,
  MIDDLE_ZONE_END:   600,
  RIGHT_ZONE_START:  600,
  RIGHT_ZONE_END:    900,

  /* ── Vertical rows (y centres, shared across all zones) ───── */
  //   Row 0 = top, Row 1 = middle, Row 2 = bottom
  BELT_ROWS: [155, 300, 445],

  /* ── Player grid (4 cols × 3 rows inside middle zone) ──────── */
  PLAYER_COLS:      3,
  PLAYER_ROWS:      3,
  PLAYER_COL_WIDTH: 100,  // px between column centres
  PLAYER_SIZE:      36,   // bounding box size for drawing
  BELT_HEIGHT:      13,   // visual belt strip height (px)

  /* ── Belt speeds ──────────────────────────────────────────── */
  LEFT_BELT_SPEED:  45,   // px / sec  (goods move → right)
  RIGHT_BELT_SPEED: 33,   // px / sec  (medication moves ← left)

  /* ── Left belt spawn intervals (ms) ──────────────────────── */
  BELT_MIN_SPAWN: 3200,
  BELT_MAX_SPAWN: 6500,

  /* ── Staggered initial spawn offsets per belt (ms) ─────────── */
  BELT_INIT_OFFSETS: [600, 2400, 4200],

  /* ── Item sizes ───────────────────────────────────────────── */
  GOOD_SIZE: 26,

  /* ── Patient happy flash duration ────────────────────────── */
  PATIENT_HAPPY_DURATION: 1800,   // ms

  /* ── Colours ──────────────────────────────────────────────── */
  COLOR_BG:           '#0a1628',
  COLOR_HEADER:       '#0d1e38',
  COLOR_HEADER_LINE:  '#1a4070',
  COLOR_BELT:         '#152840',
  COLOR_BELT_STRIPE:  '#1e3d5c',
  COLOR_BELT_EDGE:    '#2a5a80',
  COLOR_BELT_R:       '#14283c',
  COLOR_BELT_STRIPE_R:'#1c3650',
  COLOR_GOOD:         '#f0a030',
  COLOR_GOOD_OUTLINE: '#c07010',
  COLOR_SPECIAL:      '#ff44aa',
  COLOR_SPECIAL_OUT:  '#cc1177',
  COLOR_MED:          '#44ffaa',
  COLOR_MED_OUT:      '#11cc77',
  COLOR_PLAYER:       '#4499ff',
  COLOR_PLAYER_DARK:  '#2266cc',
  COLOR_PLAYER_CARRY: '#88ccff',
  COLOR_LAB:          '#1a4830',
  COLOR_LAB_LIGHT:    '#22aa55',
  COLOR_LAB_OUTLINE:  '#33dd77',
  COLOR_PATIENT:      '#ff8844',
  COLOR_PATIENT_DARK: '#cc5511',
  COLOR_PATIENT_HAPPY:'#ffdd44',
  COLOR_TEXT:         '#88ccff',
  COLOR_SCORE_VAL:    '#ffdd44',
  COLOR_TIMER_OK:     '#44dd88',
  COLOR_TIMER_WARN:   '#ffaa22',
  COLOR_TIMER_DANGER: '#ff4444',
  COLOR_ZONE_DIV:     '#1a3a5c',
  COLOR_ZONE_DIV2:    '#0f2a40',
  COLOR_SHADOW:       'rgba(0,0,0,0.45)',

});