// ═══════════════════════════════════════════════════════════════
// Gameplay constants — all tunable magic numbers in one place
// ═══════════════════════════════════════════════════════════════

// --- Performance mode ---
const PERF_KEY = 'bf_perf_mode'

function detectLowEnd(): boolean {
  if (typeof navigator === 'undefined') return false
  const cores = navigator.hardwareConcurrency || 4
  const mobile = navigator.maxTouchPoints > 0
  return cores < 4 || mobile
}

function loadPerfPref(): boolean | null {
  try {
    const v = localStorage.getItem(PERF_KEY)
    if (v === '1') return true
    if (v === '0') return false
  } catch {}
  return null
}

let _perfMode = loadPerfPref() ?? detectLowEnd()

export function isPerfMode(): boolean { return _perfMode }
export function setPerfMode(on: boolean): void {
  _perfMode = on
  try { localStorage.setItem(PERF_KEY, on ? '1' : '0') } catch {}
}

/** Scale a particle count down in performance mode (40%) or reduced motion (20%) */
export function perfParticles(count: number): number {
  if (_reducedMotion) return Math.max(1, Math.round(count * 0.2))
  return _perfMode ? Math.max(1, Math.round(count * 0.4)) : count
}

// --- Reduced motion ---
const _reducedMotion = typeof window !== 'undefined'
  ? window.matchMedia('(prefers-reduced-motion: reduce)').matches
  : false

export function isReducedMotion(): boolean { return _reducedMotion }

// --- Haptic feedback ---
export function haptic(ms: number = 50): void {
  try { navigator?.vibrate?.(ms) } catch { /* no vibration support */ }
}

// --- Choreography selection probabilities ---
export const CREATOR_ULTIMATE_CHANCE = 0.5          // Creator ultimate chance (non-crit); 1.0 on crits
export const CREATOR_THEMED_MOVE_RATIO = 0.6        // Creator uses creator-themed moves 60% of the time
export const CRIT_THEMED_RATIO = 0.5                // On crits: 50% themed, 50% epic generic
export const CHOREOGRAPHY_THEMED_RATIO = 0.6        // Normal: 60% themed
export const CHOREOGRAPHY_GENERIC_CUTOFF = 0.85     // Normal: 25% generic (0.60–0.85), 15% wild (0.85–1.0)

// --- Tier-gated ultimate chances ---
export const TIER_ULTIMATE_CHANCES: Record<number, number> = {
  2: 0.15,
  3: 0.20,
  4: 0.30,
  5: 0.40,
}

// --- Morph system ---
export const CREATOR_MORPH_CRIT_CHANCE = 0.7        // Creator morphs on devastating crits 70%
export const CREATOR_MORPH_INTENSITY_THRESHOLD = 0.6 // Creator morphs when intensity > 0.6
export const BOT_MORPH_CRIT_CHANCE = 0.4            // Regular bots morph on devastating crits 40%
export const BOT_MORPH_INTENSITY_THRESHOLD = 0.7    // Regular bots morph when intensity > 0.7

// --- Creator cameo ---
export const CREATOR_CAMEO_CHANCE = 0.06            // 6% per round in non-creator fights

// --- Round exchange probabilities ---
export const DODGE_CHANCE = 0.12                    // Defender dodges instead of being hit
export const COUNTER_ATTACK_CHANCE = 0.25           // Defender counters after getting hit
export const SCANLINE_GLITCH_CHANCE = 0.25          // Random scanline glitch during exchanges
export const COMEDY_SFX_CHANCE = 0.15               // Comedy sound on non-decisive hits
export const PHYSICAL_CONTACT_BASE = 0.35           // Base chance for brawl/clinch
export const PHYSICAL_CONTACT_INTENSITY_SCALE = 0.2 // Added per unit of intensity
export const PHYSICAL_CONTACT_EXCHANGE_BONUS = 0.15 // Added after first exchange
export const CROWD_REACTION_CHANCE = 0.4            // Crowd reacts to round results
export const MAYBE_SHOW_HUMAN_CHANCE = 0.2          // Show human coach
export const CREATOR_VOICE_LINE_CHANCE = 0.6        // Creator gets a voice line

// --- Hyperdetail (grotesque close-up) ---
export const HYPERDETAIL_BASE_CHANCE = 0.05         // Base hyperdetail chance
export const HYPERDETAIL_INTENSITY_SCALE = 0.45     // Scales with intensity