import type { Pad } from './types'

export const clamp = (x: number, lo = -1, hi = 1) => Math.max(lo, Math.min(hi, x))

const HOUR = 3_600_000
const MOOD_HALF_LIFE_H = 8

// 高神經質的角色情緒消退較慢：50 為基準，0→0.5 倍，100→1.5 倍
export const halfLife = (neuroticism: number) => MOOD_HALF_LIFE_H * HOUR * (0.5 + neuroticism / 100)

// 讀檔時才計算：x = B + (x − B)·0.5^(Δ/τ)
export function decay(mood: Pad, baseline: Pad, elapsedMs: number, neuroticism: number): Pad {
  if (elapsedMs <= 0) return { p: mood.p, a: mood.a, d: mood.d }
  const k = Math.pow(0.5, elapsedMs / halfLife(neuroticism))
  return {
    p: baseline.p + (mood.p - baseline.p) * k,
    a: baseline.a + (mood.a - baseline.a) * k,
    d: baseline.d + (mood.d - baseline.d) * k,
  }
}

// 單軸每回合變化上限 ±0.3
export const TURN_CAP = 0.3

export function applyDelta(mood: Pad, delta: Pad): Pad {
  const step = (x: number, dx: number) => clamp(x + clamp(dx, -TURN_CAP, TURN_CAP))
  return { p: step(mood.p, delta.p), a: step(mood.a, delta.a), d: step(mood.d, delta.d) }
}

export const MOOD_EVENTS = {
  thanks: { p: 0.15, a: 0.05, d: 0.05 },
  scold: { p: -0.2, a: 0.15, d: -0.1 },
  success: { p: 0.08, a: 0.03, d: 0.05 },
  toolFail: { p: -0.08, a: 0.1, d: -0.08 },
  return: { p: 0.1, a: 0.08, d: 0 },
  lateNight: { p: -0.05, a: -0.1, d: 0 },
  favorite: { p: 0.12, a: 0.08, d: 0.03 },
  ignored: { p: -0.05, a: -0.03, d: -0.03 },
} as const satisfies Record<string, Pad>
export type MoodEvent = keyof typeof MOOD_EVENTS

// 八分區（Mehrabian 的 PAD 八分類）→ 情緒標籤與顏文字
const OCTANTS: Record<string, { label: string; kaomoji: string }> = {
  '+++': { label: '興奮', kaomoji: '(≧▽≦)' },
  '++-': { label: '撒嬌', kaomoji: '(๑>ᴗ<๑)' },
  '+-+': { label: '放鬆', kaomoji: '(´ᴗ`)' },
  '+--': { label: '溫順', kaomoji: '(︶ᴗ︶)' },
  '---': { label: '無聊', kaomoji: '(－_－)' },
  '--+': { label: '不屑', kaomoji: '(￢_￢)' },
  '-++': { label: '生氣', kaomoji: '(╬`益´)' },
  '-+-': { label: '焦慮', kaomoji: '(；´Д`)' },
}
const CALM = { label: '平靜', kaomoji: '(・ω・)' }
const CALM_RADIUS = 0.1

export function moodLabel(m: Pad): { label: string; kaomoji: string } {
  if (Math.abs(m.p) < CALM_RADIUS && Math.abs(m.a) < CALM_RADIUS && Math.abs(m.d) < CALM_RADIUS) return CALM
  const s = (x: number) => (x >= 0 ? '+' : '-')
  return OCTANTS[s(m.p) + s(m.a) + s(m.d)]!
}

const KEYWORDS: [MoodEvent, RegExp][] = [
  ['scold', /笨|白痴|廢物|爛|你很煩|閉嘴|stupid|useless|idiot/i],
  ['thanks', /謝謝|感謝|太棒|好棒|厲害|讚|thanks?|thank you|great job|awesome/i],
  ['success', /成功|完成了|通過|搞定|passed|done|fixed/i],
]

/** 以使用者文字的關鍵字對應心情事件 */
export function keywordEvent(text: string): MoodEvent | null {
  for (const [ev, re] of KEYWORDS) if (re.test(text)) return ev
  return null
}