feat: morse data library with validation and challenge selection

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

client/src/lib/morse.test.ts

@@ -0,0 +1,110 @@
+import { describe, it, expect } from 'vitest'
+import {
+  MORSE,
+  NOVICE_LETTERS,
+  OPERATOR_WORDS,
+  wpmToTiming,
+  validatePhrase,
+  pickChallenge,
+} from './morse'
+
+describe('MORSE map', () => {
+  it('has all 26 letters', () => {
+    const letters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'.split('')
+    letters.forEach(l => expect(MORSE[l]).toBeDefined())
+  })
+  it('A is .-', () => expect(MORSE['A']).toBe('.-'))
+  it('S is ...', () => expect(MORSE['S']).toBe('...'))
+  it('O is ---', () => expect(MORSE['O']).toBe('---'))
+})
+
+describe('NOVICE_LETTERS', () => {
+  it('has 12 letters', () => expect(NOVICE_LETTERS).toHaveLength(12))
+  it('includes A E T I N S H R D L U O', () => {
+    ;['A','E','T','I','N','S','H','R','D','L','U','O'].forEach(l =>
+      expect(NOVICE_LETTERS).toContain(l)
+    )
+  })
+})
+
+describe('OPERATOR_WORDS', () => {
+  it('has at least 20 words', () => expect(OPERATOR_WORDS.length).toBeGreaterThanOrEqual(20))
+  it('all words use only Novice letters', () => {
+    const novice = new Set(['A','E','T','I','N','S','H','R','D','L','U','O'])
+    OPERATOR_WORDS.forEach(word => {
+      word.split('').forEach(l => expect(novice.has(l)).toBe(true))
+    })
+  })
+})
+
+describe('wpmToTiming', () => {
+  it('10 WPM gives dot=120ms', () => {
+    expect(wpmToTiming(10).dot).toBe(120)
+  })
+  it('dash is 3x dot', () => {
+    const t = wpmToTiming(10)
+    expect(t.dash).toBe(t.dot * 3)
+  })
+  it('20 WPM gives dot=60ms', () => {
+    expect(wpmToTiming(20).dot).toBe(60)
+  })
+})
+
+describe('validatePhrase', () => {
+  it('accepts valid phrase for E (.)', () => {
+    expect(validatePhrase('go', 'E')).toEqual({ valid: true })
+  })
+  it('accepts valid phrase for A (.-)', () => {
+    expect(validatePhrase('go WALKING', 'A')).toEqual({ valid: true })
+  })
+  it('accepts valid phrase for S (...)', () => {
+    expect(validatePhrase('go go go', 'S')).toEqual({ valid: true })
+  })
+  it('rejects wrong word count', () => {
+    const r = validatePhrase('go go', 'S')
+    expect(r.valid).toBe(false)
+    expect(r.message).toContain('3')
+  })
+  it('rejects long word for dot position', () => {
+    const r = validatePhrase('WALKING go go', 'S')
+    expect(r.valid).toBe(false)
+  })
+  it('rejects short word for dash position', () => {
+    const r = validatePhrase('go go', 'A')
+    expect(r.valid).toBe(false)
+  })
+  it('rejects unknown letter', () => {
+    expect(validatePhrase('test', '1')).toEqual({ valid: false, message: 'Unknown letter' })
+  })
+  it('handles empty phrase', () => {
+    expect(validatePhrase('', 'E')).toEqual({ valid: false, message: expect.stringContaining('1') })
+  })
+})
+
+describe('pickChallenge', () => {
+  it('always returns item from pool', () => {
+    const pool = ['A', 'E', 'T', 'I']
+    const result = pickChallenge(pool, {}, [])
+    expect(pool).toContain(result)
+  })
+  it('avoids last 3 items when pool is large enough', () => {
+    const pool = ['A', 'E', 'T', 'I', 'N', 'S']
+    const history = ['A', 'E', 'T']
+    for (let i = 0; i < 20; i++) {
+      const result = pickChallenge(pool, {}, history)
+      expect(['A','E','T']).not.toContain(result)
+    }
+  })
+  it('prefers items with lower accuracy', () => {
+    const pool = ['A', 'B']
+    const stats = {
+      A: { correct: 9, attempts: 10 },
+      B: { correct: 1, attempts: 10 },
+    }
+    let bCount = 0
+    for (let i = 0; i < 100; i++) {
+      if (pickChallenge(pool, stats, []) === 'B') bCount++
+    }
+    expect(bCount).toBeGreaterThan(60)
+  })
+})