Implemented seventh chord practice

ZaneH · Jul 22, 2022 · e71896c · e71896c
1 parent 69a243f
commit e71896c
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Showing 4 changed files with 83 additions and 1 deletion.
diff --git a/src/components/Keyboard/Keyboard.tsx b/src/components/Keyboard/Keyboard.tsx
@@ -7,6 +7,7 @@ import styled, { css } from 'styled-components'
 import {
   getFifthFromMidiNumber,
   getTriadChordFromMidiNumber,
+  getSeventhChordFromMidiNumber,
   MidiDevice,
   midiNumberToNote,
 } from '../../utils'
@@ -126,6 +127,26 @@ const Keyboard = () => {
       // turn the target numbers into target letters to ignore octave for matching
       const targetChordNotes = targetChord.map((n) => midiNumberToNote(n))
 
+      const matches = targetChordNotes.every((e) =>
+        chordStack?.map((cs) => midiNumberToNote(cs)).includes(e)
+      )
+      if (matches) {
+        setNoteTracker?.((nt) => ({
+          ...nt,
+          noteCounter: nt.noteCounter + 1,
+          currentMidiNumber: targetChord[0],
+        }))
+        setChordStack?.([])
+      }
+    } else if (practiceMode === 'seventhChords') {
+      const targetChord = getSeventhChordFromMidiNumber(
+        noteTracker?.nextTargetMidiNumber!,
+        scale!
+      )
+
+      // turn the target numbers into target letters to ignore octave for matching
+      const targetChordNotes = targetChord.map((n) => midiNumberToNote(n))
+
       const matches = targetChordNotes.every((e) =>
         chordStack?.map((cs) => midiNumberToNote(cs)).includes(e)
       )

diff --git a/src/components/Trainer/TrainerPiano.tsx b/src/components/Trainer/TrainerPiano.tsx
@@ -6,6 +6,7 @@ import {
   AVAILABLE_MAJOR_SCALES,
   getFifthFromMidiNumber,
   getTriadChordFromMidiNumber,
+  getSeventhChordFromMidiNumber,
   ignoreOctave,
   OCTAVE_LENGTH,
 } from '../../utils'
@@ -54,6 +55,12 @@ const TrainerPiano = () => {
         } else {
           return getTriadChordFromMidiNumber(nextNote, scale)
         }
+      } else if (practiceMode === 'seventhChords') {
+        if (isHardModeEnabled) {
+          return getSeventhChordFromMidiNumber(noteTracker!.prevNote!, scale)
+        } else {
+          return getSeventhChordFromMidiNumber(nextNote, scale)
+        }
       } else if (practiceMode === 'fifths') {
         if (isHardModeEnabled) {
           return [

diff --git a/src/utils/helpers.ts b/src/utils/helpers.ts
@@ -231,6 +231,52 @@ export const getTriadChordFromMidiNumber = (
   return triadChordMidi
 }
 
+/**
+ * Given a midi number, return four midi numbers that make up a seventh chord with the
+ * provided scale.
+ * @param midiNumber A midi number to start the seventh chord from
+ * @param scale The scale to follow for this chord
+ * @returns 4 midi numbers in an array that make up a seventh chord starting from midiNumber
+ */
+export const getSeventhChordFromMidiNumber = (
+  midiNumber: number,
+  scale: ScaleType
+): number[] => {
+  const scaleKeys = Object.keys(scale.keys)
+  const firstFingerIdx = scaleKeys.indexOf(midiNumber.toString())
+  const firstFinger = Number(scaleKeys[firstFingerIdx])
+  let secondFinger: number
+  let thirdFinger: number
+  let fourthFinger: number
+  const seventhChordMidi: number[] = []
+
+  if (firstFingerIdx < 0) {
+    return seventhChordMidi
+  } else {
+    secondFinger = Number(scaleKeys[(firstFingerIdx + 2) % (SCALE_LENGTH - 1)])
+    const secondFingerIdx = scaleKeys.indexOf(secondFinger.toString())
+    thirdFinger = Number(scaleKeys[(secondFingerIdx + 2) % (SCALE_LENGTH - 1)])
+    const thirdFingerIdx = scaleKeys.indexOf(thirdFinger.toString())
+    fourthFinger = Number(scaleKeys[(thirdFingerIdx + 2) % (SCALE_LENGTH - 1)])
+  }
+
+  if (secondFinger < firstFinger) {
+    secondFinger += OCTAVE_LENGTH
+  }
+
+  if (thirdFinger < secondFinger) {
+    thirdFinger += OCTAVE_LENGTH
+  }
+
+  if (fourthFinger < thirdFinger) {
+    fourthFinger += OCTAVE_LENGTH
+  }
+
+  seventhChordMidi.push(firstFinger, secondFinger, thirdFinger, fourthFinger)
+
+  return seventhChordMidi
+}
+
 /**
  * Returns a random piano note as a string.
  * @returns A random note (ex. C#, Db, F#, Gb)

diff --git a/src/utils/modes/practice.ts b/src/utils/modes/practice.ts
@@ -1,5 +1,9 @@
 export type AvailableScreensType = 'practice' | 'quiz'
-export type AvailablePracticeModesType = 'scales' | 'chords' | 'fifths'
+export type AvailablePracticeModesType =
+  | 'scales'
+  | 'chords'
+  | 'seventhChords'
+  | 'fifths'
 const AVAILABLE_MODES: {
   [key in AvailablePracticeModesType]: { value: string; label: string }
 } = {
@@ -11,6 +15,10 @@ const AVAILABLE_MODES: {
     label: 'Chords',
     value: 'chords',
   },
+  seventhChords: {
+    label: 'Seventh Chords',
+    value: 'seventhChords',
+  },
   fifths: {
     label: 'Fifths',
     value: 'fifths',