Implement SonicWeave Interchange exporter

ref #34

src/components/ExporterButtons.vue

@@ -125,6 +125,12 @@ function doExport(exporter: ExporterKey) {
       date: new Date()
     }
 
+    if (exporter === 'xendevs') {
+      const { rawIntervals, unisonFrequency } = scale.computeRawScale()
+      params.rawIntervals = rawIntervals
+      params.unisonFrequency = unisonFrequency
+    }
+
     exportFile(exporter, params)
   })
 }
@@ -260,6 +266,10 @@ function doExport(exporter: ExporterKey) {
     <p><strong>MTS Sysex Bulk Tuning Dump (.syx)</strong></p>
     <p>Binary data of a Bulk Tuning Dump SysEx message</p>
   </a>
+  <a href="#" class="btn" @click="doExport('xendevs')">
+    <p><strong>SonicWeave Interchange (.swi)</strong></p>
+    <p>Simplified Scale Workshop 3 format</p>
+  </a>
   <h3>Documentation</h3>
   <p>
     You can read about the new SonicWeave syntax

src/exporters/__tests__/test-data.ts

@@ -4,7 +4,8 @@ import { UNIX_NEWLINE, WINDOWS_NEWLINE } from '../../constants'
 import { Scale } from '../../scale'
 import { Fraction } from 'xen-dev-utils'
 
-export function getTestData(appTitle: string) {
+export function getTestData(appTitle: string, raw = false) {
+  const sourceText = '100.\nC5_5\n4\\5\n5/3\n1,3591409142295225r\n3486784401/3276800000\n2/1'
   const absoluteC5 = new Interval(TimeMonzo.fromFractionalFrequency(528, 3), 'logarithmic', 0, {
     type: 'AbsoluteFJS',
     pitch: {
@@ -19,7 +20,16 @@ export function getTestData(appTitle: string) {
     subscripts: [[5, '']]
   })
   const visitor = getSourceVisitor()
+  // Prefix
   visitor.visit(parseAST('A4 = 440 Hz').body[0])
+  let rawIntervals: Interval[] | undefined
+  let unisonFrequency: TimeMonzo | undefined
+  if (raw) {
+    // Body
+    visitor.executeProgram(parseAST(sourceText))
+    rawIntervals = visitor.currentScale
+    unisonFrequency = visitor.rootContext!.unisonFrequency
+  }
   const ev = visitor.createExpressionVisitor()
   const relativeC5 = relative.bind(ev)(absoluteC5)
 
@@ -80,9 +90,11 @@ export function getTestData(appTitle: string) {
     appTitle,
     description: 'A scale for testing if the exporter works',
     midiOctaveOffset: 0,
-    sourceText: '100.\nC5_5\n4\\5\n5/3\n1,3591409142295225r\n3486784401/3276800000\n2/1',
+    sourceText,
     labels: ['100.', 'C5_5', '4\\5', '5/3', '1,3591409142295225r', '3486784401/3276800000', '2/1'],
-    date: new Date('2022-02-22T20:22Z')
+    date: new Date('2022-02-22T20:22Z'),
+    rawIntervals,
+    unisonFrequency
   }
   return params
 }

src/exporters/__tests__/xen-devs.spec.ts

@@ -0,0 +1,23 @@
+import { describe, it, expect } from 'vitest'
+
+import SonicWeaveInterchangeExporter from '../xen-devs'
+
+import { getTestData } from './test-data'
+
+describe('SonicWeave Interchange exporter', () => {
+  it('can handle all line types', () => {
+    const params = getTestData('SWI exporter unit test v0.0.0')
+    const exporter = new SonicWeaveInterchangeExporter(params)
+    expect(exporter.getFileContents()).toBe(`(* Created using SWI exporter unit test v0.0.0 *)
+
+"Test Scale"
+[1/12> "" niente
+[1 1 -1> "" niente
+[4/5> "" niente
+[0 -1 1> "" niente
+[531.234049066756>@rc "" niente
+[-20 20 -5> "" niente
+[1> "" niente
+`)
+  })
+})

src/exporters/base.ts

@@ -1,5 +1,5 @@
 import type { Scale } from '@/scale'
-import type { Interval } from 'sonic-weave'
+import type { Interval, TimeMonzo } from 'sonic-weave'
 
 export type LineFormat = 'label' | 'cents' | 'frequency' | 'decimal' | 'degree'
 
@@ -23,6 +23,8 @@ export type ExporterParams = {
   integratePeriod?: boolean
   presetIndex?: number
   centsFractionDigits?: number
+  rawIntervals?: Interval[]
+  unisonFrequency?: TimeMonzo
 }
 
 export class BaseExporter {

src/exporters/index.ts

@@ -8,6 +8,7 @@ import PureDataExporter from '@/exporters/pure-data'
 import SoniccoutureExporter from '@/exporters/soniccouture'
 import AbletonAsclExporter from '@/exporters/ableton'
 import MaxMSPExporter from '@/exporters/max-msp'
+import SonicWeaveInterchangeExporter from './xen-devs'
 
 const EXPORTERS = {
   scalascl: ScalaSclExporter,
@@ -21,7 +22,8 @@ const EXPORTERS = {
   ableton: AbletonAsclExporter,
   puredata: PureDataExporter,
   soniccouture: SoniccoutureExporter,
-  maxmsp: MaxMSPExporter
+  maxmsp: MaxMSPExporter,
+  xendevs: SonicWeaveInterchangeExporter
 }
 
 export type ExporterKey = keyof typeof EXPORTERS

src/exporters/xen-devs.ts

@@ -0,0 +1,37 @@
+import { APP_TITLE } from '@/constants'
+import { BaseExporter, type ExporterParams } from '@/exporters/base'
+import { literalToString } from 'sonic-weave'
+
+// Specs: https://github.com/xenharmonic-devs/sonic-weave/blob/main/documentation/interchange.md
+export default class SonicWeaveInterchangeExporter extends BaseExporter {
+  constructor(params: ExporterParams) {
+    super(params)
+  }
+
+  getFileContents() {
+    const params = this.params
+    const lines = [`(* Created using ${params.appTitle ?? APP_TITLE} *)`, '']
+    lines.push(JSON.stringify(params.scale.title))
+    if (params.unisonFrequency) {
+      const unisonFrequency = literalToString(params.unisonFrequency.asInterchangeLiteral())
+      lines.push(`1 = ${unisonFrequency}`)
+      lines.push('')
+    }
+    const intervals = params.rawIntervals ?? params.relativeIntervals
+    for (const interval of intervals) {
+      const universal = interval.shallowClone()
+      universal.node = universal.asMonzoLiteral(true)
+      let line = universal.toString(undefined, true)
+      if (line.startsWith('(') && line.endsWith(')')) {
+        line = line.slice(1, -1)
+      }
+      lines.push(line)
+    }
+    lines.push('')
+    return lines.join('\n')
+  }
+
+  saveFile() {
+    super.saveFile(this.params.filename + '.swi', this.getFileContents())
+  }
+}

src/stores/scale.ts

@@ -692,6 +692,19 @@ export const useScaleStore = defineStore('scale', () => {
 
   const history = undoHistory(serialize, restore)
 
+  // Only one exporter makes use of this so we don't maintain it in active memory.
+  function computeRawScale() {
+    const globalVisitor = getGlobalScaleWorkshopVisitor()
+    const visitor = new StatementVisitor(globalVisitor)
+    visitor.isUserRoot = true
+    const ast = parseAST(sourceText.value)
+    visitor.executeProgram(ast)
+    return {
+      rawIntervals: visitor.currentScale,
+      unisonFrequency: visitor.rootContext!.unisonFrequency
+    }
+  }
+
   return {
     // Live state
     ...LIVE_STATE,
@@ -728,6 +741,7 @@ export const useScaleStore = defineStore('scale', () => {
     labelForIndex,
     toJSON,
     fromJSON,
+    computeRawScale,
     // Mini-stores
     history
   }