+
+/* State */
+const output = {
+ print: (string) => {},
+ updateViews: () => {}
+}
+let wasmMem, wasmMain
+
+/* Environment functions */
+const bufString = (arrayBuf, addr, u) =>
+ String.fromCharCode.apply(null, new Uint16Array(arrayBuf, addr, u >> 1))
+const wasmString = (addr, u) => bufString(wasmMem, addr, u)
+const wasmBase = () => new DataView(wasmMem, 14348, 4).getUint32(0,true)
+const strToArrayBuffer = (str) => {
+ const buf = new ArrayBuffer(str.length << 1)
+ const bufView = new Uint16Array(buf)
+ for (let i = 0, strLen = str.length; i < strLen; i++)
+ bufView[i] = str.charCodeAt(i)
+ return buf
+}
+const bufJoin = (buf1, buf2) => {
+ const newBuf = new Uint8Array(buf1.byteLength + buf2.byteLength)
+ newBuf.set(new Uint8Array(buf1), 0)
+ newBuf.set(new Uint8Array(buf2), buf1.byteLength)
+ return newBuf.buffer
+}
+
+/* I/O Channel Drivers */
+const channels = []
+const getChannel = (chno) => {
+ const channel = channels[chno]
+ if (!channel)
+ throw new Error(`invalid channel access ${chno}`)
+ return channel
+}
+class Channel {
+ constructor(opt) {
+ opt = opt || Object.create(null)
+ opt.chno = channels.indexOf(undefined)
+ if (opt.chno === -1)
+ opt.chno = channels.length
+ Object.assign(this, opt)
+ if (this.buffer === undefined)
+ this.buffer = new ArrayBuffer(0)
+ channels[this.chno] = this
+ return this
+ }
+ read(writeArray, writeAddr, writeMax) {
+ const bufBytes = Math.min(writeMax, this.buffer.byteLength)
+ new Uint8Array(writeArray).set(new Uint8Array(this.buffer, 0, bufBytes), writeAddr)
+ this.buffer = this.buffer.slice(bufBytes)
+ return bufBytes
+ }
+ write(readArray, readAddr, readSize) {
+ this.buffer = bufJoin(this.buffer, new Uint8Array(readArray, readAddr, readSize))
+ wasmMain(this.chno)
+ output.updateViews()
+ }
+ send(readArray, readAddr, readSize) {
+ this.write(readArray, readAddr, readSize)
+ }
+}
+
+/* System runtime */
+const simstack = []
+const rstack = []
+const dictionary = { EXECUTE: 12 }
+const doesDictionary = {}
+const wasmImport = {
+ env: {
+ pop: () => simstack.pop(),
+ push: (val) => simstack.push(val),
+ rinit: () => rstack.length = 0,
+ rpop: () => rstack.pop(),
+ rpush: (val) => rstack.push(val),
+ sys_write: (chno, addr, u) => getChannel(chno).write(wasmMem, addr, u),
+ sys_read: (chno, addr, u) => getChannel(chno).read(wasmMem, addr, u),
+ sys_send: (chno, addr, u) => getChannel(chno).send(wasmMem, addr, u),
+ sys_connect: (addr, u) => {
+ //TODO: call into the module to wasm fn "event" to push an event
+ //to forth, which pushes esi to the return stack and queues the
+ //callback function provided from listen. reqaddr could be
+ //"fetch", in which case no channel is used. otherwise very
+ //similar to sys_fetch.
+
+ //callbacks are events, like listen events
+ //totally event-driven, one listener per event
+ //other listen types: mouse, keyboard, touch, main_loop (10ms interval), wrtc, etc
+ //fetch is different because it offers no "write" interface, doesn't repeat
+ },
+ sys_fetch: (chno, addr, u) => {
+ const str = wasmString(addr, u)
+ console.log(`fetching: ${str} || ${addr} ${u}`)
+ const args = JSON.parse(wasmString(addr, u))
+ console.log(args)
+ const url = args.url
+ delete args.url
+ const channel = channels[chno]
+ if (!channel) {
+ console.error(`invalid channel fetch: ${chno}`)
+ return -1
+ }
+ fetch(url, args).then((re) => {
+ if (args.headers === undefined ||
+ args.headers['content-type'] === undefined ||
+ args.headers['content-type'].toLowerCase().indexOf('text/plain') === 0 )
+ re.text().then((txt) => channel.write(strToArrayBuffer(txt), 0, txt.length << 1))
+ else {
+ const reader = new FileReader()
+ reader.onload = (evt) => channel.write(evt.target.result, 0, evt.target.result.byteLength)
+ re.blob().then((blob) => reader.readAsArrayBuffer(blob))
+ }
+ }).catch(console.error)
+ return 0
+ },
+ sys_open: () => new Channel().chno,
+ sys_close: (chno) => chno < 3 ? 0 : delete channels[chno],
+ sys_echo: (val) => output.print(`\\\ => ${val.toString(wasmBase())}\n`),
+ sys_log: (addr, u) => console.log(`=> ${wasmString(addr, u)}`),
+ sys_reflect: (addr) => {
+ console.log(`reflect: ${addr}: ${
+ new DataView(wasmMem, addr, 4)
+ .getUint32(0,true)
+ }`)
+ },
+ vocab_get: (addr, u) => dictionary[wasmString(addr, u).toUpperCase()] || 0,
+ vocab_set: (addr, u, v) => dictionary[wasmString(addr, u).toUpperCase()] = v,
+ does_get: (addr, u) => doesDictionary[wasmString(addr, u).toUpperCase()] || 0,
+ does_set: (addr, u, v) => doesDictionary[wasmString(addr, u).toUpperCase()] = v,
+ is_whitespace: (key) => /\s/.test(String.fromCharCode(key)),
+ sys_stack: () => { console.log(`[${simstack}][${rstack}]`)
+ console.log(new Uint32Array(wasmMem, 16900, 28))
+ },
+ sys_parsenum: (addr, u) => {
+ const answer = Number.parseInt(wasmString(addr, u), wasmBase())
+ if (Number.isNaN(answer))
+ return -1
+ new DataView(wasmMem, addr, 4).setUint32(0,answer,true)
+ return 0
+ },
+ sys_words: () => {
+ output.print(Object.getOwnPropertyNames(dictionary).toString().split(',').join(' '))
+ }
+ }
+}
+
+/* Initialization */
+/* 0 STDIN, 1 STDOUT, 2 STDERR */
+new Channel({
+ send(readArray, readAddr, readSize) { output.print(bufString(readArray, readAddr, readSize)) }
+})
+new Channel({
+ write(readArray, readAddr, readSize) { output.print(bufString(readArray, readAddr, readSize)) },
+ send(readArray, readAddr, readSize) { output.print(`\n\\\ => ${bufString(readArray, readAddr, readSize)}\n`) }
+})
+new Channel({
+ write(readArray, readAddr, readSize) { console.error(bufString(readArray, readAddr, readSize)) }
+})
+
+/* Fetch wasm file, and initial forth file */
+Promise.all([