Add currency conversion support to Math blocks

electron/config.js

@@ -27,6 +27,14 @@ const schema = {
     },
 
     theme: {type: "string", default: "system"},
+
+    currency: {
+        type: "object",
+        properties: {
+            data: {type: "object"},
+            timeFetched: {type: "number"},
+        },
+    },
 }
 
 const defaults = {

electron/main/cors.ts

@@ -0,0 +1,33 @@
+import { BrowserWindow } from 'electron'
+
+export function fixElectronCors(win: BrowserWindow) {
+    win.webContents.session.webRequest.onBeforeSendHeaders(
+        (details, callback) => {
+            callback({ requestHeaders: { Origin: '*', ...details.requestHeaders } });
+        },
+    );
+
+    win.webContents.session.webRequest.onHeadersReceived((details, callback) => {
+        // check if Access-Control-Allow-Origin header is set to ["*"], and if not, set it to that
+        let newHeaders = details.responseHeaders
+        let headerAlreadySet = false
+
+        for (const [key, value] of Object.entries(details.responseHeaders)) {
+            if (key.toLowerCase() === "access-control-allow-origin") {
+                if (value[0] === "*") {
+                    headerAlreadySet = true
+                }
+                break
+            }
+        }
+        if (!headerAlreadySet) {
+            newHeaders = {
+                "access-control-allow-origin": ["*"],
+                ...details.responseHeaders,
+            }
+        }
+        callback({
+            responseHeaders: newHeaders,
+        });
+    });
+}

electron/main/index.ts

@@ -10,6 +10,7 @@ import CONFIG from "../config"
 import { onBeforeInputEvent } from "../keymap"
 import { isMac } from '../detect-platform';
 import { initializeAutoUpdate } from './auto-update';
+import { fixElectronCors } from './cors';
 
 
 // The built directory structure
@@ -137,6 +138,8 @@ async function createWindow() {
         }
         return { action: 'deny' }
     })
+
+    fixElectronCors(win)
 }
 
 app.whenReady().then(createWindow).then(async () => {

electron/preload/currency.ts

@@ -0,0 +1,37 @@
+import CONFIG from "../config"
+
+const STALE_TIME = 1000 * 3600 * 24
+
+export default async function getCurrencyData() {
+    const currency = CONFIG.get("currency")
+    if (currency?.timeFetched && (new Date()).getTime() - currency.timeFetched < STALE_TIME) {
+        // we already have currency data and it's not stale
+        return currency.data
+    } else {
+        // we either don't have currency data, or it's stale
+        let response
+        try {
+            response = await fetch("https://currencies.heynote.com/rates.json", {cache: "no-cache"})
+        } catch(err) {
+            // if we got an error, but have stale currency data, we'll use that
+            if (currency?.data) {
+                return currency.data
+            }
+        }
+
+        if (response.ok) {
+            const data = JSON.parse(await response.text())
+            CONFIG.set("currency", {
+                data,
+                timeFetched: (new Date()).getTime(),
+            })
+            return data
+        } else {
+            // if we got an error, but have stale currency data, we'll use that
+            console.log("Error retrieving currency data:", response)
+            if (currency?.data) {
+                return currency.data
+            }
+        }
+    }
+}

electron/preload/index.ts

@@ -16,9 +16,10 @@ import {
     UPDATE_CHECK_FOR_UPDATES,
 } from "../constants"
 import CONFIG from "../config"
+import getCurrencyData from "./currency"
 
 //contextBridge.exposeInMainWorld("platform", )
-contextBridge.exposeInMainWorld('darkMode', darkMode)
+contextBridge.exposeInMainWorld("darkMode", darkMode)
 
 contextBridge.exposeInMainWorld("heynote", {
     platform: {
@@ -60,6 +61,10 @@ contextBridge.exposeInMainWorld("heynote", {
         ipcRenderer.invoke("settings:set", settings)
     },
 
+    async getCurrencyData() {
+        return await getCurrencyData()
+    },
+
     onSettingsChange(callback) {
         ipcRenderer.on(SETTINGS_CHANGE_EVENT, (event, settings) => callback(settings))
     },

src/currency.js

@@ -0,0 +1,17 @@
+let currenciesLoaded = false
+export async function loadCurrencies() {
+    const data = await window.heynote.getCurrencyData()
+    if (!currenciesLoaded)
+        math.createUnit(data.base, {override:currenciesLoaded, aliases:[]})
+    Object.keys(data.rates)
+        .filter(function (currency) {
+            return currency !== data.base
+        })
+        .forEach(function (currency) {
+            math.createUnit(currency, {
+                definition: math.unit(1 / data.rates[currency], data.base),
+                aliases: [],
+            }, {override: currenciesLoaded})
+        })
+    currenciesLoaded = true
+}

src/editor/block/math.js

@@ -49,7 +49,7 @@ function mathDeco(view) {
                 // get math.js parser and cache it for this block
                 let parser = mathParsers.get(block)
                 if (!parser) {
-                    parser = math.parser()
+                    parser = window.math.parser()
                     mathParsers.set(block, parser)
                 }
                 

src/main.js

@@ -2,6 +2,7 @@ import './css/application.sass'
 
 import { createApp } from 'vue'
 import App from './components/App.vue'
+import { loadCurrencies } from './currency'
 
 
 const app = createApp(App)
@@ -10,3 +11,11 @@ app.mount('#app').$nextTick(() => {
     // hide loading screen
     postMessage({ payload: 'removeLoading' }, '*')
 })
+
+
+
+
+// load math.js currencies
+loadCurrencies()
+setInterval(loadCurrencies, 1000 * 3600 * 4)
+