Completed the assignment

index.js

@@ -1 +0,0 @@
-// Write your answer here

package.json

@@ -4,9 +4,22 @@
   "description": "_We're looking at your programming ability. It must not only work, it should be maintainable._",
   "main": "index.js",
   "scripts": {
-    "start": "node index.js",
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "start": "node src/index.js",
+    "test": "jest --coverage --verbose"
   },
+  "bin": "src/index.js",
   "author": "",
-  "license": "ISC"
+  "license": "ISC",
+  "dependencies": {
+    "any-date-parser": "^1.5.3",
+    "axios": "^1.2.0",
+    "commander": "^9.4.1",
+    "cryptocompare": "^1.0.0",
+    "csv-parser": "^3.0.0",
+    "dotenv": "^16.0.3",
+    "node-fetch": "2"
+  },
+  "devDependencies": {
+    "jest": "^29.3.1"
+  }
 }

src/functions/analyze.js

@@ -0,0 +1,27 @@
+const fs = require('fs');
+const csv = require('csv-parser');
+const {
+    convertEpochToDate
+} = require('../helpers/epoch');
+
+const results = []
+
+async function analyse(file, flag) {
+    fs.createReadStream(file)
+        .pipe(csv())
+        .on('data', (data) => results.push(data))
+        .on('end', () => {
+            if(flag == 'coin'){
+                const uniqueCoins = [...new Set(results.map(item => item.token))];
+                return uniqueCoins
+            }
+            else if(flag == 'date'){
+                const lastDate = results[results.length - 1].date
+                const date = convertEpochToDate(lastDate)
+                return date
+            }
+            process.exit(1)
+        });
+}
+
+module.exports = analyse

src/functions/calculate.js

@@ -0,0 +1,62 @@
+const fs = require('fs');
+const csv = require('csv-parser');
+const { getRates } = require('../helpers/rates');
+const {
+    convertDateToEpoch,
+    convertEpochToDate
+} = require('../helpers/epoch');
+
+const results = [], amountStore = {};
+
+async function calculate(file, tokens, date) {
+    let tokenArr = tokens.split(',')
+    const USDConvStore = await getRates(tokenArr);
+
+    function USDConvStoreFn(parentCurreny, value){
+        const ans = value / USDConvStore[parentCurreny]
+        return ans.toFixed(2)
+    }
+
+    let dateToEpoch
+    if(date){
+        dateToEpoch = convertDateToEpoch(date);
+    }
+    let pick = 0
+    fs.createReadStream(file)
+        .pipe(csv())
+        .on('data', (data) => {
+            if(dateToEpoch){
+                if(data.timestamp > dateToEpoch){
+                    results.push(data);
+                    pick++
+                    console.log(pick)
+                }
+            }
+            else{
+                results.push(data);
+            }
+        })
+        .on('end', () => {
+            const uniqueCoins = [...new Set(results.map(item => item.token))];
+            
+            uniqueCoins.forEach(coin => {
+                amountStore[coin] = 0
+            })
+
+            results.map(result => {
+                if (result.transaction_type == "DEPOSIT" && result.token in USDConvStore) {
+                    result.amount = USDConvStoreFn(result.token, result.amount)
+                    amountStore[result.token] += +result.amount
+                }
+                else if(result.transaction_type == "WITHDRAWAL" && result.token in USDConvStore) {
+                    result.amount = USDConvStoreFn(result.token, result.amount)
+                    amountStore[result.token] -= +result.amount
+                }
+            })
+
+            Object.keys(amountStore).forEach(key => amountStore[key] === 0 && delete amountStore[key]);
+            console.table(amountStore)
+        });
+}
+
+module.exports = calculate

src/helpers/epoch.js

@@ -0,0 +1,17 @@
+require('any-date-parser');
+
+function convertDateToEpoch(date) {
+    const ndate = new Date.fromAny(date);
+    const epoch = ndate.getTime();
+    return epoch/1000;
+}
+
+function convertEpochToDate(date) {
+    const ndate = new Date(date*1000);
+    return ndate;
+}
+
+module.exports = {
+    convertDateToEpoch,
+    convertEpochToDate
+};

src/helpers/rates.js

@@ -0,0 +1,15 @@
+const cc = require('cryptocompare')
+cc.setApiKey(process.env.CRYPTO_COMPARE_API_KEY);
+
+const getRates = async (rateList) => {
+    try {
+        return cc.price('USD', rateList)
+    }
+    catch (error) {
+        console.log(error);
+    }
+}
+
+module.exports = {
+    getRates
+}

src/index.js

@@ -0,0 +1,31 @@
+#!/bin/sh
+require('dotenv').config();
+global.fetch = require('node-fetch')
+
+const {program} = require('commander');
+const calculate = require('./functions/calculate');
+
+program
+    .version('0.0.1')
+    .argument('<file>', 'transactions to analyse')
+    .option('-t, --tokens <tokens>', 'token/s to evaluate')
+    .option('-d, --date <date>', 'date to start from')
+    .parse();
+
+const options = program.opts();
+const [file] = program.args;
+
+if (!file) {
+    console.log('No transactions file provided');
+    process.exit(1);
+}
+
+if (!options.tokens) {
+    console.log('No token specified. So will analyse all tokens');
+}
+
+if (!options.date) {
+    console.log('No date specified. So will analyse from the beginning');
+}
+
+calculate(file, options.tokens, options.date);