code refactor to use ProblemParser and CaseParser.

Author: ecgan

2018/qualification/2-trouble-sort/solution.js

@@ -1,58 +1,8 @@
 'use strict'
 
-//////////////
-
-// call parse() to read the inputs and return list of problems / test cases. 
-function parse() {
-  const readline = require('readline');
-  let t = 0;
-  let currentT = 0;
-  let readState = 't'
-  let probs = []
-
-  const rl = readline.createInterface({
-    input: process.stdin,
-    output: process.stdout
-  });
-
-  rl.on('line', (line) => {
-    switch (readState) {
-      case 't': {
-        t = parseInt(line)
-        readState = 'num'
-        break
-      }
-      case 'num': {
-        readState = 'list'
-        break
-      }
-      case 'list': {
-        let prob = new Problem()
-        prob.numbers = line.split(' ').map(num => parseInt(num))
-        probs.push(prob)
-        currentT += 1
-        readState = 'num'
-        break;
-      }
-    }
-
-    if (currentT === t) {
-      rl.close()
-    }
-  })
-    .on('close', () => {
-      proc(probs)
-    })
-}
-
-function proc(probs) {
-  for (let index = 0; index < probs.length; index++) {
-    const result = solve(probs[index]);
-    console.log(`Case #${index + 1}: ${result}`)
-  }
-}
-
-//////// Solve /////////
+//
+// solve
+//
 function solve(prob) {
   let firstArr = prob.numbers.reduce((acc, val, index, array) => {
     if (index % 2 === 0) {
@@ -113,16 +63,121 @@ function gotProblem(array) {
   return false
 }
 
-////////////////////////
+//
+// processCases
+//
+function processCases(probs) {
+  for (let index = 0; index < probs.length; index++) {
+    const result = solve(probs[index]);
+    console.log(`Case #${index + 1}: ${result}`)
+  }
+}
+
+//
+// CaseParser
+//
+class CaseParser {
+  constructor() {
+    this.numbers = []
+    this.state = 'num'
+  }
+
+  readline(line) {
+    switch(this.state) {
+      case 'num': {
+        // the line is useless.
+        this.state = 'list'
+        break
+      }
 
-function Problem() {
-  this.numbers = []
+      case 'list': {
+        this.numbers = line.split(' ').map(num => parseInt(num))
+        this.state = 'done'
+        break
+      }
+    }
+  }
+
+  isComplete() {
+    return (this.state === 'done')
+  }
+
+  getCase() {
+    return {
+      numbers: this.numbers
+    }
+  }
 }
 
-//////////////
+//
+// ProblemParser
+//
+class ProblemParser {
+  constructor() {
+    this.t = 0
+    this.currentT = 0
+    this.cases = []
+    this.caseParser = new CaseParser()
+    this.state = 't'
+  }
+
+  readline(line) {
+    switch (this.state) {
+      case 't': {
+        this.t = parseInt(line)
+        this.state = 'case'
+        break
+      }
+    
+      case 'case': {
+        this.caseParser.readline(line)
+
+        if (this.caseParser.isComplete()) {
+          this.cases.push(this.caseParser.getCase())
+          this.currentT += 1
+          this.caseParser = new CaseParser()
+        }
+
+        break
+      }
+    }
 
+    if (this.currentT === this.t) {
+      this.state = 'done'
+    }
+  }
+
+  isComplete() {
+    return (this.state === 'done')
+  }
+
+  getCases() {
+    return this.cases
+  }
+}
+
+//
+// Main
+//
 function main() {
-  parse()
+  const readline = require('readline')
+  const problemParser = new ProblemParser()
+
+  const rl = readline.createInterface({
+    input: process.stdin,
+    output: process.stdout
+  })
+
+  rl.on('line', (line) => {
+    problemParser.readline(line)
+
+    if (problemParser.isComplete()) {
+      rl.close()
+    }
+  }).on('close', () => {
+      processCases(problemParser.getCases())
+    }
+  )
 }
 
 if (!module.parent) {