130242014017-蔡志峰-第3次实验

const fs = require("fs");
/**
* kwic程序设计
* 管道/过滤器风格
* 输入策略: 从文件中读取
* 行移动策略: 每输入一行移动一次
* 行存储策略: 显式存储
*/

/**
* 过滤器基对象 
* 为过滤器提供链表节点属性
*/
class Filter {
constructor(nextFilter) {
this._checkOptions(nextFilter);
this.next = nextFilter;
}
_checkOptions(nextFilter) {
if (!nextFilter instanceof Filter) {
throw new TypeError("下一个过滤器必须是过滤器类型!");
}
}
checkInput() {
throw new ReferenceError("这是一个抽象方法");
}
handle(input) {
throw new ReferenceError("这是一个抽象方法");
}
}

class WordsMoveFilter extends Filter {
constructor() {
super();
}
checkInput(data) {
const isStrArr = data.every(item => {
return typeof item === "string";
});

if( !isArray ){
throw new TypeError("数据格式不满足处理条件"); 
}
}
handle(data) {
this.checkInput(data);

let results = [];
for(let i = 0, len = data.length; i < len; i++){

let line = data[ i ];
results.push( line );

let words = line.trim().replace(/\s+/g, " ").split(" ");
let wordCtn = words.length;

while( wordCtn > 1){
words.push(words.shift());
results.push(words.join(" "));
wordCtn--;
}
}

return results;
}
}

class StatementsSorterFilter extends Filter {
constructor() {
super();
}
checkInput(data) {
const isStrArr = data.every(item => {
return typeof item === "string";
});

if( !isStrArr ){
throw new TypeError("数据格式不满足处理条件"); 
}
}
handle(data) {
this.checkInput(data);
let results = [];
results = data.sort();
return results;
}
}

/**
* 管道对象
* 本质上是个单链表
*/
const pipe = {
filterHead: new Filter(),
length: 0,
insertFilter(newFilter, index) {

if (index < 0 || index > this.length) {
throw new RangeError("index超出合理的范围");
}

let filter = this.filterHead;
while (filter.next && index > 0) {
filter = filter.next;
index--;
}

newFilter.next = filter.next;
filter.next = newFilter;

this.length++;
},
appendFilter(filter) {
this.insertFilter(filter, this.length);
},
readDataSouceFromFile(fileName) {

const dataSource = [];

return new Promise(function (resolve, reject) {
const stream = fs.createReadStream(fileName);
stream.on("data", data => {
dataSource.push(data.toString());
});

stream.on("end", function () {
resolve(dataSource);
});
});
},
startFilterAndOuput(dataSource) {
let filter = this.filterHead;
let data = dataSource;

while (filter.next && filter.handle) {
data = filter.handle(data);
filter = filter.next;
}
}
}

pipe.appendFilter(new WordsMoveFilter());
pipe.appendFilter(new StatementsSorterFilter())
pipe.readDataSouceFromFile("example.txt").then(pipe.startFilterAndOuput);

const fs = require("fs");

/**
* kwic程序设计
* 面向对象, 对象之间通过接口来访问数据
*/

class Input {
constructor() {
this.statements = [];
}
read(filename) {
const stream = fs.createReadStream(filename);

stream.on("data", data => {
let statement = data.toString().trim().replace(/\s+/g, " ");
this.statements.push(statement);
});
}
}

class Mover {
constructor() {
this.statements = [];
this.movedStatements = [];
}
setStatements(statements) {
this.statements = statements;
}
moveTheStatementWords() {

for (let i = 0, len = this.statements.length; i < len; i++) {

let line = this.statements[i];
this.movedStatements.push(line);

let words = line.trim().replace(/\s+/g, " ").split(" ");
let wordCtn = words.length;

while (wordCtn > 1) {
words.push(words.shift());
this.movedStatements.push(words.join(" "));
wordCtn--;
}
}
}
}

class Sorter {
constructor() {
this.statements = [];
}
setStatements( statements ){
this.statements = statements;
}
sortStatements() {
this.statements = this.statements.sort()
}
}

class Output {
constructor() {
this.results = [];
}
setSortedStatements(statements) {
this.results = statements;
}
echoResult() {
this.results.forEach((item) => {
console.log(item);
});
}
}

class Kwic {
constructor() {
this.input = new Input();
this.output = new Output();
this.sorter = new StatementsSorter();
this.mover = new StatementWordsMover();
}
run() {
this.input.read();
this.mover.setStatements(this.input.getStatements());
this.mover.movedStatements();
this.sorter.setSortedStatements(this.mover.getStatements());
this.sorter.sortStatements();
this.output.setStatements(this.sortStatements.getStatements());
this.ouput.echoResult();
}
}

let kwic = new Kwic();
kwic.run();