摘要：數組中連續的一個或多個整數組成一個子數組，每個子數組都有一個和。求所有子數組的和的最大值，要求時間復雜度為。輸出結果類數組轉成數組直接遍歷這種方法是借用了數組原型中的方法，返回一個數組方法從一個類似數組或可迭代對象中創建一個新的數組實例。

import "../css/detail.css";

// 找到字符串中重復次數最多的字符
function findMax(str) {
  let maxChar = "";
  let maxValue = 1;

  if (!str.length) return;
  let arr = str.replace(/s/g, "").split("");
  let obj = {};
  for (let i = 0; i < arr.length; i++) {
    if (!obj[arr[i]]) {
      obj[arr[i]] = 1;
    } else {
      obj[arr[i]]++;
    }
  }
  let keys = Object.keys(obj);
  for (let j = 0; j < keys.length; j++) {
    if (obj[keys[j]] > maxValue) {
      maxValue = obj[keys[j]];
      maxChar = keys[j];
    }
  }

  return {
    maxChar, maxValue
  }
}

function findMax1() {
  let maxChar = "";
  let maxValue = 1;
  let h = {};
  if (!str.length) return;
  let arr = str.replace(/s/g, "").split("");
  for (let i = 0; i < arr.length; i++) {
    let a = arr[i];
    h[a] === undefined ? h[a] = 1 : h[a]++;
    if (h[a] > maxValue) {
      maxChar = a;
      maxValue = h[a];
    }
  }
  return {
    maxChar, maxValue
  }
}

function findMax2() {
  let maxChar = "";
  let maxValue = 1;
  if (!str.length) return;
  let arr = str.replace(/s/g, "").split("");
  let obj = arr.reduce((acc, curVal) => {
    acc[curVal] ? acc[curVal]++ : acc[curVal] = 1;
    if (acc[curVal] > maxValue) {
      maxChar = curVal;
      maxValue = acc[curVal];
    }
    return acc;
  }, {}) 
  return {
    maxChar, maxValue
  }
}

/* 
  d 任意一個數字，0~9 中的任意一個
  w 任意一個字母或數字或下劃線，也就是 A~Z,a~z,0~9,_ 中任意一個
  s 包括空格、制表符、換頁符等空白字符的其中任意一個
. 小數點可以匹配除了換行符（
）以外的任意一個字符 
*/
function findMax3(str) {
  let maxChar = "";
  let maxValue = 1;
  if (!str.length) return;
  let arr = str.replace(/s/g, "").split("");
  let obj = {};
  str.replace(/s/g, "").replace(/(w)/g, (word, p) => {
    obj[p] ? obj[p]++ : obj[p] = 1;
    if (obj[p] > maxValue) {
      maxValue = obj[p];
      maxChar = p;
    }
  });
  return {
    maxChar, maxValue
  }

}

function findMax4(str) {
  let maxChar = "";
  let maxValue = 1;
  if (!str.length) return;
  let arr = str.replace(/s/g, "").split("");
  Array.prototype.getMost = function() {
    let obj = this.reduce((acc, cur) => {
      acc[cur] ? acc[cur]++ : acc[cur] = 1;
      acc.max = acc[cur] > acc.max ? acc[cur] : acc.max;
      acc.key = acc[cur] > acc.max ? cur : acc.key;
      return acc;
    }, {});
    return obj;
  }
  // return arr.getMost();
}

const str = "this is a test 222222 ts project. skajdf; 222sldjfwel p"

const reducer = (accumulator, currentValue, b, c) => {
  let obj = {};
  obj[b] = currentValue;
  return obj;
}
const array1 = [1, 2, 3, 4];
// console.log(array1.reduce(reducer));

console.log(findMax(str));
console.log("findMax1", findMax4(str));

/**
 * 輸入一個整形數組，數組里有正數也有負數。數組中連續的一個或多個整數組成一個子數組，每個子數組都有一個和。 求所有子數組的和的最大值，要求時間復雜度為O(n)。
 */
function findMaxSubArr(arr) {
  console.log(arr)
  let max = arr[0];
  let currSum = 0;
  for (let i = 0; i < arr.length; i++) {
    if (currSum < 0) {
      currSum = arr[i];
    } else {
      currSum += arr[i]; 
    }
    if (currSum > max) {
      max = currSum;
    }
  }
  return max;
}

// console.log("maxsubarr", findMaxSubArr([1, -2, 3, 10, -4, 7, 2, -5]));

// 輸出結果
console.log("begin");
setTimeout(() => {
  console.log("settimeout 1")
  Promise.resolve().then( () => {
    console.log("promise 1")
    setTimeout(() => {
      console.log("settimeout 2");
    });
  }).then(() => {
    console.log("promise 2");
  })
}, 0);
console.log("end");

/**
 * 類數組轉成數組
 */
const nodes = document.querySelectorAll("div");
// nodes.map(item => {});

// 1.for直接遍歷

// 2.這種方法是借用了數組原型中的slice方法，返回一個數組
Array.prototype.slice.call(nodes).map(item => {});
[].slice.call(nodes).map(item => {console.log()});

// 3.Array.from() 方法從一個類似數組或可迭代對象中創建一個新的數組實例。
Array.from(nodes).map(item => {})

// 4.同樣是ES6中新增的內容，擴展運算符（…）也可以將某些數據結構轉為數組
const nodeList = [...nodes];
function getlist(a,b,c,d) {
  // console.log(arguments);
  // console.log([...arguments][0])
}
getlist(11, 2, 3, 4);

// 使用reduce方法實現forEach、map、filter
const arr1 = [12, 21, 3];
const arr2 = arr1.map(function(item) {
  // console.log(this, item)
  return item*2
}, { msg: "mapping" })
// console.log(arr1, arr2)

// github上的
Array.prototype.selfMap = function () {
  const ary = this
  const result = []
  const [ fn, thisArg ] = [].slice.call(arguments)
  if (typeof fn !== "function") {
    throw new TypeError(fn + "is not a function")  
  }
  for (let i = 0; i < ary.length; i++) {
    result.push(fn.call(thisArg, ary[i], i, ary))
  }
  return result
}

Array.prototype.reduceMap = function (fn, thisArg) {
  // return (list) => {
      // 不怎么愿意寫下面這兩個判斷條件
      const list = this
      if (typeof fn !== "function") {
          throw new TypeError(fn + "is not a function")  
      }
      if (!Array.isArray(list)) {
          throw new TypeError("list must be a Array")
      }
      if (list.length === 0) return []
      return list.reduce((acc, value, index) => {
          return acc.concat([ fn.call(thisArg, value, index, list) ])
      }, [])
  // }
}

// mine
Array.prototype.imitateMap = function () {
  const list = this;
  const result = []
  const [fn, thisArg] = [].slice.call(arguments)
  if (typeof fn !== "function") {
    throw new TypeError(fn + "is not a function");
  }
  for (let i = 0; i < list.length; i++) {
    result.push(fn.call(thisArg, list[i], i, list));
  }
  return result;
}

Array.prototype.imitateReduceMap = function () {
  const list = this;
  const result = []
  const [fn, thisArg] = [].slice.call(arguments)
  if (typeof fn !== "function") {
    throw new TypeError(fn + "is not a function");
  }
  if (!Array.isArray(list)) {
    throw new TypeError(list + "is not a Array");
  }
  return list.reduce((acc, curValue, index) => {
    return acc.concat([fn.call(thisArg, curValue, index, list)]);
  }, [])
}

const imitateReduceMap1 = function (fn, thisArg) {
  return (list) => {
    const result = []
    if (typeof fn !== "function") {
      throw new TypeError(fn + "is not a function");
    }
    if (!Array.isArray(list)) {
      throw new TypeError(list + "is not a Array");
    }
    return list.reduce((acc, curValue, index) => {
      return acc.concat([fn.call(thisArg, curValue, index, list)]);
    }, [])
  }
}

console.log("imitateMap", arr1, arr1.imitateMap(function(item) {
  console.log("imitateMap this", this)
  return item + 1
}, { msg: "mapping" }) )
console.log("imitateReduceMap", [ 1, 2, 3 ].imitateReduceMap(x => x + 1));
console.log("imitateReduceMap1", imitateReduceMap1(x => x + 1)([ 1, 2, 3 ]));

/**
 * 實現repeat方法
 */
function repeat(func, times, wait) {
  return (str) => {
    let count = 0;
    const timer = setInterval(() => {
      if (count < times) {
        // func.call(this, str);
        count++;
      } else {
        clearInterval(timer);
      }
      
    }, wait);
  }
}

const repeatFunc = repeat(alert, 3, 2000)

repeatFunc("helloworld");

/**
 * 實現一個簡單的雙向綁定
 * 1.發布-訂閱模式
 * 2.臟值檢測
 * 3.數據劫持
 * Vue.js 采用的是 數據劫持+發布/訂閱模式 的方式，通過 Object.defineProperty() 來劫持各個屬性的 setter/getter， 在數據變動時發布消息給訂閱者（Wacther）, 觸發相應的監聽回調
 */
// 基于Object.defineProperty 實現數據劫持，利用了對Vue.js實現雙向綁定的思想
const obj = {}
Object.defineProperty(obj, "txt",{
  get:function(){
    return obj
  },
  set:function(newValue){
    document.getElementById("txt").value = newValue
    document.getElementById("show-txt").innerHTML = newValue
  }
})
document.addEventListener("keyup", function(e){
  obj.txt = e.target.value
})