I have an array of objects that look similar to this

[ { lastseen: 1640694661000, value: "test1"}, { lastseen: 1640696227000, value: "test2"}]

New object that I am trying to insert is

{ lastseen: 1640695661564, value: "test1"}

I need to push this into a new array based on its recent last seen when the values are same . Only unique values should be present in the final array and that has recent lastseen

The output should look like

newArr = [ { lastseen: 1640695661564, value: "test1"}, { lastseen: 1640696227000, value: "test2"} ]

In this case test1 with lastseen 1640695661564 is recent and only one such object is present in the final array

Code that I tried

function uniqueAndInsert(currArr, input){
   const idx = currArr.findIndex((obj) => {
    obj.lastseen < input.lastseen;
   });
   if(idx!==-1){
      currArr.splice(idx, 0, input);
   }
   else{
     currArr.splice(0);
     currArr.push(input);
   }
   return currArr;
}

CodePudding user response：

Try this one

function replaceArrayItemByValue(array = [], item) {
  const hasNewItem = array.some(e => e.value === item.value)

  if (!hasNewItem) return [...array, item]

  return array.map(arrayItem => {
    const isItemToReplace = arrayItem.value === item.value

    if (isItemToReplace) return item

    return arrayItem
  })
}

console.log(
  replaceArrayItemByValue(
    [
      { value: '1', time: 1 },
      { value: '2', time: 2 }
    ],
    {
      value: '1',
      time: 'new time'
    }
  )
)

console.log(
  replaceArrayItemByValue(
    [
      { value: '1', time: 1 },
      { value: '2', time: 2 }
    ],
    {
      value: '3',
      time: 'new time'
    }
  )
)

CodePudding user response：

There are 3 cases to handle. 1) input is recent than current data (update data) 2) input is not recent than current data (no change) 3) input does not exist in current data (add data).

function uniqueAndInsert(currArr, input) {
  const item = currArr.find(({ value }) => value === input.value);
  if (item && item.lastseen >= input.lastseen) {
    // data is up to date, no changes just return original array
    return currArr;
  }
  // filter the same value data if exist and add input
  return currArr.filter(({ value }) => value !== input.value).concat(input);
}

// alternatively, to do it one iteration
function uniqueAndInsert2(currArr, input) {
  const output = [];
  let exist = false;
  currArr.forEach(({ value, lastseen }) => {
    if (value === input.value) {
      output.push({ value, lastseen: Math.max(input.lastseen, lastseen) });
      exist = true;
    } else {
      output.push({ value, lastseen });
    }
  });
  if (!exist) {
    output.push(input);
  }
  return output;
}