Driver Change in Vehicle name using MongoDB query

driver_timeline.js

[
  {
    $match: {
      driver_id: ObjectId(
        "656d9b8c6a91175eb8c3ea3a"
      ),
      vehicle_name: { $nin: ["", "0", null] },
      // vehicle_name: "5405"
    },
  },
  {
    $project: {
      driver_id: 1,
      start_time: 1,
      end_time: 1,
      vehicle_name: 1,
    },
  },
  {
    $sort: {
      start_time: 1,
    },
  },
  // calculate change in vehicle_name, keeping backward and forward change
  // so we can later keep last documents end_time
  {
    $setWindowFields: {
      sortBy: { start_time: 1 },
      output: {
        backward: {
          $push: {
            name: "$vehicle_name",
            end_time: "$end_time",
          },
          window: { documents: [-1, "current"] },
        },
        forward: {
          $push: {
            name: "$vehicle_name",
            end_time: "$end_time",
          },
          window: { documents: ["current", 1] },
        },
      },
    },
  },
  {
    $match: {
      $expr: {
        $or: [
          { $eq: [{ $size: "$backward" }, 1] }, // first document will have only one entry
          { $eq: [{ $size: "$forward" }, 1] }, // last document will have only one entry
          {
            // keep only documents where there is a change in vehicle_name
            $ne: [
              { $first: "$backward.name" },
              { $last: "$backward.name" },
            ],
          },
        ],
      },
    },
  },
  {
    // add fields for end time
    $addFields: {
      previousDocTime: { $first: "$backward" },
      currentDocTime: { $last: "$backward" },
    },
  },
  {
    $project: {
      forward: 0,
    },
  },
  {
    // fetch previousDocTime from next document in dates key
    $setWindowFields: {
      sortBy: { start_time: 1 },
      output: {
        dates: {
          $push: "$previousDocTime",
          window: { documents: ["current", 1] },
        },
      },
    },
  },
  {
    // take last end_time from dates
    $addFields: {
      end_time: {
        $last: "$dates.end_time",
      },
    },
  },
  {
    // remove extra fields
    $unset: [
      "pair",
      "previousDocTime",
      "currentDocTime",
      "dates",
      "backward",
    ],
  },
  {
    $match: {
      $expr: { $ne: ["$start_time", "$end_time"]}
    }
  }
]