PHP Nested JSON from flat JSON

[Sbbcarl]

I have a database query that provides me the output of some employee data. I want to use this data to pass to a plugin that generates an org chart. There are a few fields in the JSON object that I am pulling down which are:
 

    FirstName
    LastName
    EmployeeID
    ManagerEmployeeID
    Manager Name

The data is returned as flat JSON object with no nesting or coloration between employees and their managers in the hierarchy.

Since I am unable to change the output of the source data (the database query), I am trying to figure out a way to nest the data so that the JSON output becomes a nested output.

My goal is to take this array and nest it based on the ManagerID and EmployeeID so I can make a tree hierarchy.

**Example Data:**

 

•    Tom Jones
       o    Alice Wong
       o    Tommy J.
•    Billy Bob
       o    Rik A.
         ♣    Bob Small
         ♣    Small Jones
       o    Eric C.

**My flat data example:**
 

        {
            "FirstName": "Tom"
            "LastName": "Jones"
            "EmployeeID": "123"
            "ManagerEmployeeID": ""
            "Manager Name": ""
        },
        {
            "FirstName": "Alice"
            "LastName": "Wong"
            "EmployeeID": "456"
            "ManagerEmployeeID": "123"
            "Manager Name": "Tom Jones"
        },
        {
            "FirstName": "Tommy"
            "LastName": "J."
            "EmployeeID": "654"
            "ManagerEmployeeID": "123"
            "Manager Name": "Tom Jones"
        },
        {
            "FirstName": "Billy"
            "LastName": "Bob"
            "EmployeeID": "777"
            "ManagerEmployeeID": ""
            "Manager Name": ""
        },
        {
            "FirstName": "Rik"
            "LastName": "A."
            "EmployeeID": "622"
            "ManagerEmployeeID": "777"
            "Manager Name": "Billy Bob"
        },
        {
            "FirstName": "Bob"
            "LastName": "Small"
            "EmployeeID": "111"
            "ManagerEmployeeID": "622"
            "Manager Name": "Rik A."
        },
        {
            "FirstName": "Small"
            "LastName": "Jones"
            "EmployeeID": "098"
            "ManagerEmployeeID": "622"
            "Manager Name": "Rik A"
        },
        {
            "FirstName": "Eric"
            "LastName": "C."
            "EmployeeID": "222"
            "ManagerEmployeeID": "777"
            "Manager Name": "Billy Bob"
        }

    

**Example Desired Output:**

    
    [
      {
        "FirstName": "Tom",
        "LastName": "Jones",
        "EmployeeID": "123",
        "ManagerEmployeeID": "",
        "Manager Name": "",
        "employees": [
          {
            "FirstName": "Alice",
            "LastName": "Wong",
            "EmployeeID": "456",
            "ManagerEmployeeID": "123",
            "Manager Name": "Tom Jones"
          },
          {
            "FirstName": "Tommy",
            "LastName": "J.",
            "EmployeeID": "654",
            "ManagerEmployeeID": "123",
            "Manager Name": "Tom Jones"
          }
        ]
      },
      {
        "FirstName": "Billy",
        "LastName": "Bob",
        "EmployeeID": "777",
        "ManagerEmployeeID": "",
        "Manager Name": "",
        "employees": [
          {
            "FirstName": "Rik",
            "LastName": "A.",
            "EmployeeID": "622",
            "ManagerEmployeeID": "777",
            "Manager Name": "Billy Bob",
            "employees": [
              {
                "FirstName": "Bob",
                "LastName": "Small",
                "EmployeeID": "111",
                "ManagerEmployeeID": "622",
                "Manager Name": "Rik A."
              },
              {
                "FirstName": "Small",
                "LastName": "Jones",
                "EmployeeID": "098",
                "ManagerEmployeeID": "622",
                "Manager Name": "Rik A"
              }
            ]
          },
          {
            "FirstName": "Eric",
            "LastName": "C.",
            "EmployeeID": "222",
            "ManagerEmployeeID": "777",
            "Manager Name": "Billy Bob"
          }
        ]
      }
    ]

Essentially I am trying to create a nested JSON output from a flat object using the `EmployeeID` and `ManagerEmployeeID` as the links between the two.

What is the best way to solve something like this with PHP?

 

I have this code working in a Javascript function but I am pretty new to PHP and not sure what similarities there are to re-write the function in PHP.

 

https://jsfiddle.net/87ztvk8m/

Edited May 16, 2017 by Sbbcarl

[requinix]

It'll be easier to work this into the code you already have than to give you a bunch of stuff and have you adapt it. What is your code?