something along the lines
var obj_1 = {id:1, text:"Title 1", checked: false, unitId:0, line: 0};
var obj_2 = {id:2, text:"Title 1.1", checked: false, unitId:1, line: 0};
var obj_3 = {id:3, text:"Title 1.2", checked: false, unitId:1, line: 1};
var obj_4 = {id:4, text:"Title 1.1.1", checked: false, unitId:0, line: 1};
var obj_5 = {id:5, text:"Title 2", checked: false, unitId:0, line: 1};
var obj_list = [obj_1,obj_2,obj_3,obj_4,obj_5];
let result = obj_list.reduce((acc,o)=>{
let unitId = o.unitId;
let cur = acc[unitId];
if(!cur){
cur = {checked:false, text: `Unit ${unitId + 1}`, children:[]};
acc[unitId] = cur;
}
cur.children.push(o);
return acc;
},{});
result = Object.values(result).map(v=>{
let dic = v.children.reduce((acc, o)=>{
let lineId = o.line;
let cur = acc[lineId];
if(!cur){
cur = {checked:false, text: `Line ${String.fromCharCode(lineId+65)}`, children:[]};
acc[lineId] = cur;
}
cur.children.push(o);
return acc;
},{})
v.children = Object.values(dic);
return v;
})
result = {text:'Main Root', checked:false, children:result}
console.log(JSON.stringify(result,null,2))
solved Javascript array of object to tree structure