//sort
let persons = [
    {name: "Иван", age: 17},
    {name: "Мария", age: 35},
    {name: "Алексей", age: 73},
    {name: "Яков", age: 12},
    {name: "Яков", age: 1132},
    {name: "Яков", age: 22},
    {name: "Яков", age: 142},
]

function arrsort(arr, prop, incline=true) {
   if (arr.length < 2) {
       return arr
   }

   let mid = Math.floor(arr.length / 2)
   let equ = arr.filter(value => value[prop] === arr[mid][prop])

   let more = incline? arr.filter(value => value[prop] > arr[mid][prop]) :
                    (arr.filter(value => value[prop] < arr[mid][prop])).reverse()

   let less = incline? arr.filter(value => value[prop] < arr[mid][prop]) :
                    (arr.filter(value => value[prop] > arr[mid][prop])).reverse()

    return [...arrsort(less, prop, incline), ...equ, ...arrsort(more, prop, incline)]
}

console.log(arrsort(persons, 'age', false))

//array map
let mapped = ["1", {}, null, undefined, "500", 700].map((elem) => {
    return isNaN(elem) || typeof elem === 'object'? elem : +elem
})
console.log(mapped)

//array reduce
let reduced = ["0", 5, 3, "string", null, 2, 100].reduce((prev, curr)=> {
    let sum = typeof prev === 'number'? prev : 1
    let isPresent = false;

    (function() {
        isPresent = typeof prev === 'number' || typeof curr === 'number'? true : false
        if(typeof curr === 'number') {
            sum = sum * curr
        }
    })();

    return isPresent? sum : 0
})
console.log(reduced)

//object filter
let phone = {
    brand: "meizu",
    model: "m2",
    ram: 2,
    color: "black",
};

function objectFilter(obj, f) {
    let filtered = {}
    for(let key in obj) {
        if(f(key, obj[key])) {
            filtered[key] = obj[key]
        }
    }
    return filtered
}

let filtered = objectFilter(phone, (key, value) => key === 'model' || value === 'black')
console.log(filtered)

//object map
function objectMap(object, f) {
    let mapped = {}
    for(let key in object) {
        let temp = f(key, object[key])
        for(let prop in temp) {
            console.log('biba',prop, temp[prop])
            mapped[prop] = temp[prop]
        }
    }
    return mapped
}

console.log(objectMap({name: "Иван", age: 17}, function(key,value){
    var result = {};
    result[key+"_"] = value + "$";
    console.log('ras', result)
    return result;
}))

//sum
function sum(initial, step, members) {
    var res = initial
    var memb = members
    if(memb === 0) {
        return res
    } else {
        return sum(res + step, step, memb-1)
    }
}

console.log('sum', sum(5, 3, 10))

//HTML Tree
// blue belt
class Markup {
    constructor(tagName, [...nestedTags]=[], {...attrs}={}, text='') {
        this.tagName = tagName,
        this.attrs = attrs
        this.text = text
        this.nestedTags = nestedTags
    }
}

let md3 = new Markup(
                'table', 
                [
                    new Markup(
                        'tr', 
                        [
                            new Markup(
                                'td', 
                                undefined, 
                                {disabled:true}, 
                                'some text'
                            ),
                            new Markup(
                                'td', 
                                undefined, 
                                undefined, 
                                'some text2'
                            )
                        ]
                    ),
                    new Markup(
                        'tr', 
                        [
                            new Markup(
                                'td', 
                                [ 
                                    new Markup(
                                        'div', 
                                        [
                                            new Markup(
                                                'p', 
                                                undefined, 
                                                {disabled:true}, 
                                                'some textp'
                                            ),
                                            new Markup(
                                                'p', 
                                                undefined, 
                                                {style:'font-weight:800;color:red'}, 
                                                'some textp'
                                            )
                                        ]
                                    )
                                ],
                                {style:'background-color:purple;color:white;'},
                                'some text div'
                            ),
                            new Markup(
                                'td', 
                                undefined, 
                                {class:'someclass'}, 
                                'some text4'
                            )
                        ]
                    )
                ],
                {border: 1, style:"color:'red';"}
            )

function stringifyMdObject(Md_obj) {
    let str = ''
    for(let key in Md_obj) {
        if(key === 'tagName') {
            str += `<${Md_obj[key]}`
            if(Md_obj.attrs.length !== 0) {
                continue;
            } else {
                str += `>`
            }
        }

        if(key === 'nestedTags') {
            for(let i = 0; i < Md_obj[key].length; i++) {
                str += stringifyMdObject(Md_obj[key][i])
            }            
        }

        if(key === 'attrs' && Md_obj[key].length !== 0) {
            for(let i in Md_obj.attrs) {
                str += ` ${i}="${Md_obj.attrs[i]}"`
            }
            str += `>`
        }
    }
    str += `${Md_obj.text}`
    str += `</${Md_obj.tagName}>`

    return str
}

document.write(stringifyMdObject(new Markup('h2',[new Markup('span',undefined,{style:'color:blue;'},'Blue ')],undefined,'belt')))
document.write(stringifyMdObject(md3))