import { Component, ViewChild, ViewContainerRef, ComponentFactoryResolver, ComponentRef, ComponentFactory } from '@angular/core';
import { ReactiveFormsModule, FormsModule, Validators, FormBuilder, FormGroup, FormControl } from '@angular/forms';
import * as json from '../assets/questions.json';

import { QuestionComponent } from './question/question.component';
import { MainQuestionComponent } from './main-question/main-question.component';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css'],
  providers: []
})
export class AppComponent implements OnInit {
  title = 'Form Builder';

  questions : any;
  main_index:number = 0;

  mainQuestionComponents = [];
  questionComponents = [];

  mainQuestionsComponentRef: any;

  ngOnInit() {
    this.questions = json.default;
  }

  select_questions_by_level(main_index, parent_level) {
    var possible_questions = [];

    for (let i = 0; i < this.questions[main_index].questions.length; i++) {
      if (this.questions[main_index].questions[i].level == parent_level + 1)
        possible_questions.push(this.questions[main_index].questions[i])
    }

    if (this.questionComponents.length > 0) {
      for (let i = 0; i < this.questionComponents.length; i++) {
        for (let j = 0; j <= possible_questions.length - 1; j++){
          if (possible_questions[j].content == this.questionComponents[i].instance.question) {
            possible_questions.splice(j--,1);
          }
        }
      }
    }
    return possible_questions;
  }

  get_key(main_index, question) {
    var key;

    for (let i = 0; i < this.questions[main_index].questions.length; i++) {
      if (this.questions[main_index].questions[i].content == question)
        key = i;
    }
    return key;
  }

  get_sequence(main_index, parent, child) {
    var previous_key = this.get_key(0, parent),
    actual_key = this.get_key(0, child),
    levels = [];

    for (let i = previous_key; i <= actual_key; i++) {
      levels.push(this.questions[main_index].questions[i].level);
    }

    if (levels[0] != levels[1])
      return true;
    return false;
  }

  @ViewChild('questionsContainer', { read: ViewContainerRef }) entry: ViewContainerRef; constructor(private resolver: ComponentFactoryResolver) { }

  createMainQuestionComponent() {
    const factory = this.resolver.resolveComponentFactory(MainQuestionComponent);
    this.mainQuestionsComponentRef = this.entry.createComponent(factory);
    this.mainQuestionComponents.push(this.mainQuestionsComponentRef);
    this.mainQuestionsComponentRef.instance.main_question_index = this.main_index;
    this.mainQuestionsComponentRef.instance.main_question_content = this.questions[this.main_index].main_question.content;
    this.mainQuestionsComponentRef.instance.main_question_type = this.questions[this.main_index].main_question.type;
    this.mainQuestionsComponentRef.instance.main_question_answer = null;
    this.mainQuestionsComponentRef.instance.main_question_childrens_length = 0;
    this.mainQuestionsComponentRef.instance.onMainQuestionAddSubInput.subscribe(msg => this.onMainQuestionAddSubInput(msg));
    this.mainQuestionsComponentRef.instance.onMainQuestionDestroy.subscribe(msg => this.onMainQuestionDestroy(msg));
  }

  createQuestionComponent(main_index, sub_index, last_answer, last_type, question, type, level) {
    const factory = this.resolver.resolveComponentFactory(QuestionComponent);
    this.questionsComponentRef = this.entry.createComponent(factory);
    this.questionComponents.push(this.questionsComponentRef);
    this.questionsComponentRef.instance.main_index = main_index;
    this.questionsComponentRef.instance.question_index = sub_index;
    this.questionsComponentRef.instance.last_answer = last_answer;
    this.mainQuestionsComponentRef.instance.question_answer = null;
    this.questionsComponentRef.instance.last_type = last_type;
    this.questionsComponentRef.instance.question = question;
    this.questionsComponentRef.instance.type = type;
    this.questionsComponentRef.instance.level = level;
    this.questionsComponentRef.instance.onQuestionAddSubInput.subscribe(msg => this.onQuestionAddSubInput(msg));
    this.questionsComponentRef.instance.onQuestionDestroy.subscribe(msg => this.onQuestionDestroy(msg));
  }

  addMainQuestion() {
    if (this.main_index < this.questions.length) {
      this.createMainQuestionComponent();
      this.main_index++;
    }
  }

  onMainQuestionAddSubInput(main_index) {
    var last_answer, last_type, question, type, level;
    switch (this.mainQuestionComponents[main_index].instance.main_question_type) {
      case 'select':
    	  if (this.mainQuestionComponents[main_index].instance.main_question_answer == 'Yes') {
          let possible = this.select_questions_by_level(main_index, 0);
          if (possible.length > 0) {
            let data = possible[0],
            last_answer = this.mainQuestionComponents[main_index].instance.main_question_answer,
            last_type = this.mainQuestionComponents[main_index].instance.main_question_type,
            question = data.content,
            type = data.type;

            this.createQuestionComponent(main_index, this.mainQuestionComponents[main_index].instance.main_question_childrens_length, last_answer, last_type, question, type, 1);
            this.mainQuestionComponents[main_index].instance.main_question_childrens_length++;
          }
    	  }
        break;
      default:
        let possible = this.select_questions_by_level(main_index, 0);
        if (possible.length > 0) {
          let data = possible[0],
          last_answer = this.mainQuestionComponents[main_index].instance.main_question_answer,
          last_type = this.mainQuestionComponents[main_index].instance.main_question_type,
          question = data.content,
          type = data.type;

          this.createQuestionComponent(main_index, this.mainQuestionComponents[main_index].instance.main_question_childrens_length, last_answer, last_type, question, type, 1);
          this.mainQuestionComponents[main_index].instance.main_question_childrens_length++;
        }
        break;
    }
  }

  onQuestionAddSubInput(data) {
    if (this.select_questions_by_level(data.main_index, data.level).length > 0) {
      let possible = this.select_questions_by_level(data.main_index, data.level)[0],
      last_object = null;
      for (let i = 0; i < this.questionComponents.length; i++) {
        if (this.questionComponents[i].instance.main_index == data.main_index && this.questionComponents[i].instance.question_index == data.question_index)
          last_object = this.questionComponents[i];
      }
      if (this.get_sequence(data.main_index, last_object.instance.question, possible.content)) {
        let last_answer = last_object.instance.question_answer,
        last_type = last_object.instance.type,
        question = possible.content,
        type = possible.type,
        level = possible.level;

        this.createQuestionComponent(data.main_index, this.mainQuestionComponents[data.main_index].instance.main_question_childrens_length, last_answer, last_type, question, type, level);
        this.mainQuestionComponents[data.main_index].instance.main_question_childrens_length++;
      }
    }
  }

  onMainQuestionDestroy(main_index) {
    this.mainQuestionComponents[main_index].destroy();
    for (let i = 0; i < this.questionComponents.length; i++) {
      if (this.questionComponents[i].instance.main_index == main_index)
      	this.questionComponents[i].destroy();
    }
  }

  onQuestionDestroy(data) {
    for (let i = 0; i < this.questionComponents.length; i++) {
      if (this.questionComponents[i].instance.main_index == data.main_index && this.questionComponents[i].instance.question_index == data.question_index)
        this.questionComponents[i].destroy();
    }
  }
}