import {
  Component,
  OnInit,
  Input,
  Output,
  EventEmitter,
  ViewChild,
  ContentChild,
  TemplateRef,
  AfterViewInit,
  ChangeDetectorRef,
  OnDestroy,
  ElementRef
} from '@angular/core';

import { ucapAnimations } from '@ucap-webmessenger/ui';

import { NGXLogger } from 'ngx-logger';
import { FileUtil } from '@ucap-webmessenger/core';
import { FormGroup, FormBuilder, Validators } from '@angular/forms';

interface Content {
  contentType: 'text' | 'image' | 'attachment';
  content: string;
}

@Component({
  selector: 'ucap-message-write',
  templateUrl: './write.component.html',
  styleUrls: ['./write.component.scss'],
  animations: ucapAnimations
})
export class WriteComponent implements OnInit, OnDestroy, AfterViewInit {
  @ViewChild('editor', { static: true })
  editor: ElementRef<HTMLDivElement>;

  @ViewChild('fileInput', { static: true })
  fileInput: ElementRef<HTMLInputElement>;

  messageWriteForm: FormGroup;
  receiverList: string[] = ['이진호', '강희경', '이유진'];
  attachmentList: File[];

  constructor(
    private formBuilder: FormBuilder,
    private changeDetectorRef: ChangeDetectorRef,
    private logger: NGXLogger
  ) {}

  ngOnInit() {
    this.messageWriteForm = this.formBuilder.group({
      receiverList: ['', [Validators.required]],
      title: ['', [Validators.required]]
    });
  }

  ngOnDestroy(): void {}

  ngAfterViewInit(): void {}

  onClickImage() {
    this.fileInput.nativeElement.click();
    const self = this;
    this.fileInput.nativeElement.onchange = async () => {
      const fileList: FileList = self.fileInput.nativeElement.files;

      for (let i = 0; i < fileList.length; i++) {
        const file = fileList.item(i);

        const dataUrl = await FileUtil.fromBlobToDataUrl(file);
        const img = document.createElement('img');
        img.src = dataUrl as string;
        self.insertNode(img);
      }

      self.fileInput.nativeElement.value = '';
    };
  }

  onClickAttachment() {
    this.fileInput.nativeElement.click();
    const self = this;
    this.fileInput.nativeElement.onchange = () => {
      const fileList: FileList = this.fileInput.nativeElement.files;

      if (!self.attachmentList) {
        self.attachmentList = [];
      }

      for (let i = 0; i < fileList.length; i++) {
        const file = fileList.item(i);
        self.attachmentList.push(file);
      }

      self.changeDetectorRef.detectChanges();

      self.fileInput.nativeElement.value = '';
    };
  }

  onPasteEditor(event: ClipboardEvent) {
    const text = document.createTextNode(
      event.clipboardData.getData('text/plain')
    );
    this.insertNode(text, true);

    return false;
  }

  onClickSend() {}
  onClickCancel() {}

  printEditor(): void {
    const contentList: Content[] = [];

    this.editor.nativeElement.childNodes.forEach((v, k) => {
      this.parseNode(contentList, v);
    });

    this.logger.debug('printEditor', contentList);
  }

  private parseNode(contentList: Content[], node: ChildNode) {
    switch (node.nodeType) {
      case Node.ELEMENT_NODE:
        {
          if (0 < node.childNodes.length) {
            let prevNode: ChildNode;
            node.childNodes.forEach(v => {
              if (
                !!prevNode &&
                'IMG' === prevNode.nodeName &&
                'BR' === v.nodeName
              ) {
                prevNode = v;
                return;
              }
              prevNode = v;
              this.parseNode(contentList, v);
            });
          } else {
            if ('IMG' === node.nodeName) {
              this.appendNode(contentList, 'image', node.textContent);
            } else if ('BR' === node.nodeName) {
              this.appendNode(contentList, 'text', `\n`);
            } else {
            }
          }
        }
        break;
      case Node.TEXT_NODE:
        this.appendNode(contentList, 'text', node.textContent);
        break;

      default:
        break;
    }
  }

  private appendNode(
    contentList: Content[],
    contentType: 'text' | 'image' | 'attachment',
    content: string
  ) {
    const prevContent = contentList[contentList.length - 1];
    switch (contentType) {
      case 'text':
        if (!!prevContent && 'text' === prevContent.contentType) {
          prevContent.content = `${prevContent.content}${content}`;
        } else {
          contentList.push({
            contentType: 'text',
            content
          });
        }
        break;
      default:
        contentList.push({ contentType, content });
        break;
    }
  }

  private insertNode(node: Node, removeSelected: boolean = false) {
    const selection: Selection = document.getSelection();
    const range: Range = selection.getRangeAt(0);

    if (removeSelected) {
      selection.empty();
    }

    range.insertNode(node);
  }
}