sharepulse/frontend/src/app/download/download.component.ts

import {Component, ElementRef, ViewChild} from '@angular/core';
import axios from "axios";
import {DevelopmentStore} from "../../store/DevelopmentStore";
import {FormsModule} from "@angular/forms";
import {DecimalPipe, NgClass, NgIf} from "@angular/common";
import funfacts from "../../assets/funfacts";
import {ActivatedRoute, RouterLink} from "@angular/router";

@Component({
  selector: 'app-download',
  standalone: true,
  imports: [
    FormsModule,
    NgIf,
    DecimalPipe,
    RouterLink,
    NgClass
  ],
  templateUrl: './download.component.html',
  styleUrl: './download.component.scss'
})
export class DownloadComponent {

  @ViewChild('download_not_possible') download_not_possible: ElementRef<HTMLDialogElement> | undefined;
  @ViewChild('file_not_found_modal') file_not_found_modal: ElementRef<HTMLDialogElement> | undefined;

  inputFileId: string = "";
  fileId: string = "";
  filePassword: string = "";
  fileName: string = "";
  downloadInfo: DownloadInfo | null = null;

  fileDownloadStarted: boolean = false;
  fileDownloadFinished: boolean = false;
  waitingForPassword: boolean = false;
  downloadProgress: number = 0;
  targetUploadProgress: number = 0;
  downloadDuration: string = "";
  passwordWrong: boolean = false;

  funfact: string = "";


  constructor(private developmentStore: DevelopmentStore, private activatedRoute: ActivatedRoute) {
    this.funfact = funfacts[Math.floor(Math.random() * funfacts.length)];

    this.activatedRoute.queryParams.subscribe(params => {
      const fileId = params['fileId'];
      const password = params['password'];
      if(password) {
        this.filePassword = password;
      }
      if(fileId) {
        this.inputFileId = fileId;
        this.requestDownload();
      }
    });

    this.speedTest();
  }

  requestDownload() {

    if(this.waitingForPassword) {
      console.log("Requesting download with password");
      this.downloadFile();
      return;
    }

    console.log(this.inputFileId);
    this.fileId = this.inputFileId; // TODO: Implement link extraction logic

    this.getDownloadInfo();
  }

  processDownloadInfo() {
    if(!this.downloadInfo?.passwordProtected && this.downloadInfo?.downloadable) {
      console.log("Proceeding with download");
      this.downloadFile();
      return;
    }
    else if(!this.downloadInfo?.downloadable) {
      this.download_not_possible?.nativeElement.showModal();
      return;
    }
    else if(this.downloadInfo?.passwordProtected) {
      if(this.filePassword) {
        console.log("Requesting download with password");
        this.downloadFile();
        return;
      }
      this.waitingForPassword = true;
      console.log("Password protected");
    }
  }

  private speedTest() {
    const start = new Date().getTime(); // Start timer

    axios({
      method: 'get',
      url: this.developmentStore.getBaseUrl() + 'api/v1/speed-test',
      responseType: 'arraybuffer',
    })
      .then(response => {
        const end = new Date().getTime(); // End timer
        const duration = (end - start) / 1000; // Convert ms to seconds
        const bitsLoaded = response.data.byteLength * 8;
        const speedBps = bitsLoaded / duration;
        const speedKbps = speedBps / 1024;
        const speedMbps = speedKbps / 1024;
        console.log(`Download speed: ${speedMbps.toFixed(2)} Mbps`);
      })
      .catch(error => {
        console.error('Error during download test:', error);
      });
  }

  private getDownloadInfo() {
    axios({
      method: 'get',
      url: this.developmentStore.getBaseUrl() + 'api/v1/download-info?fileId=' + this.fileId,
      responseType: 'json',
    })
    .then(response => {
      this.downloadInfo = response.data;
      console.log(response.data);
      this.processDownloadInfo();
    })
    .catch(error => {
      this.file_not_found_modal?.nativeElement.showModal();
      console.error('Error during download info request:', error);
    });
  }

  private downloadFile() {
    const startTime = new Date().getTime();
    this.fileDownloadStarted = true;
    axios({
      method: 'get',
      url: this.developmentStore.getBaseUrl() + 'api/v1/download?fileId=' + this.fileId + '&password=' + this.filePassword,
      responseType: 'arraybuffer',
      onDownloadProgress: (progressEvent) => {
        const endTime = new Date().getTime();
        const duration = (endTime - startTime) / 1000;
        this.downloadDuration = duration.toFixed(0);
        // Calculate the percentage of download completed
        if(progressEvent.total) {
          const percentCompleted = Math.round((progressEvent.loaded * 100) / progressEvent.total);
          this.targetUploadProgress = percentCompleted;
          this.smoothProgressUpdate();
        }
      }
    })
    .then(response => {
      const endTime = new Date().getTime();
      const duration = (endTime - startTime) / 1000;
      this.downloadDuration = duration.toFixed(2);
      this.fileDownloadFinished = true;

      const contentDisposition = response.headers['content-disposition'];
      let filename = "default_filename"; // Default filename in case parsing fails

      if (contentDisposition) {
        const filenameRegex = /filename="?([^"]+)"?/;
        const matches = contentDisposition.match(filenameRegex);
        if (matches && matches[1]) {
          filename = matches[1];
        }
      }
      this.fileName = filename;

      const blob = new Blob([response.data], {type: 'application/octet-stream'});
      const url = window.URL.createObjectURL(blob);
      const a = document.createElement('a');
      a.style.display = 'none';
      a.href = url;
      a.download = filename; // You can specify a filename here
      document.body.appendChild(a);
      a.click();

      // Clean up by revoking the Blob URL and removing the temporary anchor
      window.URL.revokeObjectURL(url);
      document.body.removeChild(a);
    })
    .catch(error => {
      this.fileDownloadStarted = false;
      this.wrongPassword();
      console.error('Error during download request:', error);
    });
  }

  private wrongPassword() {
    this.passwordWrong = true;
  }

  smoothProgressUpdate() {
    if (this.downloadProgress < this.targetUploadProgress) {
      this.downloadProgress += 0.01 * (this.targetUploadProgress - this.downloadProgress);
      requestAnimationFrame(this.smoothProgressUpdate.bind(this));
    } else if (this.downloadProgress > this.targetUploadProgress) {
      // Handle overshoot
      this.downloadProgress = this.targetUploadProgress;
    }
  }
}
interface DownloadInfo {
  downloadable: boolean;
  passwordProtected: boolean;
  singleDownload: boolean;
  fileId: string;
}