obsidian-excalidraw-plugin/src/Prompt.ts

import { App, Modal } from "obsidian";

export class Prompt extends Modal {
  private promptEl: HTMLInputElement;
  private resolve: (value: string) => void;

  constructor(
    app: App,
    private prompt_text: string,
    private default_value: string,
    private placeholder: string,
    private prompt_desc?: string,
  ) {
    super(app);
  }

  onOpen(): void {
    this.titleEl.setText(this.prompt_text);
    this.createForm();
  }

  onClose(): void {
    this.contentEl.empty();
  }

  createForm(): void {
    let div = this.contentEl.createDiv();
    div.addClass("excalidraw-prompt-div");
    if (this.prompt_desc) {
      div = div.createDiv();
      div.style.width = "100%";
      const p = div.createEl("p");
      p.innerHTML = this.prompt_desc;
    }
    const form = div.createEl("form");
    form.addClass("excalidraw-prompt-form");
    form.type = "submit";
    form.onsubmit = (e: Event) => {
      e.preventDefault();
      this.resolve(this.promptEl.value);
      this.close();
    };

    this.promptEl = form.createEl("input");
    this.promptEl.type = "text";
    this.promptEl.placeholder = this.placeholder;
    this.promptEl.value = this.default_value ?? "";
    this.promptEl.addClass("excalidraw-prompt-input");
    this.promptEl.select();
  }

  async openAndGetValue(resolve: (value: string) => void): Promise<void> {
    this.resolve = resolve;
    this.open();
  }
}