jsPsych/packages/plugin-canvas-button-response/src/index.ts

import { JsPsych, JsPsychPlugin, ParameterType, TrialType } from "jspsych";

const info = <const>{
  name: "canvas-button-response",
  parameters: {
    /** The drawing function to apply to the canvas. Should take the canvas object as argument. */
    stimulus: {
      type: ParameterType.FUNCTION,
      pretty_name: "Stimulus",
      default: undefined,
    },
    /** Array containing the label(s) for the button(s). */
    choices: {
      type: ParameterType.STRING,
      pretty_name: "Choices",
      default: undefined,
      array: true,
    },
    /** The html of the button. Can create own style. */
    button_html: {
      type: ParameterType.HTML_STRING,
      pretty_name: "Button HTML",
      default: '<button class="jspsych-btn">%choice%</button>',
      array: true,
    },
    /** Any content here will be displayed under the button. */
    prompt: {
      type: ParameterType.HTML_STRING,
      pretty_name: "Prompt",
      default: null,
    },
    /** How long to hide the stimulus. */
    stimulus_duration: {
      type: ParameterType.INT,
      pretty_name: "Stimulus duration",
      default: null,
    },
    /** How long to show the trial. */
    trial_duration: {
      type: ParameterType.INT,
      pretty_name: "Trial duration",
      default: null,
    },
    /** The vertical margin of the button. */
    margin_vertical: {
      type: ParameterType.STRING,
      pretty_name: "Margin vertical",
      default: "0px",
    },
    /** The horizontal margin of the button. */
    margin_horizontal: {
      type: ParameterType.STRING,
      pretty_name: "Margin horizontal",
      default: "8px",
    },
    /** If true, then trial will end when user responds. */
    response_ends_trial: {
      type: ParameterType.BOOL,
      pretty_name: "Response ends trial",
      default: true,
    },
    /** Array containing the height (first value) and width (second value) of the canvas element. */
    canvas_size: {
      type: ParameterType.INT,
      array: true,
      pretty_name: "Canvas size",
      default: [500, 500],
    },
  },
};

type Info = typeof info;

/**
 * **canvas-button-response**
 *
 * jsPsych plugin for displaying a canvas stimulus and getting a button response
 *
 * @author Chris Jungerius (modified from Josh de Leeuw)
 * @see {@link https://www.jspsych.org/plugins/jspsych-canvas-button-response/ canvas-button-response plugin documentation on jspsych.org}
 */
class CanvasButtonResponsePlugin implements JsPsychPlugin<Info> {
  static info = info;

  constructor(private jsPsych: JsPsych) {}

  trial(display_element: HTMLElement, trial: TrialType<Info>) {
    // create canvas
    var html =
      '<div id="jspsych-canvas-button-response-stimulus">' +
      '<canvas id="jspsych-canvas-stimulus" height="' +
      trial.canvas_size[0] +
      '" width="' +
      trial.canvas_size[1] +
      '"></canvas>' +
      "</div>";

    //display buttons
    var buttons = [];
    if (Array.isArray(trial.button_html)) {
      if (trial.button_html.length == trial.choices.length) {
        buttons = trial.button_html;
      } else {
        console.error(
          "Error in canvas-button-response plugin. The length of the button_html array does not equal the length of the choices array"
        );
      }
    } else {
      for (var i = 0; i < trial.choices.length; i++) {
        buttons.push(trial.button_html);
      }
    }
    html += '<div id="jspsych-canvas-button-response-btngroup">';
    for (var i = 0; i < trial.choices.length; i++) {
      var str = buttons[i].replace(/%choice%/g, trial.choices[i]);
      html +=
        '<div class="jspsych-canvas-button-response-button" style="display: inline-block; margin:' +
        trial.margin_vertical +
        " " +
        trial.margin_horizontal +
        '" id="jspsych-canvas-button-response-button-' +
        i +
        '" data-choice="' +
        i +
        '">' +
        str +
        "</div>";
    }
    html += "</div>";

    //show prompt if there is one
    if (trial.prompt !== null) {
      html += trial.prompt;
    }
    display_element.innerHTML = html;

    //draw
    let c = document.getElementById("jspsych-canvas-stimulus");
    trial.stimulus(c);

    // start time
    var start_time = performance.now();

    // add event listeners to buttons
    for (var i = 0; i < trial.choices.length; i++) {
      display_element
        .querySelector<HTMLButtonElement>("#jspsych-canvas-button-response-button-" + i)
        .addEventListener("click", (e: MouseEvent) => {
          var btn_el = e.currentTarget as Element;
          var choice = btn_el.getAttribute("data-choice"); // don't use dataset for jsdom compatibility
          after_response(choice);
        });
    }

    // store response
    var response = {
      rt: null,
      button: null,
    };

    // function to end trial when it is time
    const end_trial = () => {
      // kill any remaining setTimeout handlers
      this.jsPsych.pluginAPI.clearAllTimeouts();

      // gather the data to store for the trial
      var trial_data = {
        rt: response.rt,
        response: response.button,
      };

      // clear the display
      display_element.innerHTML = "";

      // move on to the next trial
      this.jsPsych.finishTrial(trial_data);
    };

    // function to handle responses by the subject
    function after_response(choice) {
      // measure rt
      var end_time = performance.now();
      var rt = Math.round(end_time - start_time);
      response.button = parseInt(choice);
      response.rt = rt;

      // after a valid response, the stimulus will have the CSS class 'responded'
      // which can be used to provide visual feedback that a response was recorded
      display_element.querySelector("#jspsych-canvas-button-response-stimulus").className +=
        " responded";

      // disable all the buttons after a response
      var btns = document.querySelectorAll(".jspsych-canvas-button-response-button button");
      for (var i = 0; i < btns.length; i++) {
        //btns[i].removeEventListener('click');
        btns[i].setAttribute("disabled", "disabled");
      }

      if (trial.response_ends_trial) {
        end_trial();
      }
    }

    // hide image if timing is set
    if (trial.stimulus_duration !== null) {
      this.jsPsych.pluginAPI.setTimeout(() => {
        display_element.querySelector<HTMLElement>(
          "#jspsych-canvas-button-response-stimulus"
        ).style.visibility = "hidden";
      }, trial.stimulus_duration);
    }

    // end trial if time limit is set
    if (trial.trial_duration !== null) {
      this.jsPsych.pluginAPI.setTimeout(() => {
        end_trial();
      }, trial.trial_duration);
    }
  }

  simulate(
    trial: TrialType<Info>,
    simulation_mode,
    simulation_options: any,
    load_callback: () => void
  ) {
    if (simulation_mode == "data-only") {
      load_callback();
      this.simulate_data_only(trial, simulation_options);
    }
    if (simulation_mode == "visual") {
      this.simulate_visual(trial, simulation_options, load_callback);
    }
  }

  private create_simulation_data(trial: TrialType<Info>, simulation_options) {
    const default_data = {
      rt: this.jsPsych.randomization.sampleExGaussian(500, 50, 1 / 150, true),
      response: this.jsPsych.randomization.randomInt(0, trial.choices.length - 1),
    };

    const data = this.jsPsych.pluginAPI.mergeSimulationData(default_data, simulation_options);

    this.jsPsych.pluginAPI.ensureSimulationDataConsistency(trial, data);

    return data;
  }

  private simulate_data_only(trial: TrialType<Info>, simulation_options) {
    const data = this.create_simulation_data(trial, simulation_options);

    this.jsPsych.finishTrial(data);
  }

  private simulate_visual(trial: TrialType<Info>, simulation_options, load_callback: () => void) {
    const data = this.create_simulation_data(trial, simulation_options);

    const display_element = this.jsPsych.getDisplayElement();

    this.trial(display_element, trial);
    load_callback();

    if (data.rt !== null) {
      this.jsPsych.pluginAPI.clickTarget(
        display_element.querySelector(`div[data-choice="${data.response}"] button`),
        data.rt
      );
    }
  }
}

export default CanvasButtonResponsePlugin;