/* Workspace interactions.
 *
 * Run and Submit are ordinary form submissions to /problems/<slug>/judge, so
 * the workspace works with scripting disabled. This file adds the editor
 * affordances the captured pane shows: line numbers, the Ln/Col readout, tab
 * insertion, the language switch, the case tabs, the console tabs and the
 * stopwatch. No guest code is ever executed here or on the server. */
(function () {
  "use strict";

  var editor = document.querySelector("[data-editor]");
  var gutter = document.querySelector("[data-gutter]");
  var cursor = document.querySelector("[data-cursor]");
  var saved = document.querySelector("[data-saved-state]");

  function lineCount(value) {
    return value.split("\n").length;
  }

  function paintGutter() {
    if (!gutter || !editor) {
      return;
    }
    var total = lineCount(editor.value);
    var numbers = [];
    for (var index = 1; index <= total; index += 1) {
      numbers.push(index);
    }
    gutter.textContent = numbers.join("\n");
  }

  function paintCursor() {
    if (!cursor || !editor) {
      return;
    }
    var upto = editor.value.slice(0, editor.selectionStart);
    var lines = upto.split("\n");
    cursor.textContent =
      "Ln " + lines.length + ", Col " + (lines[lines.length - 1].length + 1);
  }

  if (editor) {
    paintGutter();
    paintCursor();
    editor.addEventListener("input", function () {
      paintGutter();
      if (saved) {
        saved.textContent = "Unsaved";
      }
    });
    ["keyup", "click", "select"].forEach(function (name) {
      editor.addEventListener(name, paintCursor);
    });
    editor.addEventListener("scroll", function () {
      if (gutter) {
        gutter.style.transform = "translateY(" + -editor.scrollTop + "px)";
      }
    });
    editor.addEventListener("keydown", function (event) {
      if (event.key !== "Tab") {
        return;
      }
      event.preventDefault();
      var start = editor.selectionStart;
      var end = editor.selectionEnd;
      editor.value =
        editor.value.slice(0, start) + "    " + editor.value.slice(end);
      editor.selectionStart = editor.selectionEnd = start + 4;
      paintGutter();
      paintCursor();
    });
  }

  /* ---- language switch: reload with the chosen language -------------- */

  var language = document.querySelector("[data-language]");
  if (language) {
    language.addEventListener("change", function () {
      var url = new URL(window.location.href);
      url.searchParams.set("lang", language.value);
      window.location.href = url.pathname + url.search;
    });
  }

  /* ---- testcase tabs -------------------------------------------------- */

  var caseTabs = Array.prototype.slice.call(
    document.querySelectorAll("[data-case-tab]")
  );
  var casePanels = Array.prototype.slice.call(
    document.querySelectorAll("[data-case-panel]")
  );
  caseTabs.forEach(function (tab) {
    tab.addEventListener("click", function () {
      var wanted = tab.getAttribute("data-case-tab");
      caseTabs.forEach(function (other) {
        var active = other === tab;
        other.classList.toggle("is-active", active);
        other.setAttribute("aria-selected", active ? "true" : "false");
      });
      casePanels.forEach(function (panel) {
        panel.classList.toggle(
          "is-hidden",
          panel.getAttribute("data-case-panel") !== wanted
        );
      });
    });
  });

  /* ---- console tabs --------------------------------------------------- */

  var consoleTabs = Array.prototype.slice.call(
    document.querySelectorAll("[data-console-tab]")
  );
  var consolePanels = Array.prototype.slice.call(
    document.querySelectorAll("[data-console-panel]")
  );
  consoleTabs.forEach(function (tab) {
    tab.addEventListener("click", function () {
      var wanted = tab.getAttribute("data-console-tab");
      consoleTabs.forEach(function (other) {
        other.classList.toggle("is-active", other === tab);
      });
      consolePanels.forEach(function (panel) {
        panel.classList.toggle(
          "is-hidden",
          panel.getAttribute("data-console-panel") !== wanted
        );
      });
    });
  });

  /* ---- stopwatch ------------------------------------------------------ */

  var stopwatch = document.querySelector("[data-stopwatch]");
  if (stopwatch) {
    var elapsed = 0;
    var running = false;
    var pad = function (value) {
      return value < 10 ? "0" + value : String(value);
    };
    var paint = function () {
      stopwatch.textContent =
        pad(Math.floor(elapsed / 3600)) +
        ":" +
        pad(Math.floor((elapsed % 3600) / 60)) +
        ":" +
        pad(elapsed % 60);
    };
    stopwatch.setAttribute("role", "button");
    stopwatch.setAttribute("tabindex", "0");
    stopwatch.title = "Start or pause the stopwatch";
    stopwatch.addEventListener("click", function () {
      running = !running;
    });
    window.setInterval(function () {
      if (running) {
        elapsed += 1;
        paint();
      }
    }, 1000);
    paint();
  }
})();