1 files changed, 465 insertions, 0 deletions
diff --git a/browser/components/urlbar/UrlbarProviderCalculator.sys.mjs b/browser/components/urlbar/UrlbarProviderCalculator.sys.mjs
new file mode 100644
index 0000000000..ae1216428b
--- /dev/null
+++ b/browser/components/urlbar/UrlbarProviderCalculator.sys.mjs
@@ -0,0 +1,465 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
+
+import {
+  UrlbarProvider,
+  UrlbarUtils,
+} from "resource:///modules/UrlbarUtils.sys.mjs";
+
+const lazy = {};
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  UrlbarPrefs: "resource:///modules/UrlbarPrefs.sys.mjs",
+  UrlbarResult: "resource:///modules/UrlbarResult.sys.mjs",
+  UrlbarView: "resource:///modules/UrlbarView.sys.mjs",
+});
+
+XPCOMUtils.defineLazyServiceGetter(
+  lazy,
+  "ClipboardHelper",
+  "@mozilla.org/widget/clipboardhelper;1",
+  "nsIClipboardHelper"
+);
+
+// This pref is relative to the `browser.urlbar` branch.
+const ENABLED_PREF = "suggest.calculator";
+
+const DYNAMIC_RESULT_TYPE = "calculator";
+
+const VIEW_TEMPLATE = {
+  attributes: {
+    selectable: true,
+  },
+  children: [
+    {
+      name: "content",
+      tag: "span",
+      attributes: { class: "urlbarView-no-wrap" },
+      children: [
+        {
+          name: "icon",
+          tag: "img",
+          attributes: { class: "urlbarView-favicon" },
+        },
+        {
+          name: "input",
+          tag: "strong",
+        },
+        {
+          name: "action",
+          tag: "span",
+        },
+      ],
+    },
+  ],
+};
+
+// Minimum number of parts of the expression before we show a result.
+const MIN_EXPRESSION_LENGTH = 3;
+
+/**
+ * A provider that returns a suggested url to the user based on what
+ * they have currently typed so they can navigate directly.
+ */
+class ProviderCalculator extends UrlbarProvider {
+  constructor() {
+    super();
+    lazy.UrlbarResult.addDynamicResultType(DYNAMIC_RESULT_TYPE);
+    lazy.UrlbarView.addDynamicViewTemplate(DYNAMIC_RESULT_TYPE, VIEW_TEMPLATE);
+  }
+
+  /**
+   * Returns the name of this provider.
+   *
+   * @returns {string} the name of this provider.
+   */
+  get name() {
+    return DYNAMIC_RESULT_TYPE;
+  }
+
+  /**
+   * The type of the provider.
+   *
+   * @returns {UrlbarUtils.PROVIDER_TYPE}
+   */
+  get type() {
+    return UrlbarUtils.PROVIDER_TYPE.PROFILE;
+  }
+
+  /**
+   * Whether this provider should be invoked for the given context.
+   * If this method returns false, the providers manager won't start a query
+   * with this provider, to save on resources.
+   *
+   * @param {UrlbarQueryContext} queryContext The query context object
+   * @returns {boolean} Whether this provider should be invoked for the search.
+   */
+  isActive(queryContext) {
+    return (
+      queryContext.trimmedSearchString &&
+      !queryContext.searchMode &&
+      lazy.UrlbarPrefs.get(ENABLED_PREF)
+    );
+  }
+
+  /**
+   * Starts querying. Extended classes should return a Promise resolved when the
+   * provider is done searching AND returning results.
+   *
+   * @param {UrlbarQueryContext} queryContext The query context object
+   * @param {Function} addCallback Callback invoked by the provider to add a new
+   *        result. A UrlbarResult should be passed to it.
+   */
+  async startQuery(queryContext, addCallback) {
+    try {
+      // Calculator will throw when given an invalid expression, therefore
+      // addCallback will never be called.
+      let postfix = Calculator.infix2postfix(queryContext.searchString);
+      if (postfix.length < MIN_EXPRESSION_LENGTH) {
+        return;
+      }
+      let value = Calculator.evaluatePostfix(postfix);
+      const result = new lazy.UrlbarResult(
+        UrlbarUtils.RESULT_TYPE.DYNAMIC,
+        UrlbarUtils.RESULT_SOURCE.OTHER_LOCAL,
+        {
+          value,
+          input: queryContext.searchString,
+          dynamicType: DYNAMIC_RESULT_TYPE,
+        }
+      );
+      result.suggestedIndex = 1;
+      addCallback(this, result);
+    } catch (e) {}
+  }
+
+  getViewUpdate(result) {
+    const viewUpdate = {
+      icon: {
+        attributes: {
+          src: "chrome://global/skin/icons/edit-copy.svg",
+        },
+      },
+      input: {
+        l10n: {
+          id: "urlbar-result-action-calculator-result",
+          args: { result: result.payload.value },
+        },
+      },
+      action: {
+        l10n: { id: "urlbar-result-action-copy-to-clipboard" },
+      },
+    };
+
+    return viewUpdate;
+  }
+
+  onEngagement(isPrivate, state, queryContext, details) {
+    let { result } = details;
+    if (result?.providerName == this.name) {
+      lazy.ClipboardHelper.copyString(result.payload.value);
+    }
+  }
+}
+
+/**
+ * Base implementation of a basic calculator.
+ */
+class BaseCalculator {
+  // Holds the current symbols for calculation
+  stack = [];
+  numberSystems = [];
+
+  addNumberSystem(system) {
+    this.numberSystems.push(system);
+  }
+
+  isNumeric(value) {
+    return value - 0 == value && value.length;
+  }
+
+  isOperator(value) {
+    return this.numberSystems.some(sys => sys.isOperator(value));
+  }
+
+  isNumericToken(char) {
+    return this.numberSystems.some(sys => sys.isNumericToken(char));
+  }
+
+  parsel10nFloat(num) {
+    for (const system of this.numberSystems) {
+      num = system.transformNumber(num);
+    }
+    return parseFloat(num, 10);
+  }
+
+  precedence(val) {
+    if (["-", "+"].includes(val)) {
+      return 2;
+    }
+    if (["*", "/"].includes(val)) {
+      return 3;
+    }
+
+    return null;
+  }
+
+  // This is a basic implementation of the shunting yard algorithm
+  // described http://en.wikipedia.org/wiki/Shunting-yard_algorithm
+  // Currently functions are unimplemented and only operators with
+  // left association are used
+  infix2postfix(infix) {
+    let parser = new Parser(infix, this);
+    let tokens = parser.parse(infix);
+    let output = [];
+    let stack = [];
+
+    tokens.forEach(token => {
+      if (token.number) {
+        output.push(this.parsel10nFloat(token.value, 10));
+      }
+
+      if (this.isOperator(token.value)) {
+        let i = this.precedence;
+        while (
+          stack.length &&
+          this.isOperator(stack[stack.length - 1]) &&
+          i(token.value) <= i(stack[stack.length - 1])
+        ) {
+          output.push(stack.pop());
+        }
+        stack.push(token.value);
+      }
+
+      if (token.value === "(") {
+        stack.push(token.value);
+      }
+
+      if (token.value === ")") {
+        while (stack.length && stack[stack.length - 1] !== "(") {
+          output.push(stack.pop());
+        }
+        // This is the (
+        stack.pop();
+      }
+    });
+
+    while (stack.length) {
+      output.push(stack.pop());
+    }
+    return output;
+  }
+
+  evaluate = {
+    "*": (a, b) => a * b,
+    "+": (a, b) => a + b,
+    "-": (a, b) => a - b,
+    "/": (a, b) => a / b,
+  };
+
+  evaluatePostfix(postfix) {
+    let stack = [];
+
+    postfix.forEach(token => {
+      if (!this.isOperator(token)) {
+        stack.push(token);
+      } else {
+        let op2 = stack.pop();
+        let op1 = stack.pop();
+        let result = this.evaluate[token](op1, op2);
+        if (isNaN(result)) {
+          throw new Error("Value is " + result);
+        }
+        stack.push(result);
+      }
+    });
+    let finalResult = stack.pop();
+    if (isNaN(finalResult)) {
+      throw new Error("Value is " + finalResult);
+    }
+    return finalResult;
+  }
+}
+
+function Parser(input, calculator) {
+  this.calculator = calculator;
+  this.init(input);
+}
+
+Parser.prototype = {
+  init(input) {
+    // No spaces.
+    input = input.replace(/[ \t\v\n]/g, "");
+
+    // String to array:
+    this._chars = [];
+    for (let i = 0; i < input.length; ++i) {
+      this._chars.push(input[i]);
+    }
+
+    this._tokens = [];
+  },
+
+  // This method returns an array of objects with these properties:
+  // - number: true/false
+  // - value:  the token value
+  parse(input) {
+    // The input must be a "block" without any digit left.
+    if (!this._tokenizeBlock() || this._chars.length) {
+      throw new Error("Wrong input");
+    }
+
+    return this._tokens;
+  },
+
+  _tokenizeBlock() {
+    if (!this._chars.length) {
+      return false;
+    }
+
+    // "(" + something + ")"
+    if (this._chars[0] == "(") {
+      this._tokens.push({ number: false, value: this._chars[0] });
+      this._chars.shift();
+
+      if (!this._tokenizeBlock()) {
+        return false;
+      }
+
+      if (!this._chars.length || this._chars[0] != ")") {
+        return false;
+      }
+
+      this._chars.shift();
+
+      this._tokens.push({ number: false, value: ")" });
+    } else if (!this._tokenizeNumber()) {
+      // number + ...
+      return false;
+    }
+
+    if (!this._chars.length || this._chars[0] == ")") {
+      return true;
+    }
+
+    while (this._chars.length && this._chars[0] != ")") {
+      if (!this._tokenizeOther()) {
+        return false;
+      }
+
+      if (!this._tokenizeBlock()) {
+        return false;
+      }
+    }
+
+    return true;
+  },
+
+  // This is a simple float parser.
+  _tokenizeNumber() {
+    if (!this._chars.length) {
+      return false;
+    }
+
+    // {+,-}something
+    let number = [];
+    if (/[+-]/.test(this._chars[0])) {
+      number.push(this._chars.shift());
+    }
+
+    let tokenizeNumberInternal = () => {
+      if (
+        !this._chars.length ||
+        !this.calculator.isNumericToken(this._chars[0])
+      ) {
+        return false;
+      }
+
+      while (
+        this._chars.length &&
+        this.calculator.isNumericToken(this._chars[0])
+      ) {
+        number.push(this._chars.shift());
+      }
+
+      return true;
+    };
+
+    if (!tokenizeNumberInternal()) {
+      return false;
+    }
+
+    // 123{e...}
+    if (!this._chars.length || this._chars[0] != "e") {
+      this._tokens.push({ number: true, value: number.join("") });
+      return true;
+    }
+
+    number.push(this._chars.shift());
+
+    // 123e{+,-}
+    if (/[+-]/.test(this._chars[0])) {
+      number.push(this._chars.shift());
+    }
+
+    if (!this._chars.length) {
+      return false;
+    }
+
+    // the number
+    if (!tokenizeNumberInternal()) {
+      return false;
+    }
+
+    this._tokens.push({ number: true, value: number.join("") });
+    return true;
+  },
+
+  _tokenizeOther() {
+    if (!this._chars.length) {
+      return false;
+    }
+
+    if (this.calculator.isOperator(this._chars[0])) {
+      this._tokens.push({ number: false, value: this._chars.shift() });
+      return true;
+    }
+
+    return false;
+  },
+};
+
+export let Calculator = new BaseCalculator();
+
+Calculator.addNumberSystem({
+  isOperator: char => ["÷", "×", "-", "+", "*", "/"].includes(char),
+  isNumericToken: char => /^[0-9\.,]/.test(char),
+  // parseFloat will only handle numbers that use periods as decimal
+  // seperators, various countries use commas. This function attempts
+  // to fixup the number so parseFloat will accept it.
+  transformNumber: num => {
+    let firstComma = num.indexOf(",");
+    let firstPeriod = num.indexOf(".");
+
+    if (firstPeriod != -1 && firstComma != -1 && firstPeriod < firstComma) {
+      // Contains both a period and a comma and the period came first
+      // so using comma as decimal seperator, strip . and replace , with .
+      // (ie 1.999,5).
+      num = num.replace(/\./g, "");
+      num = num.replace(/,/g, ".");
+    } else if (firstPeriod != -1 && firstComma != -1) {
+      // Contains both a period and a comma and the comma came first
+      // so strip the comma (ie 1,999.5).
+      num = num.replace(/,/g, "");
+    } else if (firstComma != -1) {
+      // Has commas but no periods so treat comma as decimal seperator
+      num = num.replace(/,/g, ".");
+    }
+    return num;
+  },
+});
+
+export var UrlbarProviderCalculator = new ProviderCalculator();