Refactor print preview web ui

chrome/browser/resources/print_preview/data/ticket_items/custom_margins.js

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+cr.define('print_preview.ticket_items', function() {
+  'use strict';
+
+  /**
+   * Custom page margins ticket item whose value is a
+   * {@code print_preview.ticket_items.StringMargins}. The margin values need to
+   * be represented by a string since the user can textually input the values.
+   * @param {!print_preview.DocumentInfo} documentInfo Information about the
+   *     document to print.
+   * @param {!print_preview.MeasurementSystem} measurementSystem Used to convert
+   *     from string input into measurements in points.
+   * @constructor
+   * @extends {print_preview.ticket_items.TicketItem}
+   */
+  function CustomMargins(documentInfo, measurementSystem) {
+    print_preview.ticket_items.TicketItem.call(this);
+
+    /**
+     * Information about the document to print.
+     * @type {!print_preview.DocumentInfo}
+     * @private
+     */
+    this.documentInfo_ = documentInfo;
+
+    /**
+     * Used to convert from string input to measurements in points.
+     * @type {!print_preview.MeasurementSystem}
+     * @private
+     */
+    this.measurementSystem_ = measurementSystem;
+
+    /**
+     * Default value of the ticket item in points.
+     * @type {!print_preview.Margins}
+     * @private
+     */
+    this.defaultValueInPts_ = new print_preview.Margins(72, 72, 72, 72);
+
+    /**
+     * Cache of the the ticket item's value in points.
+     * @type {print_preview.Margins}
+     * @private
+     */
+    this.valueInPts_ = null;
+  };
+
+  /**
+   * Enumeration of the orientations of margins.
+   * @enum {string}
+   */
+  CustomMargins.Orientation = {
+    TOP: 'top',
+    RIGHT: 'right',
+    BOTTOM: 'bottom',
+    LEFT: 'left'
+  };
+
+  /**
+   * Precision used to convert from number in points to string in local units.
+   * @type {number}
+   * @const
+   * @private
+   */
+  CustomMargins.PRECISION_ = 3;
+
+  /**
+   * Minimum distance in points two margins can be separated by.
+   * @type {number}
+   * @const
+   * @private
+   */
+  CustomMargins.MINIMUM_MARGINS_DISTANCE_ = 72; // 1 inch.
+
+  CustomMargins.prototype = {
+    __proto__: print_preview.ticket_items.TicketItem.prototype,
+
+    /** @override */
+    wouldValueBeValid: function(value) {
+      var stringMargins =
+          /** @type {!print_preview.ticket_items.StringMargins} */ (value);
+      var marginsInPts = this.parseStringMarginsToPts_(stringMargins);
+      if (marginsInPts == null) {
+        return false;
+      }
+      for (var key in CustomMargins.Orientation) {
+        var o = CustomMargins.Orientation[key];
+        var max = this.getMarginMaxInPts_(o, marginsInPts.getOpposite(o));
+        max = this.measurementSystem_.convertFromPoints(max, true);
+        var margin =
+            this.measurementSystem_.convertFromPoints(marginsInPts.get(o));
+        if (margin > max || margin < 0) {
+          return false;
+        }
+      }
+      return true;
+    },
+
+    /** @override */
+    isCapabilityAvailable: function() {
+      return this.documentInfo_.isModifiable;
+    },
+
+    /**
+     * @param {print_preview.ticket_items.CustomMargins.Orientation} orientation
+     *     Specifies which margin to check if parseable.
+     * @return {boolean} Whether the specified margin is parseable.
+     */
+    isMarginParseable: function(orientation) {
+      return this.parseToPts_(this.getValue().get(orientation)) != null;
+    },
+
+    /**
+     * @return {!print_preview.Margins} The ticket items custom margins in
+     *     points.
+     */
+    getValueInPts: function() {
+      if (this.valueInPts_ == null) {
+        var stringMargins =
+            /** @type {!print_preview.ticket_items.StringMargins} */ (
+                this.getValue());
+        this.valueInPts_ = this.parseStringMarginsToPts_(stringMargins);
+        if (this.valueInPts_ == null) {
+          throw Error('Error while parsing margin values into points');
+        }
+      }
+      return this.valueInPts_;
+    },
+
+    /**
+     * @param {print_preview.ticket_items.CustomMargins.Orientation} orientation
+     *     Specifies the margin to get the maximum value for.
+     * @return {number} Maximum value in points of the specified margin.
+     */
+    getMarginMaxInPts: function(orientation) {
+      var marginsInPts = this.getValueInPts();
+      return this.getMarginMaxInPts_(
+          orientation, marginsInPts.getOpposite(orientation));
+    },
+
+    /** @override */
+    updateValue: function(value) {
+      print_preview.ticket_items.TicketItem.prototype.updateValue.call(
+          this, value);
+      this.valueInPts_ = null;
+    },
+
+    /**
+     * Updates the value of the ticket item with the given margins in points.
+     * @param {!print_preview.Margins} valueInPts Updated margins in points.
+     */
+    updateValueInPts: function(valueInPts) {
+      var o = CustomMargins.Orientation;
+      this.updateValue(new StringMargins(
+          this.serializeMarginFromPts(valueInPts.get(o.TOP)),
+          this.serializeMarginFromPts(valueInPts.get(o.RIGHT)),
+          this.serializeMarginFromPts(valueInPts.get(o.BOTTOM)),
+          this.serializeMarginFromPts(valueInPts.get(o.LEFT))));
+      this.valueInPts_ = valueInPts;
+    },
+
+    /**
+     * Updates the specified margin with a value in points.
+     * @param {print_preview.ticket_items.CustomMargins.Orientation} orientation
+     *     Specifies the margin to update.
+     * @param {number} valueInPts Updated margin in points.
+     */
+    updateMarginInPts: function(orientation, valueInPts) {
+      this.updateMargin(orientation, this.serializeMarginFromPts(valueInPts));
+    },
+
+    /**
+     * Updates the specified margin with the given string input.
+     * @param {print_preview.ticket_items.CustomMargins.Orientation} orientation
+     *     Specifies the margin to update.
+     * @param {string} value Updated string value of the margin.
+     */
+    updateMargin: function(orientation, value) {
+      var stringMargins =
+          /** @type {!print_preview.ticket_items.StringMargins} */ (
+              this.getValue());
+      var newStringMargins = stringMargins.set(orientation, value);
+      var newMarginsInPts = this.parseStringMarginsToPts_(newStringMargins);
+      if (newMarginsInPts != null) {
+        // Put updated margin within the valid range (between min and max).
+        var max = this.getMarginMaxInPts_(
+            orientation, newMarginsInPts.getOpposite(orientation));
+        max = this.measurementSystem_.convertFromPoints(max);
+        var newValue = this.measurementSystem_.convertFromPoints(
+            newMarginsInPts.get(orientation));
+        newValue = Math.max(0, Math.min(max, newValue));
+        this.updateValueInPts(newMarginsInPts.set(
+            orientation, this.measurementSystem_.convertToPoints(newValue)));
+      } else {
+        this.updateValue(newStringMargins);
+      }
+    },
+
+    /**
+     * Updates the default value of the margins ticket item. This value is used
+     * if the ticket item has not been edited by the user.
+     * @param {!print_preview.Margins} valueInPts Updated margin default values.
+     */
+    updateDefaultValueInPts: function(valueInPts) {
+      this.defaultValueInPts_ = valueInPts;
+      this.valueInPts_ = null;
+    },
+
+    /**
+     * @param {number} marginInPts Value of in points to serialize to a locale
+     *     string.
+     * @return {string} Serialized form of the given value in points. The
+     *     serialized value is in the user's local measurement system.
+     */
+    serializeMarginFromPts: function(marginInPts) {
+      return this.measurementSystem_.convertFromPoints(marginInPts) +
+          this.measurementSystem_.unitSymbol;
+    },
+
+    /** @override */
+    getDefaultValueInternal: function() {
+      return new StringMargins(
+          this.serializeMarginFromPts(
+              this.defaultValueInPts_.get(CustomMargins.Orientation.TOP)),
+          this.serializeMarginFromPts(
+              this.defaultValueInPts_.get(CustomMargins.Orientation.RIGHT)),
+          this.serializeMarginFromPts(
+              this.defaultValueInPts_.get(CustomMargins.Orientation.BOTTOM)),
+          this.serializeMarginFromPts(
+              this.defaultValueInPts_.get(CustomMargins.Orientation.LEFT)));
+    },
+
+    /** @override */
+    getCapabilityNotAvailableValueInternal: function() {
+      return this.getDefaultValueInternal();
+    },
+
+    /**
+     * @param {print_preview.ticket_items.CustomMargins.Orientation} orientation
+     *     Specifies which margin to get the maximum value of.
+     * @param {number} oppositeMarginInPts Value of the margin in points
+     *     opposite the specified margin.
+     * @return {number} Maximum value in points of the specified margin.
+     * @private
+     */
+    getMarginMaxInPts_: function(orientation, oppositeMarginInPts) {
+      if (orientation == CustomMargins.Orientation.TOP ||
+          orientation == CustomMargins.Orientation.BOTTOM) {
+        return this.documentInfo_.pageSize.height - oppositeMarginInPts -
+            CustomMargins.MINIMUM_MARGINS_DISTANCE_;
+      } else {
+        return this.documentInfo_.pageSize.width - oppositeMarginInPts -
+            CustomMargins.MINIMUM_MARGINS_DISTANCE_;
+      }
+    },
+
+    /**
+     * Parses the size of a margin in points from the given string.
+     * Example: "1.00", "1", ".5", "1.1" are valid values.
+     * Example: "1.4dsf", "-1" are invalid.
+     * Note: The inch symbol (") at the end of |text| is allowed.
+     * @param {string} text The text to parse.
+     * @param {print_preview.MeasurementSystem} measurementSystem Used to handle
+     *     parsing local units.
+     * @return {?number} The margin value represented by |text| in points or
+     *     {@code null} if |text| does not represent a valid value.
+     * @private
+     */
+    parseToPts_: function(text) {
+      // Removing whitespace anywhere in the string.
+      text = text.replace(/\s*/g, '');
+      if (text.length == 0) {
+        return null;
+      }
+      var validationRegex = new RegExp('^(^-?)(\\d)+(\\' +
+          this.measurementSystem_.thousandsDelimeter + '\\d{3})*(\\' +
+          this.measurementSystem_.decimalDelimeter + '\\d*)?' +
+          '(' + this.measurementSystem_.unitSymbol + ')?$');
+      if (validationRegex.test(text)) {
+        // Replacing decimal point with the dot symbol in order to use
+        // parseFloat() properly.
+        var replacementRegex =
+            new RegExp('\\' + this.measurementSystem_.decimalDelimeter + '{1}');
+        text = text.replace(replacementRegex, '.');
+        return this.measurementSystem_.convertToPoints(parseFloat(text));
+      }
+      return null;
+    },
+
+    /**
+     * Parses the given string margins into margins in points.
+     * @param {!print_preview.ticket_items.StringMargins} stringMargins String
+     *     margins to parse.
+     * @return {print_preview.Margins} The parsed margins in points, or
+     *     {@code null} if the string margins could not be parsed.
+     * @private
+     */
+    parseStringMarginsToPts_: function(stringMargins) {
+      var topInPts =
+          this.parseToPts_(stringMargins.get(CustomMargins.Orientation.TOP));
+      var rightInPts =
+          this.parseToPts_(stringMargins.get(CustomMargins.Orientation.RIGHT));
+      var bottomInPts =
+          this.parseToPts_(stringMargins.get(CustomMargins.Orientation.BOTTOM));
+      var leftInPts =
+          this.parseToPts_(stringMargins.get(CustomMargins.Orientation.LEFT));
+      if (topInPts == null ||
+          rightInPts == null ||
+          bottomInPts == null ||
+          leftInPts == null) {
+        return null;
+      }
+      return new print_preview.Margins(
+          topInPts, rightInPts, bottomInPts, leftInPts);
+    }
+  };
+
+  /**
+   * An immutable object that represents page margins as strings of values in
+   * the system's local measurement system.
+   * @param {string} top Top margin expressed as a string in the local
+   *     measurement system.
+   * @param {string} right Right margin expressed as a string in the local
+   *     measurement system.
+   * @param {string} bottom Bottom margin expressed as a string in the local
+   *     measurement system.
+   * @param {string} left Left margin expressed as a string in the local
+   *     measurement system.
+   * @constructor
+   */
+  function StringMargins(top, right, bottom, left) {
+    /**
+     * Backing store for the margin values.
+     * @type {Object.<
+     *     print_preview.ticket_items.CustomMargins.Orientation,
+     *     string>}
+     * @private
+     */
+    this.value_ = {};
+    this.value_[print_preview.ticket_items.CustomMargins.Orientation.TOP] = top;
+    this.value_[print_preview.ticket_items.CustomMargins.Orientation.RIGHT] =
+        right;
+    this.value_[print_preview.ticket_items.CustomMargins.Orientation.BOTTOM] =
+        bottom;
+    this.value_[print_preview.ticket_items.CustomMargins.Orientation.LEFT] =
+        left;
+  };
+
+  StringMargins.prototype = {
+    /**
+     * @param {print_preview.ticket_items.CustomMargins.Orientation} orientation
+     *     Specifies which margin value to get.
+     * @return {string} The value of the specified margin.
+     */
+    get: function(orientation) {
+      return this.value_[orientation];
+    },
+
+    /**
+     * @param {print_preview.ticket_items.CustomMargins.Orientation} orientation
+     *     Specifies the margin to modify.
+     * @param {string} value Updated value of the margin to modify.
+     * @return {!print_preview.ticket_items.StringMargins} A new copy of |this|
+     *     with the modification made to the specified margin.
+     */
+    set: function(orientation, value) {
+      var newValue = {};
+      for (var o in this.value_) {
+        newValue[o] = this.value_[o];
+      }
+      newValue[orientation] = value;
+      return new StringMargins(
+          newValue[print_preview.ticket_items.CustomMargins.Orientation.TOP],
+          newValue[print_preview.ticket_items.CustomMargins.Orientation.RIGHT],
+          newValue[print_preview.ticket_items.CustomMargins.Orientation.BOTTOM],
+          newValue[print_preview.ticket_items.CustomMargins.Orientation.LEFT]);
+    }
+  };
+
+  // Export
+  return {
+    CustomMargins: CustomMargins,
+    StringMargins: StringMargins
+  };
+});