cappuccino/AppKit/CPCompatibility.j

/*
 * CPCompatibility.j
 * AppKit
 *
 * Created by Francisco Tolmasky.
 * Copyright 2008, 280 North, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

@import "CPEvent_Constants.j"
@import "CPPlatform.j"


// Browser Engines
CPUnknownBrowserEngine                  = 0;
CPGeckoBrowserEngine                    = 1 << 0;
CPInternetExplorerBrowserEngine         = 1 << 1;
CPKHTMLBrowserEngine                    = 1 << 2;
CPOperaBrowserEngine                    = 1 << 3;
CPWebKitBrowserEngine                   = 1 << 4;  // Safari + Chrome
CPBlinkBrowserEngine                    = 1 << 5;  // Recent Chrome

// Operating Systems
CPMacOperatingSystem                    = 0;
CPWindowsOperatingSystem                = 1;
CPOtherOperatingSystem                  = 2;

// Features
CPCSSRGBAFeature                        = 5;

CPHTMLCanvasFeature                     = 6;
CPHTMLContentEditableFeature            = 7;
CPHTMLDragAndDropFeature                = 8;

CPJavaScriptInnerTextFeature            = 9;
CPJavaScriptTextContentFeature          = 10;
// In onpaste, oncopy and oncut events, the event has an event.clipboardData from which the current pasteboard contents can be read with event.clipboardData.getData.
CPJavaScriptClipboardEventsFeature      = 11;
// window.clipboardData exists and can be read and written to at any time using window.clipboardData.getData/setData.
CPJavaScriptClipboardAccessFeature      = 12;
CPJavaScriptCanvasDrawFeature           = 13;
CPJavaScriptCanvasTransformFeature      = 14;

CPVMLFeature                            = 15;

CPJavaScriptRemedialKeySupport          = 16;
CPJavaScriptShadowFeature               = 20;

CPJavaScriptNegativeMouseWheelValues    = 22;
CPJavaScriptMouseWheelValues_8_15       = 23;

CPOpacityRequiresFilterFeature          = 24;

// Internet explorer does not allow dynamically changing the type of an input element
CPInputTypeCanBeChangedFeature          = 25;
CPHTML5DragAndDropSourceYOffBy1         = 26;

CPSOPDisabledFromFileURLs               = 27;

// element.style.font can be set for an element not in the DOM.
CPInputSetFontOutsideOfDOM              = 28;

// Input elements have 1 px of extra padding on the left regardless of padding setting.
CPInput1PxLeftPadding                   = 29;
CPInputOnInputEventFeature              = 30;

CPFileAPIFeature                        = 31;

CPAltEnterTextAreaFeature               = 32;



/*
    When an absolutely positioned div (CPView) with an absolutely positioned canvas in it (CPView with drawRect:) moves things on top of the canvas (subviews) don't redraw correctly. E.g. if you have a bunch of text fields in a CPBox in a sheet which animates in, some of the text fields might not be visible because the CPBox has a canvas at the bottom and the box moved form offscreen to onscreen. This bug is probably very related: https://bugs.webkit.org/show_bug.cgi?id=67203
 */
CPCanvasParentDrawErrorsOnMovementBug   = 1 << 0;

// The paste event is only sent if an input or textarea has focus.
CPJavaScriptPasteRequiresEditableTarget = 1 << 1;
// Redirecting the focus of the browser on keydown to an input for Cmd-V or Ctrl-V makes the paste fail.
CPJavaScriptPasteCantRefocus            = 1 << 2;

/*
   Safari calculates incorrect text size unless you set the canvas font even if it is already set
       You can see the bug after disabling the workaround and opening any panel while typing.
       You can use the font panel in the manual test for CPTextView.
       Look out for a displaced cursor, i.e. after typing letters of small width, such as the 'i'.
       https://bugs.webkit.org/show_bug.cgi?id=150224
 */
CPTextSizingAlwaysNeedsSetFontBug       = 1 << 3;


var USER_AGENT                          = "",
    PLATFORM_ENGINE                     = CPUnknownBrowserEngine,
    PLATFORM_FEATURES                   = [],
    PLATFORM_BUGS                       = 0,
    PLATFORM_STYLE_JS_PROPERTIES        = {};

// default these features to true
PLATFORM_FEATURES[CPInputTypeCanBeChangedFeature] = YES;
PLATFORM_FEATURES[CPInputSetFontOutsideOfDOM] = YES;
PLATFORM_FEATURES[CPAltEnterTextAreaFeature] = YES;

if (typeof window !== "undefined" && typeof window.navigator !== "undefined")
    USER_AGENT = window.navigator.userAgent;

// Opera
if (typeof window !== "undefined" && window.opera)
{
    PLATFORM_ENGINE |= CPOperaBrowserEngine;

    PLATFORM_FEATURES[CPJavaScriptCanvasDrawFeature] = YES;
}

// Internet Explorer
else if (typeof window !== "undefined" && (window.attachEvent || (!(window.ActiveXObject) && "ActiveXObject" in window))) // Must follow Opera check.
{
    PLATFORM_ENGINE |= CPInternetExplorerBrowserEngine;

    // Features we can only be sure of with IE (no known independent tests)
    PLATFORM_FEATURES[CPVMLFeature] = YES;
    PLATFORM_FEATURES[CPJavaScriptRemedialKeySupport] = YES;
    PLATFORM_FEATURES[CPJavaScriptShadowFeature] = YES;

    PLATFORM_FEATURES[CPOpacityRequiresFilterFeature] = YES;

    PLATFORM_FEATURES[CPInputTypeCanBeChangedFeature] = NO;

    // Tested in Internet Explore 8 and 9.
    PLATFORM_FEATURES[CPInputSetFontOutsideOfDOM] = NO;

    // IE allows free clipboard access.
    PLATFORM_FEATURES[CPJavaScriptClipboardAccessFeature] = YES;
}

// Safari + Chrome (WebKit and Blink)
else if (USER_AGENT.indexOf("AppleWebKit/") != -1)
{
    PLATFORM_ENGINE |= CPWebKitBrowserEngine;

    // Features we can only be sure of with WebKit (no known independent tests)
    PLATFORM_FEATURES[CPCSSRGBAFeature] = YES;
    PLATFORM_FEATURES[CPHTMLContentEditableFeature] = YES;

    PLATFORM_FEATURES[CPJavaScriptClipboardEventsFeature] = YES;
    PLATFORM_FEATURES[CPJavaScriptClipboardAccessFeature] = NO;
    PLATFORM_FEATURES[CPJavaScriptShadowFeature] = YES;

    var versionStart = USER_AGENT.indexOf("AppleWebKit/") + "AppleWebKit/".length,
        versionEnd = USER_AGENT.indexOf(" ", versionStart),
        versionString = USER_AGENT.substring(versionStart, versionEnd),
        versionDivision = versionString.indexOf('.'),
        majorVersion = parseInt(versionString.substring(0, versionDivision)),
        minorVersion = parseInt(versionString.substr(versionDivision + 1));

    if ((USER_AGENT.indexOf("Safari") !== CPNotFound && (majorVersion > 525 || (majorVersion === 525 && minorVersion > 14))) || USER_AGENT.indexOf("Chrome") !== CPNotFound)
        PLATFORM_FEATURES[CPJavaScriptRemedialKeySupport] = YES;

    // FIXME this is a terrible hack to get around this bug:
    // https://bugs.webkit.org/show_bug.cgi?id=21548
    if (![CPPlatform isBrowser])
        PLATFORM_FEATURES[CPJavaScriptRemedialKeySupport] = YES;

    if (majorVersion < 532 || (majorVersion === 532 && minorVersion < 6))
        PLATFORM_FEATURES[CPHTML5DragAndDropSourceYOffBy1] = YES;

    // This is supposedly fixed in webkit r123603. Seems to work in Chrome 21 but not Safari 6.0.
    if (majorVersion < 537)
        PLATFORM_FEATURES[CPInput1PxLeftPadding] = YES;

    if (USER_AGENT.indexOf("Chrome") === CPNotFound)
    {
        PLATFORM_FEATURES[CPSOPDisabledFromFileURLs] = YES;
        PLATFORM_FEATURES[CPHTMLDragAndDropFeature] = YES;
        // https://bugs.webkit.org/show_bug.cgi?id=75891
        PLATFORM_BUGS |= CPJavaScriptPasteRequiresEditableTarget;
        // https://bugs.webkit.org/show_bug.cgi?id=39689
        PLATFORM_BUGS |= CPJavaScriptPasteCantRefocus;
        PLATFORM_BUGS |= CPTextSizingAlwaysNeedsSetFontBug;
    }
    else if ((window.chrome || (window.Intl && Intl.v8BreakIterator)) && 'CSS' in window)
        PLATFORM_ENGINE |= CPBlinkBrowserEngine;

    // Assume this bug was introduced around Safari 5.1/Chrome 16. This could probably be tighter.
    if (majorVersion > 533)
        PLATFORM_BUGS |= CPCanvasParentDrawErrorsOnMovementBug;
}

// KHTML
else if (USER_AGENT.indexOf("KHTML") != -1) // Must follow WebKit check.
{
    PLATFORM_ENGINE |= CPKHTMLBrowserEngine;
}

// Gecko
else if (USER_AGENT.indexOf("Gecko") !== -1) // Must follow KHTML check.
{
    PLATFORM_ENGINE |= CPGeckoBrowserEngine;

    PLATFORM_FEATURES[CPJavaScriptCanvasDrawFeature] = YES;

    var index = USER_AGENT.indexOf("Firefox"),
        version = (index === -1) ? 2.0 : parseFloat(USER_AGENT.substring(index + "Firefox".length + 1));

    if (version >= 3.0)
        PLATFORM_FEATURES[CPCSSRGBAFeature] = YES;

    if (version < 3.0)
        PLATFORM_FEATURES[CPJavaScriptMouseWheelValues_8_15] = YES;

    // Some day this might be fixed and should be version prefixed. No known fixed version yet.
    PLATFORM_FEATURES[CPInput1PxLeftPadding] = YES;

    PLATFORM_FEATURES[CPAltEnterTextAreaFeature] = NO;
    // This was supposed to be added in Firefox 22, but when testing with the latest beta as of 2013-06-14
    // it does not seem to work. It seems to exhibit the CPJavaScriptPasteRequiresEditableTarget problem,
    // and in addition doesn't seem to work with our native copy code either.
    /*if (version >= 22.0)
    {
        PLATFORM_FEATURES[CPJavaScriptClipboardEventsFeature] = YES;
        // TODO File a bug at https://bugzilla.mozilla.org/. In other browsers, one can return "false" from the
        // beforepaste event to indicate a paste should be enabled even that the DOMEvent.target is not editable.
        PLATFORM_BUGS |= CPJavaScriptPasteRequiresEditableTarget;
    }*/
}

// Feature-specific checks
if (typeof document != "undefined")
{
    var canvasElement = document.createElement("canvas");

    // Detect canvas support
    if (canvasElement && canvasElement.getContext)
    {
        PLATFORM_FEATURES[CPHTMLCanvasFeature] = YES;

        // Any browser that supports canvas supports CSS opacity
        PLATFORM_FEATURES[CPOpacityRequiresFilterFeature] = NO;

        // Detect canvas setTransform/transform support
        var context = document.createElement("canvas").getContext("2d");

        if (context && context.setTransform && context.transform)
            PLATFORM_FEATURES[CPJavaScriptCanvasTransformFeature] = YES;
    }

    var DOMElement = document.createElement("div");

    // Detect whether we have innerText or textContent (or neither)
    if (DOMElement.innerText != undefined)
        PLATFORM_FEATURES[CPJavaScriptInnerTextFeature] = YES;
    else if (DOMElement.textContent != undefined)
        PLATFORM_FEATURES[CPJavaScriptTextContentFeature] = YES;

    var DOMInputElement = document.createElement("input");

    if ("oninput" in DOMInputElement)
        PLATFORM_FEATURES[CPInputOnInputEventFeature] = YES;
    else if (typeof DOMInputElement.setAttribute === "function")
    {
        DOMInputElement.setAttribute("oninput", "return;");

        if (typeof DOMInputElement.oninput === "function")
            PLATFORM_FEATURES[CPInputOnInputEventFeature] = YES;
    }

    // Detect FileAPI support
    if (typeof DOMInputElement.setAttribute === "function")
    {
        DOMInputElement.setAttribute("type", "file");
        PLATFORM_FEATURES[CPFileAPIFeature] = !!DOMInputElement["files"];
    }
    else
        PLATFORM_FEATURES[CPFileAPIFeature] = NO;
}

function CPFeatureIsCompatible(aFeature)
{
    return !!PLATFORM_FEATURES[aFeature];
}

function CPPlatformHasBug(aBug)
{
    return PLATFORM_BUGS & aBug;
}

function CPBrowserIsEngine(anEngine)
{
    return PLATFORM_ENGINE & anEngine;
}

function CPBrowserIsOperatingSystem(anOperatingSystem)
{
    return OPERATING_SYSTEM === anOperatingSystem;
}

OPERATING_SYSTEM = CPOtherOperatingSystem;

if (USER_AGENT.indexOf("Mac") !== -1)
{
    OPERATING_SYSTEM = CPMacOperatingSystem;

    CPPlatformActionKeyMask = CPCommandKeyMask;

    CPUndoKeyEquivalent = @"z";
    CPRedoKeyEquivalent = @"Z";

    CPUndoKeyEquivalentModifierMask = CPCommandKeyMask;
    CPRedoKeyEquivalentModifierMask = CPCommandKeyMask;
}
else
{
    if (USER_AGENT.indexOf("Windows") !== -1)
        OPERATING_SYSTEM = CPWindowsOperatingSystem;

    CPPlatformActionKeyMask = CPControlKeyMask;

    CPUndoKeyEquivalent = @"z";
    CPRedoKeyEquivalent = @"y";

    CPUndoKeyEquivalentModifierMask = CPControlKeyMask;
    CPRedoKeyEquivalentModifierMask = CPControlKeyMask;
}

/*!
    Return the properly prefixed JS property for the given name. E.g. in a webkit browser,
    CPBrowserStyleProperty('transition') -> WebkitTransition

    While technically not a style property, style related event handler names are also supported.
    CPBrowserStyleProperty('transitionend') -> 'webkitTransitionEnd'

    CSS is only available in platform(dom), so don't rely too heavily on it.
*/
function CPBrowserStyleProperty(aProperty)
{
    var lowerProperty = aProperty.toLowerCase();

    if (PLATFORM_STYLE_JS_PROPERTIES[lowerProperty] === undefined)
    {
        var r = nil;

#if PLATFORM(DOM)
        var testElement = document.createElement('div');

        switch (lowerProperty)
        {
            case 'transitionend':
                var candidates = {
                        'WebkitTransition' : 'webkitTransitionEnd',
                        'MozTransition'    : 'transitionend',
                        'OTransition'      : 'oTransitionEnd',
                        'msTransition'     : 'MSTransitionEnd',
                        'transition'       : 'transitionend'
                    };

                r = candidates[PLATFORM_STYLE_JS_PROPERTIES['transition']] || nil;
                break;

            case 'transformorigin':

                var candidates = {
                        'WebkitTransform' : 'WebkitTransformOrigin',
                        'MozTransform'    : 'MozTransformOrigin',
                        'OTransform'      : 'OTransformOrigin',
                        'msTransform'     : 'MSTransformOrigin',
                        'transform'       : 'transformOrigin'
                    };

                r = candidates[PLATFORM_STYLE_JS_PROPERTIES['transform']] || nil;
                break;

            case 'animationend':
                var candidates = {
                        'WebkitAnimation' : 'webkitAnimationEnd',
                        'MozAnimation'    : 'animationend',
                        'OAnimation'      : 'oAnimationEnd',
                        'msAnimation'     : 'MSAnimationEnd',
                        'animation'       : 'animationend'
                    };

                r = candidates[PLATFORM_STYLE_JS_PROPERTIES['animation']] || nil;
                break;

            default:
                var prefixes = ["Webkit", "Moz", "O", "ms"],
                    strippedProperty = aProperty.split('-').join(' '),
                    capProperty = [strippedProperty capitalizedString].split(' ').join('');

                for (var i = 0; i < prefixes.length; i++)
                {
                    // First check if the property is already valid without being formatted, otherwise try the capitalized property
                    if (prefixes[i] + aProperty in testElement.style)
                    {
                        r = prefixes[i] + aProperty;
                        break;
                    }
                    else if (prefixes[i] + capProperty in testElement.style)
                    {
                        r = prefixes[i] + capProperty;
                        break;
                    }
                }

                if (!r && lowerProperty in testElement.style)
                    r = lowerProperty;

                break;
        }
#endif

        PLATFORM_STYLE_JS_PROPERTIES[lowerProperty] = r;
    }

    return PLATFORM_STYLE_JS_PROPERTIES[lowerProperty];
}

function CPBrowserCSSProperty(aProperty)
{
    var browserProperty = CPBrowserStyleProperty(aProperty);

    if (!browserProperty)
        return nil;

    var prefixes = {
            'Webkit': '-webkit-',
            'Moz': '-moz-',
            'O': '-o-',
            'ms': '-ms-'
        };

    for (var prefix in prefixes)
    {
        if (browserProperty.substring(0, prefix.length) == prefix)
        {
            var browserPropertyWithoutPrefix = browserProperty.substring(prefix.length),
                parts = browserPropertyWithoutPrefix.match(/[A-Z][a-z]+/g);

            // If there were any capitalized words in the browserProperty, insert a "-" between each one
            if (parts && parts.length > 0)
                browserPropertyWithoutPrefix = parts.join("-");

            return prefixes[prefix] + browserPropertyWithoutPrefix.toLowerCase();
        }
    }

    var parts = browserProperty.match(/[A-Z][a-z]+/g);

    if (parts && parts.length > 0)
        browserProperty = parts.join("-");

    return browserProperty.toLowerCase();
}

function CPBrowserBackingStorePixelRatio(context)
{
    return  context.webkitBackingStorePixelRatio ||
            context.mozBackingStorePixelRatio ||
            context.msBackingStorePixelRatio ||
            context.oBackingStorePixelRatio ||
            context.backingStorePixelRatio || 1;
}