/*

    File:       HIDoubleSlider.cp

    Contains:   Demonstrates creating a double slider using the HIView APIs.

    Version:    1.0

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                PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND OPERATION ALONE OR IN

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    Copyright © 2002 Apple Computer, Inc., All Rights Reserved

*/

#include <Carbon/Carbon.h>

#include "HIDoubleSlider.h"

// structure in which we hold our custom push button's data

typedef struct

    {

    HIViewRef   view;                           // the HIViewRef for our button

    SInt32      hiValue;                        // our settings

    SInt32      loValue;

    ControlRef  invisibleHiSlider;

    ControlRef  invisibleLoSlider;

    }

DoubleSliderData;

pascal OSStatus ViewHandler(EventHandlerCallRef inCaller, EventRef inEvent, void* inRefcon);

CFStringRef GetDoubleSliderClass();

void SetControlHiLoValue(ControlRef theControl, SInt32 newValue, Boolean hiOrLo);

/*

 *  HICreateDoubleSlider()

 *  

 *  Summary:

 *    Creates a double slider control.

 *  

 *  Parameters:

 *    

 *    boundsRect:

 *      The bounding box of the control.

 *    

 *    minimum:

 *    maximum:

 *    loValue:

 *    hiValue:

 *      32 Bits settings.

 *    

 *    outDoubleSlider:

 *      On exit, contains the new control.

 *  

 *  Availability:

 *    Mac OS X:         in version 10.2 and later since it needs the HIView APIs

 *    CarbonLib:        not available

 *    Non-Carbon CFM:   not available

 */

OSStatus 

HICreateDoubleSlider(

  const HIRect *    boundsRect,

  SInt32 minimum, SInt32 maximum, SInt32 loValue, SInt32 hiValue,

  HIViewRef *       outDoubleSlider)

    {

    EventRef theInitializeEvent = NULL;

    HIObjectRef hiObject = NULL;

    OSStatus theStatus = CreateEvent(NULL, kEventClassHIObject, kEventHIObjectInitialize, GetCurrentEventTime(), kEventAttributeUserEvent, &theInitializeEvent);

    if (theStatus != noErr) goto exitCreation;

    // settings

    SetEventParameter(theInitializeEvent, kControlLoValueTag, typeSInt32, sizeof(loValue), &loValue);

    SetEventParameter(theInitializeEvent, kControlHiValueTag, typeSInt32, sizeof(hiValue), &hiValue);

    SetEventParameter(theInitializeEvent, kControlCollectionTagMinimum, typeSInt32, sizeof(minimum), &minimum);

    SetEventParameter(theInitializeEvent, kControlCollectionTagMaximum, typeSInt32, sizeof(maximum), &maximum);

    SetEventParameter(theInitializeEvent, kControlCollectionTagBounds, typeHIRect, sizeof(HIRect), boundsRect);

    theStatus = HIObjectCreate(GetDoubleSliderClass(), theInitializeEvent, &hiObject);

    if (theStatus != noErr) goto exitCreation;

exitCreation:

    *outDoubleSlider = (HIViewRef)hiObject;

    if (theInitializeEvent != NULL) ReleaseEvent(theInitializeEvent);

    return theStatus;

    }

UInt32 GetHIToolboxVersion()

    {

    CFBundleRef bundle;

    CFStringRef versionStr = NULL;

    static UInt32 version = 0;

    if (version != 0) return version;

    bundle = CFBundleGetBundleWithIdentifier( CFSTR("com.apple.HIToolbox") );

    if ( bundle != NULL )

        versionStr = (CFStringRef) CFBundleGetValueForInfoDictionaryKey( bundle, CFSTR("CFBundleShortVersionString") );

    if ( versionStr != NULL && CFGetTypeID( versionStr ) == CFStringGetTypeID() )

        {

        int major = 0, minor = 0, bugfix = 0;

        char sz[20];

        CFStringGetCString( versionStr, sz, sizeof( sz ), kCFStringEncodingUTF8 );

        sscanf( sz, "%d.%d.%d", &major, &minor, &bugfix );

        version = ( major << 8 ) + ( minor << 4 ) + bugfix;

        }

    return version;

    }

/*----------------------------------------------------------------------------------------------------------*/

//  ¥ GetDoubleSliderClass

//  Registers and returns an HIObject class for a double slider.

/*----------------------------------------------------------------------------------------------------------*/

CFStringRef GetDoubleSliderClass()

    {

    // following code is pretty much boiler plate.

    static HIObjectClassRef theClass;

    if (theClass == NULL)

        {

        static EventTypeSpec kFactoryEvents[] =

            {

                // the next 3 messages are boiler plate

                { kEventClassHIObject, kEventHIObjectConstruct },

                { kEventClassHIObject, kEventHIObjectInitialize },

                { kEventClassHIObject, kEventHIObjectDestruct },

                // the next 2 messages are specific to our class

                { kEventClassDoubleSlider, kEventControlHiValueFieldChanged },

                { kEventClassDoubleSlider, kEventControlLoValueFieldChanged },

                // the next messages are the minimum messages we need to

                // implement the double slider control.

                { kEventClassControl, kEventControlInitialize },

                { kEventClassControl, kEventControlHitTest },

                { kEventClassControl, kEventControlTrack },

                { kEventClassControl, kEventControlHiliteChanged },

                { kEventClassControl, kEventControlActivate },

                { kEventClassControl, kEventControlDeactivate },

                { kEventClassControl, kEventControlDraw }

            };

        HIObjectRegisterSubclass(kDoubleSliderClassID, kHIViewClassID, 0, ViewHandler,

                                  GetEventTypeCount(kFactoryEvents), kFactoryEvents, 0, &theClass);

        }

    return kDoubleSliderClassID;

    }

/*----------------------------------------------------------------------------------------------------------*/

//  ¥ GetLoHiRects

//  returns the Rects of both our indicators.

/*----------------------------------------------------------------------------------------------------------*/

void GetLoHiRects(DoubleSliderData* myData, Rect *loRect, Rect *hiRect)

    {

    SetControl32BitValue(myData->invisibleLoSlider, myData->loValue);

    SetControl32BitValue(myData->invisibleHiSlider, myData->hiValue);

    RgnHandle theRgn = NewRgn();

    GetControlRegion(myData->invisibleLoSlider, kControlIndicatorPart, theRgn);

    GetRegionBounds(theRgn, loRect);

    GetControlRegion(myData->invisibleHiSlider, kControlIndicatorPart, theRgn);

    GetRegionBounds(theRgn, hiRect);

    DisposeRgn(theRgn);

    }

enum

    {

    kControlHiIndicatorPart = 170,

    kControlLoIndicatorPart = 171

    };

/*----------------------------------------------------------------------------------------------------------*/

//  ¥ FindPart

//  returns which part the Point (from the EventRef) is in or kControlNoPart if not.

/*----------------------------------------------------------------------------------------------------------*/

ControlPartCode FindPart(EventRef inEvent, DoubleSliderData* myData)

    {

    ControlPartCode part = kControlNoPart;

    // the point parameter is in view-local coords.

    Point qdPoint;

    GetEventParameter(inEvent, kEventParamMouseLocation, typeQDPoint, NULL, sizeof(qdPoint), NULL, &qdPoint);

    Rect loRect, hiRect;

    GetLoHiRects(myData, &loRect, &hiRect);

    if (PtInRect(qdPoint, &loRect)) part = kControlLoIndicatorPart;

    if (PtInRect(qdPoint, &hiRect)) part = kControlHiIndicatorPart;

        // if both values are at the maximum, we need to return the Lo indicator part or nothing will move ever again!

        if (myData->loValue == myData->hiValue)

            {

            SInt32 max = GetControl32BitMaximum(myData->view);

            if (max == myData->loValue)

                part = kControlLoIndicatorPart;

            }

    return part;

    }

/*----------------------------------------------------------------------------------------------------------*/

//  ¥ DrawSlider

//  Draws the bar and both indicators using ONLY Appearance calls.

/*----------------------------------------------------------------------------------------------------------*/

void DrawSliderJaguar(DoubleSliderData* myData)

    {

    ThemeTrackDrawInfo drawInfo;

    drawInfo.kind = kThemeSlider;

    HIRect hiBounds;

    HIViewGetBounds(myData->view, &hiBounds);

    drawInfo.bounds.left = drawInfo.bounds.top = 0;

    drawInfo.bounds.right = (int)hiBounds.size.width;

    drawInfo.bounds.bottom =  (int)hiBounds.size.height;

    drawInfo.min = GetControl32BitMinimum(myData->view);

    drawInfo.max = GetControl32BitMaximum(myData->view);

    drawInfo.enableState = (IsControlActive(myData->view) && IsControlEnabled(myData->view))?kThemeTrackActive:kThemeTrackInactive;

    drawInfo.trackInfo.slider.pressState = 0;

    drawInfo.attributes = kThemeTrackRightToLeft;

    drawInfo.trackInfo.slider.thumbDir = kThemeThumbPlain;

    DrawThemeTrack(&drawInfo, NULL, NULL, NULL);

    Rect loRect, hiRect;

    GetLoHiRects(myData, &loRect, &hiRect);

    drawInfo.attributes = kThemeTrackRightToLeft | kThemeTrackShowThumb;

    drawInfo.bounds.top = loRect.top + 2;

    drawInfo.bounds.bottom = drawInfo.bounds.top + 16;

    drawInfo.value = myData->loValue;

    drawInfo.trackInfo.slider.thumbDir = kThemeThumbUpward;

    if (IsControlHilited(myData->view))

        if (GetControlHilite(myData->view) == kControlLoIndicatorPart)

            drawInfo.trackInfo.slider.pressState = kThemeThumbPressed;

    DrawThemeTrack(&drawInfo, NULL, NULL, NULL);

    drawInfo.trackInfo.slider.pressState = 0;

    drawInfo.bounds.top = hiRect.top + 2;

    drawInfo.bounds.bottom = drawInfo.bounds.top + 16;

    drawInfo.value = myData->hiValue;

    drawInfo.trackInfo.slider.thumbDir = kThemeThumbDownward;

    if (IsControlHilited(myData->view))

        if (GetControlHilite(myData->view) == kControlHiIndicatorPart)

            drawInfo.trackInfo.slider.pressState = kThemeThumbPressed;

    DrawThemeTrack(&drawInfo, NULL, NULL, NULL);

    }

void DrawSliderPanther(DoubleSliderData* myData, CGContextRef context)

    {

    HIThemeTrackDrawInfo drawInfo;

    drawInfo.version = 0;

    drawInfo.kind = kThemeSlider;

    HIViewGetBounds(myData->view, &drawInfo.bounds);

    drawInfo.min = GetControl32BitMinimum(myData->view);

    drawInfo.max = GetControl32BitMaximum(myData->view);

    drawInfo.enableState = (IsControlActive(myData->view) && IsControlEnabled(myData->view))?kThemeTrackActive:kThemeTrackInactive;

    drawInfo.trackInfo.slider.pressState = 0;

    drawInfo.attributes = kThemeTrackRightToLeft;

    drawInfo.trackInfo.slider.thumbDir = kThemeThumbPlain;

    HIThemeDrawTrack(&drawInfo, NULL, context, kHIThemeOrientationNormal);

    Rect loRect, hiRect;

    GetLoHiRects(myData, &loRect, &hiRect);

    drawInfo.attributes = kThemeTrackRightToLeft | kThemeTrackShowThumb;

    drawInfo.bounds.origin.y = loRect.top + 2;

    drawInfo.bounds.size.height = 16;

    drawInfo.value = myData->loValue;

    drawInfo.trackInfo.slider.thumbDir = kThemeThumbUpward;

    if (IsControlHilited(myData->view))

        if (GetControlHilite(myData->view) == kControlLoIndicatorPart)

            drawInfo.trackInfo.slider.pressState = kThemeThumbPressed;

    HIThemeDrawTrack(&drawInfo, NULL, context, kHIThemeOrientationNormal);

    drawInfo.trackInfo.slider.pressState = 0;

    drawInfo.bounds.origin.y = hiRect.top + 2;

//  drawInfo.bounds.bottom = drawInfo.bounds.top + 16;

    drawInfo.value = myData->hiValue;

    drawInfo.trackInfo.slider.thumbDir = kThemeThumbDownward;

    if (IsControlHilited(myData->view))

        if (GetControlHilite(myData->view) == kControlHiIndicatorPart)

            drawInfo.trackInfo.slider.pressState = kThemeThumbPressed;

    HIThemeDrawTrack(&drawInfo, NULL, context, kHIThemeOrientationNormal);

    }

/*----------------------------------------------------------------------------------------------------------*/

//  ¥ ViewHandler

//  Event handler that implements our double slider.

/*----------------------------------------------------------------------------------------------------------*/

pascal OSStatus ViewHandler(EventHandlerCallRef inCaller, EventRef inEvent, void* inRefcon)

    {

    OSStatus result = eventNotHandledErr;

    DoubleSliderData*   myData = (DoubleSliderData*)inRefcon;

    switch (GetEventClass(inEvent))

        {

        case kEventClassHIObject:

            switch (GetEventKind(inEvent))

                {

                case kEventHIObjectConstruct:

                    {

                    // allocate some instance data

                    myData = (DoubleSliderData*) calloc(1, sizeof(DoubleSliderData));

                    // get our superclass instance

                    HIViewRef epView;

                    GetEventParameter(inEvent, kEventParamHIObjectInstance, typeHIObjectRef, NULL, sizeof(epView), NULL, &epView);

                    // remember our superclass in our instance data and initialize other fields

                    myData->view = epView;

                    myData->invisibleHiSlider = NULL;

                    myData->invisibleLoSlider = NULL;

                    // store our instance data into the event

                    result = SetEventParameter(inEvent, kEventParamHIObjectInstance, typeVoidPtr, sizeof(myData), &myData);

                    break;

                    }

                case kEventHIObjectDestruct:

                    {

                    if (myData->invisibleLoSlider) DisposeControl(myData->invisibleLoSlider);

                    if (myData->invisibleHiSlider) DisposeControl(myData->invisibleHiSlider);

                    free(myData);

                    result = noErr;

                    break;

                    }

                case kEventHIObjectInitialize:

                    {

                    // always begin kEventHIObjectInitialize by calling through to the previous handler

                    result = CallNextEventHandler(inCaller, inEvent);

                    // if that succeeded, do our own initialization

                    if (result == noErr)

                        {

                        // settings

                        GetEventParameter(inEvent, kControlLoValueTag, typeSInt32, NULL, sizeof(myData->loValue), NULL, &myData->loValue);

                        GetEventParameter(inEvent, kControlHiValueTag, typeSInt32, NULL, sizeof(myData->hiValue), NULL, &myData->hiValue);

                        SInt32 minimum;

                        GetEventParameter(inEvent, kControlCollectionTagMinimum, typeSInt32, NULL, sizeof(minimum), NULL, &minimum);

                        SetControl32BitMinimum(myData->view, minimum);

                        SInt32 maximum;

                        GetEventParameter(inEvent, kControlCollectionTagMaximum, typeSInt32, NULL, sizeof(maximum), NULL, &maximum);

                        SetControl32BitMaximum(myData->view, maximum);

                        HIRect bounds;

                        GetEventParameter(inEvent, kControlCollectionTagBounds, typeHIRect, NULL, sizeof(bounds), NULL, &bounds);

                        HIViewSetFrame(myData->view, &bounds);

                        Rect cBounds = { 0, 0, (int)bounds.size.height - 1, (int)bounds.size.width };

                        // creating 2 invisible sliders to steal information from when needed.

                        CreateSliderControl(NULL, &cBounds, 0, minimum, maximum, kControlSliderPointsDownOrRight, 0, false, NULL, &myData->invisibleLoSlider);

                        CreateSliderControl(NULL, &cBounds, 0, minimum, maximum, kControlSliderPointsUpOrLeft, 0, false, NULL, &myData->invisibleHiSlider);

                        HIViewSetVisible(myData->invisibleLoSlider, false);

                        HIViewSetVisible(myData->invisibleHiSlider, false);

                        // we're embedding those invisible sliders in our own view so that they move along

                        HIViewAddSubview(myData->view, myData->invisibleLoSlider);

                        HIViewAddSubview(myData->view, myData->invisibleHiSlider);

                        }

                    break;

                    }

                default:

                    break;

                }

            break;

        case kEventClassDoubleSlider:

            switch (GetEventKind(inEvent))

                {

                case kEventControlHiValueFieldChanged:

                case kEventControlLoValueFieldChanged:

                    HIViewSetNeedsDisplay(myData->view, true);

                    result = noErr;

                    break;

                default:

                    break;

                }

            break;

        case kEventClassControl:

            switch (GetEventKind(inEvent))

                {

                case kEventControlInitialize:

                    {

                    CallNextEventHandler(inCaller, inEvent);

                    UInt32 features = 0;

                    result = GetEventParameter(inEvent, kEventParamControlFeatures, typeUInt32, NULL, sizeof(features), NULL, &features);

                    if (result == noErr)

                        features |= kControlSupportsEmbedding;

                    else

                        features = kControlSupportsEmbedding;

                    result = SetEventParameter(inEvent, kEventParamControlFeatures, typeUInt32, sizeof features, &features);

                    break;

                    }

#pragma mark -

#pragma mark case kEventControlDraw

                case kEventControlDraw:

                    {

                    static bool hiToolboxVersionTested = false;

                    static bool canUseHITheme = false;

                    if (! hiToolboxVersionTested)

                        {

                        hiToolboxVersionTested = true;

                        canUseHITheme = (GetHIToolboxVersion() >= 0x130);

                        }

                    CGContextRef context;

                    result = GetEventParameter(inEvent, kEventParamCGContextRef, typeCGContextRef, NULL, sizeof(context), NULL, &context);

                    if (canUseHITheme && (result == noErr) && (context != NULL))

                        DrawSliderPanther(myData, context);

                    else

                        DrawSliderJaguar(myData);

                    result = noErr;

                    break;

                    }

#pragma mark case kEventControlHitTest

                case kEventControlHitTest:

                    {

                    ControlPartCode part = FindPart(inEvent, myData);

                    SetEventParameter(inEvent, kEventParamControlPart, typeControlPartCode, sizeof(part), &part);

                    result = noErr;

                    break;

                    }

#pragma mark case kEventControlTrack

                case kEventControlTrack:

                    {

                    ControlPartCode part = FindPart(inEvent, myData);

                    // was part clicked hilited before? If not, hilite it.

                    if (part != GetControlHilite(myData->view))

                        HiliteControl(myData->view, part);

                    ControlRef theControl = NULL;

                    if (part == kControlHiIndicatorPart) theControl = myData->invisibleHiSlider;

                    if (part == kControlLoIndicatorPart) theControl = myData->invisibleLoSlider;

                    if (theControl == NULL) break;

                    Rect loRect, hiRect;

                    GetLoHiRects(myData, &loRect, &hiRect);

                    SInt32 height = hiRect.bottom - hiRect.top;

                    SInt32 min = GetControl32BitMinimum(theControl);

                    SInt32 max = GetControl32BitMaximum(theControl);

                    // we need the location of our invisible sliders in local coordinates of the window (actually the content view)

                    HIRect hiFrame;

                    HIViewGetFrame(theControl, &hiFrame);

                    HIViewRef contentView;

                    HIViewFindByID(HIViewGetRoot(GetControlOwner(myData->view)), kHIViewWindowContentID, &contentView);

                    HIViewConvertRect(&hiFrame, myData->view, contentView);

                    SInt32 fTop = (int)hiFrame.origin.y;

                    SInt32 fBottom = fTop + (int)hiFrame.size.height;

                    // determining (as best as can be done) the delta value which comes from the fact

                    // that we clicked in any point of the indicator, but the value associated with the indicator

                    // is for only one line within.

                    Point pt;

                    GetEventParameter(inEvent, kEventParamMouseLocation, typeQDPoint, NULL, sizeof(pt), NULL, &pt);

                    pt.v += fTop;

                    SInt32 deltaValue = min + ((fBottom - pt.v - (height / 2)) * (max - min)) / (fBottom - fTop - height);

                    SInt32 value = (part == kControlHiIndicatorPart)?myData->hiValue:myData->loValue;

                    deltaValue -= value;

                    // tracking (needs a QD Grafport. Actually it doesn't but it's simpler that way for managing local vs. global coords)

                    GrafPtr savePort;

                    GetPort(&savePort);

                    SetPort(GetWindowPort(GetControlOwner(myData->view)));

                    MouseTrackingResult mouse = kMouseTrackingMouseDown;

                    for (; mouse != kMouseTrackingMouseUp; )

                        {

                        TrackMouseLocation(NULL, &pt, &mouse);

                        if (mouse == kMouseTrackingMouseDragged)

                            {

                            SInt32 newValue = min - deltaValue + ((fBottom - pt.v - (height / 2)) * (max - min)) / (fBottom - fTop - height);

                            if (part == kControlHiIndicatorPart) SetControlHiValue(myData->view, newValue);

                            if (part == kControlLoIndicatorPart) SetControlLoValue(myData->view, newValue);

                            }

                        }

                    SetPort(savePort);

                    // let's not forget to un-hilite

                    HiliteControl(myData->view, 0);

                    SetEventParameter(inEvent, kEventParamControlPart, typeControlPartCode, sizeof(part), &part);

                    result = noErr;

                    break;

                    }

#pragma mark case kEventControlHiliteChanged

#pragma mark -

                // If anything changed, let's ask for a redraw

                case kEventControlActivate:

                case kEventControlDeactivate:

                case kEventControlHiliteChanged:

                    HIViewSetNeedsDisplay(myData->view, true);

                    result = noErr;

                    break;                  

                default:

                    break;

                }

            break;

        default:

            break;

        }

    return result;

    }

void SetControlHiLoValue(ControlRef theControl, SInt32 newValue, Boolean hiOrLo)

    {

    DoubleSliderData*   myData = (DoubleSliderData*)HIObjectDynamicCast((HIObjectRef)theControl, kDoubleSliderClassID);

    if (myData == NULL) return;

    SInt32 min = GetControl32BitMinimum(myData->invisibleHiSlider);

    SInt32 max = GetControl32BitMaximum(myData->invisibleHiSlider);

    Boolean hiChanged = false, loChanged = false;

    if (hiOrLo)

        {

        if (newValue > max) newValue = max;

        if (newValue < myData->loValue) newValue = myData->loValue;

        if (hiChanged = (newValue != myData->hiValue)) myData->hiValue = newValue;

        }

    else

        {

        if (newValue < min) newValue = min;

        if (newValue > myData->hiValue) newValue = myData->hiValue;

        if (loChanged = (newValue != myData->loValue)) myData->loValue = newValue;

        }

    if (hiChanged || loChanged)

        {

        EventRef theEvent;

        UInt32 kind = hiChanged?kEventControlHiValueFieldChanged:kEventControlLoValueFieldChanged;

        CreateEvent(NULL, kEventClassDoubleSlider, kind, 0, 0, &theEvent);

        SetEventParameter(theEvent, kEventParamDirectObject, typeControlRef, sizeof(ControlRef), &theControl);

        SendEventToEventTarget(theEvent, GetControlEventTarget(theControl));

        ReleaseEvent(theEvent);

        }

    }

// Convenience accessors

SInt32 

GetControlLoValue(ControlRef theControl)

    {

    DoubleSliderData*   myData = (DoubleSliderData*)HIObjectDynamicCast((HIObjectRef)theControl, kDoubleSliderClassID);

    if (myData)

        return myData->loValue;

    else

        return 0;

    }

void 

SetControlLoValue(

  ControlRef   theControl,

  SInt32       newLoValue)

    {

    SetControlHiLoValue(theControl, newLoValue, false);

    }

SInt32 

GetControlHiValue(ControlRef theControl)

    {

    DoubleSliderData*   myData = (DoubleSliderData*)HIObjectDynamicCast((HIObjectRef)theControl, kDoubleSliderClassID);

    if (myData)

        return myData->hiValue;

    else

        return 0;

    }

void 

SetControlHiValue(

  ControlRef   theControl,

  SInt32       newHiValue)

    {

    SetControlHiLoValue(theControl, newHiValue, true);

    }