Avalonia/native/Avalonia.Native/src/OSX/WindowImpl.mm

//
// Created by Dan Walmsley on 04/05/2022.
// Copyright (c) 2022 Avalonia. All rights reserved.
//

#import <AppKit/AppKit.h>
#include "AutoFitContentView.h"
#include "AvnView.h"
#include "automation.h"
#include "WindowProtocol.h"
#include "WindowImpl.h"

WindowImpl::WindowImpl(IAvnWindowEvents *events) : TopLevelImpl(events), WindowBaseImpl(events, false) {
    _isEnabled = true;
    _isClientAreaExtended = false;
    _fullScreenActive = false;
    _canResize = true;
    _canMinimize = true;
    _canMaximize = true;
    _decorations = SystemDecorationsFull;
    _transitioningWindowState = false;
    _inSetWindowState = false;
    _lastWindowState = Normal;
    _actualWindowState = Normal;
    _lastTitle = @"";
    Parent = nullptr;
    WindowEvents = events;

    [Window setHasShadow:true];
    
    OnInitialiseNSWindow();
}

void WindowImpl::OnInitialiseNSWindow(){
    [GetWindowProtocol() setCanBecomeKeyWindow:true];
    
    [Window disableCursorRects];
    [Window setTabbingMode:NSWindowTabbingModeDisallowed];
    [Window setCollectionBehavior:NSWindowCollectionBehaviorFullScreenPrimary];

    [Window setTitle:_lastTitle];
    
    if(_isClientAreaExtended)
    {
        [GetWindowProtocol() setIsExtended:true];
        SetExtendClientArea(true);
    }
}

HRESULT WindowImpl::Show(bool activate, bool isDialog) {
    START_COM_CALL;

    @autoreleasepool {
        _isModal = isDialog;

        WindowBaseImpl::Show(activate, isDialog);
        GetWindowState(&_actualWindowState);

        if(IsZoomed()) {
            _lastWindowState = _actualWindowState;
        }

        return SetWindowState(_lastWindowState);
    }
}

HRESULT WindowImpl::SetEnabled(bool enable) {
    START_COM_CALL;

    @autoreleasepool {
        _isEnabled = enable;
        [GetWindowProtocol() setEnabled:enable];
        UpdateAppearance();
        return S_OK;
    }
}

void WindowImpl::BringToFront()
{
    if(Window != nullptr)
    {
        if ([Window isVisible] && ![Window isMiniaturized])
        {
            if(IsModal())
            {
                Activate();
            }
            else
            {
                [Window orderFront:nullptr];
            }
        }
        
        [Window invalidateShadow];
        ZOrderChildWindows();
    }
}

void WindowImpl::ZOrderChildWindows()
{
    for(auto iterator = _children.begin(); iterator != _children.end(); iterator++)
    {
        auto window = (*iterator)->Window;
        
        // #9565: Only bring window to front if it's on the currently active space
        if ([window isOnActiveSpace]) {
            (*iterator)->BringToFront();
        }
    }
}

bool WindowImpl::CanBecomeKeyWindow()
{
    for(auto iterator = _children.begin(); iterator != _children.end(); iterator++)
    {
        if((*iterator)->IsModal())
        {
            return false;
        }
    }
    
    return true;
}

void WindowImpl::StartStateTransition() {
    _transitioningWindowState = true;
    UpdateAppearance();
}

void WindowImpl::EndStateTransition() {
    _transitioningWindowState = false;
    UpdateAppearance();

    // Ensure correct order of child windows after fullscreen transition.
    ZOrderChildWindows();
}

SystemDecorations WindowImpl::Decorations() {
    return _decorations;
}

AvnWindowState WindowImpl::WindowState() {
    return _lastWindowState;
}

void WindowImpl::WindowStateChanged() {
    if (_shown && !_inSetWindowState && !_transitioningWindowState) {
        AvnWindowState state;
        GetWindowState(&state);

        if (_lastWindowState != state) {
            if (_isClientAreaExtended) {
                if (_lastWindowState == FullScreen) {
                    // we exited fs.
                    [Window setTitlebarAppearsTransparent:true];

                    [StandardContainer setFrameSize:StandardContainer.frame.size];
                } else if (state == FullScreen) {
                    // we entered fs.
                    [Window setTitlebarAppearsTransparent:false];

                    [StandardContainer setFrameSize:StandardContainer.frame.size];
                }
            }

            _lastWindowState = state;
            _actualWindowState = state;
            WindowEvents->WindowStateChanged(state);
        }
    }
}

bool WindowImpl::UndecoratedIsMaximized() {
    auto windowSize = [Window frame];
    auto available = [Window screen].visibleFrame;
    return CGRectEqualToRect(windowSize, available);
}

bool WindowImpl::IsZoomed() {
    return _decorations == SystemDecorationsFull ? [Window isZoomed] : UndecoratedIsMaximized();
}

void WindowImpl::DoZoom() {
    if (_decorations == SystemDecorationsNone ||
        _decorations == SystemDecorationsBorderOnly ||
        _canResize == false ||
        _canMaximize == false) {
        [Window setFrame:[Window screen].visibleFrame display:true];
    } else {
        [Window performZoom:Window];
    }
}

HRESULT WindowImpl::SetCanResize(bool value) {
    START_COM_CALL;

    @autoreleasepool {
        _canResize = value;
        UpdateAppearance();
        return S_OK;
    }
}

HRESULT WindowImpl::SetCanMinimize(bool value) {
    START_COM_ARP_CALL;

    _canMinimize = value;
    UpdateAppearance();
    return S_OK;
}

HRESULT WindowImpl::SetCanMaximize(bool value) {
    START_COM_ARP_CALL;

    _canMaximize = value;
    UpdateAppearance();
    return S_OK;
}

HRESULT WindowImpl::SetDecorations(SystemDecorations value) {
    START_COM_CALL;

    @autoreleasepool {
        auto currentWindowState = _lastWindowState;
        _decorations = value;

        if (_fullScreenActive) {
            return S_OK;
        }

        UpdateAppearance();

        if (_isClientAreaExtended) {
            [StandardContainer ShowTitleBar:_decorations == SystemDecorationsFull];
        }

        switch (_decorations) {
            case SystemDecorationsNone:
                [Window setHasShadow:NO];
                [Window setTitleVisibility:NSWindowTitleHidden];
                [Window setTitlebarAppearsTransparent:YES];

                if (currentWindowState == Maximized) {
                    if (!UndecoratedIsMaximized()) {
                        DoZoom();
                    }
                }
                break;

            case SystemDecorationsBorderOnly:
                [Window setHasShadow:YES];
                [Window setTitleVisibility:NSWindowTitleHidden];
                [Window setTitlebarAppearsTransparent:YES];

                if (currentWindowState == Maximized) {
                    if (!UndecoratedIsMaximized()) {
                        DoZoom();
                    }
                }
                break;

            case SystemDecorationsFull:
                [Window setHasShadow:YES];
                [Window setTitle:_lastTitle];

                if (!_isClientAreaExtended) {
                    [Window setTitleVisibility:NSWindowTitleVisible];
                    [Window setTitlebarAppearsTransparent:NO];
                }

                if (currentWindowState == Maximized) {
                    auto newFrame = [Window contentRectForFrameRect:[Window frame]].size;

                    [View setFrameSize:newFrame];
                }
                break;
        }

        return S_OK;
    }
}

HRESULT WindowImpl::SetTitle(char *utf8title) {
    START_COM_CALL;

    @autoreleasepool {
        _lastTitle = [NSString stringWithUTF8String:(const char *) utf8title];
        [Window setTitle:_lastTitle];

        return S_OK;
    }
}

HRESULT WindowImpl::SetTitleBarColor(AvnColor color) {
    START_COM_CALL;

    @autoreleasepool {
        float a = (float) color.Alpha / 255.0f;
        float r = (float) color.Red / 255.0f;
        float g = (float) color.Green / 255.0f;
        float b = (float) color.Blue / 255.0f;

        auto nscolor = [NSColor colorWithSRGBRed:r green:g blue:b alpha:a];

        // Based on the titlebar color we have to choose either light or dark
        // OSX doesnt let you set a foreground color for titlebar.
        if ((r * 0.299 + g * 0.587 + b * 0.114) > 186.0f / 255.0f) {
            [Window setAppearance:[NSAppearance appearanceNamed:NSAppearanceNameVibrantLight]];
        } else {
            [Window setAppearance:[NSAppearance appearanceNamed:NSAppearanceNameVibrantDark]];
        }

        [Window setTitlebarAppearsTransparent:true];
        [Window setBackgroundColor:nscolor];
    }

    return S_OK;
}

HRESULT WindowImpl::GetWindowState(AvnWindowState *ret) {
    START_COM_CALL;

    @autoreleasepool {
        if (ret == nullptr) {
            return E_POINTER;
        }

        if (([Window styleMask] & NSWindowStyleMaskFullScreen) == NSWindowStyleMaskFullScreen) {
            *ret = FullScreen;
            return S_OK;
        }

        if ([Window isMiniaturized]) {
            *ret = Minimized;
            return S_OK;
        }

        if (IsZoomed()) {
            *ret = Maximized;
            return S_OK;
        }

        *ret = Normal;

        return S_OK;
    }
}

HRESULT WindowImpl::GetWindowZOrder(long* zOrder) {
    START_COM_CALL;
    @autoreleasepool {
        if (zOrder == nullptr) {
            return E_POINTER;
        }

        // negate the value to match expected z-order in Avalonia
        // (top-most window should have the highest z-order value)
        *zOrder = -[Window orderedIndex];
        return S_OK;
    }
}

HRESULT WindowImpl::TakeFocusFromChildren() {
    START_COM_CALL;

    @autoreleasepool {
        if (Window == nil)
            return S_OK;
        if ([Window isKeyWindow])
            [Window makeFirstResponder:View];

        return S_OK;
    }
}

HRESULT WindowImpl::SetExtendClientArea(bool enable) {
    START_COM_CALL;

    @autoreleasepool {
        _isClientAreaExtended = enable;

        if(Window != nullptr) {
            if (enable) {
                Window.titleVisibility = NSWindowTitleHidden;

                [Window setTitlebarAppearsTransparent:true];

                [StandardContainer ShowTitleBar:_decorations == SystemDecorationsFull];

                Window.toolbar = nullptr;
            } else {
                Window.titleVisibility = NSWindowTitleVisible;
                Window.toolbar = nullptr;
                [Window setTitlebarAppearsTransparent:false];
                View.layer.zPosition = 0;
            }

            [GetWindowProtocol() setIsExtended:enable];
            UpdateAppearance();
        }

        return S_OK;
    }
}

HRESULT WindowImpl::GetExtendTitleBarHeight(double *ret) {
    START_COM_CALL;

    @autoreleasepool {
        if (ret == nullptr) {
            return E_POINTER;
        }

        *ret = [GetWindowProtocol() getExtendedTitleBarHeight];

        return S_OK;
    }
}

HRESULT WindowImpl::SetExtendTitleBarHeight(double value) {
    START_COM_CALL;

    @autoreleasepool {
        [StandardContainer SetTitleBarHeightHint:value];
        return S_OK;
    }
}

void WindowImpl::EnterFullScreenMode() {
    _fullScreenActive = true;

    [Window setTitle:_lastTitle];
    [Window toggleFullScreen:nullptr];
}

void WindowImpl::ExitFullScreenMode() {
    [Window toggleFullScreen:nullptr];

    _fullScreenActive = false;

    SetDecorations(_decorations);
}

HRESULT WindowImpl::SetWindowState(AvnWindowState state) {
    return SetWindowState(state, true);
}

HRESULT WindowImpl::SetWindowState(AvnWindowState state, bool shouldResize) {
    START_COM_CALL;

    @autoreleasepool {
        auto currentState = _actualWindowState;
        _lastWindowState = state;

        if (Window == nullptr) {
            return S_OK;
        }

        if (_actualWindowState == state) {
            return S_OK;
        }

        _inSetWindowState = true;

        if (currentState == Normal) {
            _preZoomSize = [Window frame];
        }

        if (_shown) {
            _actualWindowState = _lastWindowState;

            if (shouldResize) {
                switch (state) {
                    case Maximized:
                        if (currentState == FullScreen) {
                            ExitFullScreenMode();
                        }

                        lastPositionSet.X = 0;
                        lastPositionSet.Y = 0;

                        if ([Window isMiniaturized]) {
                            [Window deminiaturize:Window];
                        }

                        if (!IsZoomed()) {
                            DoZoom();
                        }
                        break;

                    case Minimized:
                        if (currentState == FullScreen) {
                            ExitFullScreenMode();
                        } else {
                            [Window miniaturize:Window];
                        }
                        break;

                    case FullScreen:
                        if ([Window isMiniaturized]) {
                            [Window deminiaturize:Window];
                        }

                        EnterFullScreenMode();
                        break;

                    case Normal:
                        if ([Window isMiniaturized]) {
                            [Window deminiaturize:Window];
                        }

                        if (currentState == FullScreen) {
                            ExitFullScreenMode();
                        }

                        if (IsZoomed()) {
                            if (_decorations == SystemDecorationsFull) {
                                DoZoom();
                            } else {
                                [Window setFrame:_preZoomSize display:true];
                                auto newFrame = [Window contentRectForFrameRect:[Window frame]].size;

                                [View setFrameSize:newFrame];
                            }

                        }
                        break;
                }
            }

            WindowEvents->WindowStateChanged(_actualWindowState);
        }


        _inSetWindowState = false;

        return S_OK;
    }
}

bool WindowImpl::IsModal() {
    return _isModal;
}

bool WindowImpl::IsOwned() {
    return Parent.tryGet() != nullptr;
}

NSWindowStyleMask WindowImpl::CalculateStyleMask() {
    // Use the current style mask and only clear the flags we're going to be modifying.
    unsigned long s = [Window styleMask] &
        ~(NSWindowStyleMaskFullSizeContentView |
          NSWindowStyleMaskTitled |
          NSWindowStyleMaskClosable |
          NSWindowStyleMaskResizable |
          NSWindowStyleMaskMiniaturizable |
          NSWindowStyleMaskTexturedBackground);
    
    switch (_decorations) {
        case SystemDecorationsNone:
            s = s | NSWindowStyleMaskFullSizeContentView;
            break;

        case SystemDecorationsBorderOnly:
            s = s | NSWindowStyleMaskTitled | NSWindowStyleMaskFullSizeContentView;
            break;

        case SystemDecorationsFull:
            s = s | NSWindowStyleMaskTitled | NSWindowStyleMaskClosable;

            if ((_canResize && _isEnabled) || _transitioningWindowState) {
                s = s | NSWindowStyleMaskResizable;
            }
            break;
    }

    if (_canMinimize && !IsOwned()) {
        s |= NSWindowStyleMaskMiniaturizable;
    }

    if (_isClientAreaExtended) {
        s |= NSWindowStyleMaskFullSizeContentView | NSWindowStyleMaskTexturedBackground;
    }
    return s;
}

void WindowImpl::UpdateAppearance() {
    WindowBaseImpl::UpdateAppearance();
    
    if (Window == nil) {
        return;
    }

    bool hasTrafficLights = (_decorations == SystemDecorationsFull);
    
    NSButton* closeButton = [Window standardWindowButton:NSWindowCloseButton];
    NSButton* miniaturizeButton = [Window standardWindowButton:NSWindowMiniaturizeButton];
    NSButton* zoomButton = [Window standardWindowButton:NSWindowZoomButton];

    [closeButton setHidden:!hasTrafficLights];
    [closeButton setEnabled:_isEnabled];
    [miniaturizeButton setHidden:!hasTrafficLights];
    [miniaturizeButton setEnabled:_isEnabled && _canMinimize];
    [zoomButton setHidden:!hasTrafficLights];
    [zoomButton setEnabled:CanZoom() || (([Window styleMask] & NSWindowStyleMaskFullScreen) != 0 && _isEnabled)];
}

extern IAvnWindow* CreateAvnWindow(IAvnWindowEvents*events)
{
    @autoreleasepool
    {
        IAvnWindow* ptr = (IAvnWindow*)new WindowImpl(events);
        return ptr;
    }
}