/*
  Copyright 2012 David Robillard <http://drobilla.net>
  Copyright 2012-2019 Filipe Coelho <falktx@falktx.com>

  Permission to use, copy, modify, and/or distribute this software for any
  purpose with or without fee is hereby granted, provided that the above
  copyright notice and this permission notice appear in all copies.

  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/

/**
   @file pugl_osx.m OSX/Cocoa Pugl Implementation.
*/

#include <stdlib.h>

#ifdef PUGL_CAIRO
#import <cairo.h>
#import <cairo-quartz.h>
#endif
#import <Cocoa/Cocoa.h>

#include "pugl_internal.h"

@interface PuglWindow : NSWindow
{
@public
	PuglView* puglview;
}

- (id) initWithContentRect:(NSRect)contentRect
                 styleMask:(unsigned int)aStyle
                   backing:(NSBackingStoreType)bufferingType
                     defer:(BOOL)flag;
- (void) setPuglview:(PuglView*)view;
- (BOOL) canBecomeKeyWindow;
- (BOOL) windowShouldClose:(id)sender;
@end

@implementation PuglWindow

- (id)initWithContentRect:(NSRect)contentRect
                styleMask:(unsigned int)aStyle
                  backing:(NSBackingStoreType)bufferingType
                    defer:(BOOL)flag
{
	NSWindow* result = [super initWithContentRect:contentRect
	                                    styleMask:(NSClosableWindowMask |
	                                               NSTitledWindowMask |
	                                               NSResizableWindowMask)
	                                      backing:NSBackingStoreBuffered defer:NO];

	[result setAcceptsMouseMovedEvents:YES];
	[result setLevel: CGShieldingWindowLevel() + 1];

	return (PuglWindow*)result;

	// unused
	(void)aStyle; (void)bufferingType; (void)flag;
}

- (void)setPuglview:(PuglView*)view
{
	puglview = view;
	[self setContentSize:NSMakeSize(view->width, view->height)];
}

- (BOOL)canBecomeKeyWindow
{
	return YES;
}

- (BOOL)windowShouldClose:(id)sender
{
	if (puglview->closeFunc)
		puglview->closeFunc(puglview);
	return YES;

	// unused
	(void)sender;
}

@end

static void
puglDisplay(PuglView* view)
{
	view->redisplay = false;
	if (view->displayFunc) {
		view->displayFunc(view);
	}
}

@protocol PuglGenericView
@required
- (PuglView *) puglview;
- (void) setPuglview:(PuglView *)pv;
- (NSTrackingArea *) puglTrackingArea;
- (void) setPuglTrackingArea:(NSTrackingArea *)area;
@end

static unsigned
getModifiers(PuglView* view, NSEvent* ev)
{
	const unsigned modifierFlags = [ev modifierFlags];

	view->event_timestamp_ms = fmod([ev timestamp] * 1000.0, UINT32_MAX);

	unsigned mods = 0;
	mods |= (modifierFlags & NSShiftKeyMask)     ? PUGL_MOD_SHIFT : 0;
	mods |= (modifierFlags & NSControlKeyMask)   ? PUGL_MOD_CTRL  : 0;
	mods |= (modifierFlags & NSAlternateKeyMask) ? PUGL_MOD_ALT   : 0;
	mods |= (modifierFlags & NSCommandKeyMask)   ? PUGL_MOD_SUPER : 0;
	return mods;
}

static int
getFixedAppKitButton(NSInteger button)
{
	switch (button) {
	case 0:  return 1;
	case 1:  return 3;
	case 2:  return 2;
	default: return button;
	}
}

static void
cursorUpdate(NSView<PuglGenericView> *self, NSEvent* event)
{
	[[NSCursor arrowCursor] set];
	(void)self;
	(void)event;
}

static void
updateTrackingAreas(NSView<PuglGenericView> *self)
{
	static const int opts = NSTrackingMouseEnteredAndExited
	                      | NSTrackingMouseMoved
                          | NSTrackingEnabledDuringMouseDrag
                          | NSTrackingInVisibleRect
                          | NSTrackingActiveAlways
                          | NSTrackingCursorUpdate;

	NSTrackingArea *trackingArea = [self puglTrackingArea];
	if (trackingArea != nil) {
		[self removeTrackingArea:trackingArea];
		[trackingArea release];
	}

	trackingArea = [[NSTrackingArea alloc] initWithRect:[self bounds]
	                                            options:opts
	                                              owner:self
	                                           userInfo:nil];
	[self setPuglTrackingArea:trackingArea];
	[self addTrackingArea:trackingArea];
}

static void
viewWillMoveToWindow(NSView<PuglGenericView> *self, NSWindow* newWindow)
{
	if (newWindow != nil) {
		[newWindow setAcceptsMouseMovedEvents:YES];
		[newWindow makeFirstResponder:self];
	}
}

static void
reshape(NSView<PuglGenericView> *self)
{
	PuglView* puglview = [self puglview];

	NSRect bounds = [self bounds];
	int    width  = bounds.size.width;
	int    height = bounds.size.height;

	puglEnterContext(puglview);

	if (puglview->reshapeFunc) {
		puglview->reshapeFunc(puglview, width, height);
	} else {
		puglDefaultReshape(width, height);
	}

	puglLeaveContext(puglview, false);

	puglview->width  = width;
	puglview->height = height;
}

static void
mouseMoved(NSView<PuglGenericView> *self, NSEvent *event)
{
	PuglView* puglview = [self puglview];

	if (puglview->motionFunc) {
		NSPoint loc = [self convertPoint:[event locationInWindow] fromView:nil];
		puglview->mods = getModifiers(puglview, event);
		puglview->motionFunc(puglview, loc.x, loc.y);
	}
}

static void
mouseDown(NSView<PuglGenericView> *self, NSEvent *event)
{
	PuglView* puglview = [self puglview];

	if (puglview->mouseFunc) {
		NSPoint loc = [self convertPoint:[event locationInWindow] fromView:nil];
		puglview->mods = getModifiers(puglview, event);
		puglview->mouseFunc(puglview, getFixedAppKitButton([event buttonNumber]), true, loc.x, loc.y);
	}
}

static void
mouseUp(NSView<PuglGenericView> *self, NSEvent *event)
{
	PuglView* puglview = [self puglview];

	if (puglview->mouseFunc) {
		NSPoint loc = [self convertPoint:[event locationInWindow] fromView:nil];
		puglview->mods = getModifiers(puglview, event);
		puglview->mouseFunc(puglview, getFixedAppKitButton([event buttonNumber]), false, loc.x, loc.y);
	}
}

static void
scrollWheel(NSView<PuglGenericView> *self, NSEvent *event)
{
	PuglView* puglview = [self puglview];

	if (puglview->scrollFunc) {
		NSPoint loc = [self convertPoint:[event locationInWindow] fromView:nil];
		puglview->mods = getModifiers(puglview, event);
		puglview->scrollFunc(puglview,
		                     loc.x, loc.y,
		                     [event deltaX], [event deltaY]);
	}
}

static void
keyDown(NSView<PuglGenericView> *self, NSEvent *event)
{
	PuglView* puglview = [self puglview];

	if (puglview->keyboardFunc && !(puglview->ignoreKeyRepeat && [event isARepeat])) {
		NSString* chars = [event characters];
		puglview->mods = getModifiers(puglview, event);
		puglview->keyboardFunc(puglview, true, [chars characterAtIndex:0]);
	}
}

static void
keyUp(NSView<PuglGenericView> *self, NSEvent *event)
{
	PuglView* puglview = [self puglview];

	if (puglview->keyboardFunc) {
		NSString* chars = [event characters];
		puglview->mods = getModifiers(puglview, event);
		puglview->keyboardFunc(puglview, false, [chars characterAtIndex:0]);
	}
}

static void
flagsChanged(NSView<PuglGenericView> *self, NSEvent *event)
{
	PuglView* puglview = [self puglview];

	if (puglview->specialFunc) {
		const unsigned mods = getModifiers(puglview, event);
		if ((mods & PUGL_MOD_SHIFT) != (puglview->mods & PUGL_MOD_SHIFT)) {
			puglview->specialFunc(puglview, mods & PUGL_MOD_SHIFT, PUGL_KEY_SHIFT);
		} else if ((mods & PUGL_MOD_CTRL) != (puglview->mods & PUGL_MOD_CTRL)) {
			puglview->specialFunc(puglview, mods & PUGL_MOD_CTRL, PUGL_KEY_CTRL);
		} else if ((mods & PUGL_MOD_ALT) != (puglview->mods & PUGL_MOD_ALT)) {
			puglview->specialFunc(puglview, mods & PUGL_MOD_ALT, PUGL_KEY_ALT);
		} else if ((mods & PUGL_MOD_SUPER) != (puglview->mods & PUGL_MOD_SUPER)) {
			puglview->specialFunc(puglview, mods & PUGL_MOD_SUPER, PUGL_KEY_SUPER);
		}
		puglview->mods = mods;
	}
}

#ifdef PUGL_OPENGL
@interface PuglOpenGLView : NSOpenGLView<PuglGenericView>
{
@public
	PuglView* puglview;
	NSTrackingArea* trackingArea;
	bool doubleBuffered;
}

- (PuglView *) puglview;
- (void) setPuglview:(PuglView *)pv;
- (NSTrackingArea *) puglTrackingArea;
- (void) setPuglTrackingArea:(NSTrackingArea *)area;

- (BOOL) acceptsFirstMouse:(NSEvent*)e;
- (BOOL) acceptsFirstResponder;
- (BOOL) isFlipped;
- (BOOL) isOpaque;
- (BOOL) preservesContentInLiveResize;
- (id)   initWithFrame:(NSRect)frame;
- (void) reshape;
- (void) drawRect:(NSRect)r;
- (void) cursorUpdate:(NSEvent*)e;
- (void) updateTrackingAreas;
- (void) viewWillMoveToWindow:(NSWindow*)newWindow;
- (void) mouseMoved:(NSEvent*)event;
- (void) mouseDragged:(NSEvent*)event;
- (void) rightMouseDragged:(NSEvent*)event;
- (void) otherMouseDragged:(NSEvent*)event;
- (void) mouseDown:(NSEvent*)event;
- (void) rightMouseDown:(NSEvent*)event;
- (void) otherMouseDown:(NSEvent*)event;
- (void) mouseUp:(NSEvent*)event;
- (void) rightMouseUp:(NSEvent*)event;
- (void) otherMouseUp:(NSEvent*)event;
- (void) scrollWheel:(NSEvent*)event;
- (void) keyDown:(NSEvent*)event;
- (void) keyUp:(NSEvent*)event;
- (void) flagsChanged:(NSEvent*)event;

@end

@implementation PuglOpenGLView
- (PuglView *) puglview {
	return self->puglview;
}

- (void) setPuglview:(PuglView *)pv {
	self->puglview = pv;
}

- (NSTrackingArea *) puglTrackingArea {
	return self->trackingArea;
}

- (void) setPuglTrackingArea:(NSTrackingArea *)area {
	self->trackingArea = area;
}

- (BOOL) acceptsFirstMouse:(NSEvent*)e
{
	return YES;

	// unused
	(void)e;
}

- (BOOL) acceptsFirstResponder
{
	return YES;
}

- (BOOL) isFlipped
{
	return YES;
}

- (BOOL) isOpaque
{
	return YES;
}

- (BOOL) preservesContentInLiveResize
{
	return NO;
}

- (id) initWithFrame:(NSRect)frame
{
	puglview       = nil;
	trackingArea   = nil;
	doubleBuffered = true;

	NSOpenGLPixelFormatAttribute pixelAttribs[] = {
		NSOpenGLPFAColorSize, 24,
		NSOpenGLPFAAlphaSize, 8,
		NSOpenGLPFADepthSize, 16,
		NSOpenGLPFADoubleBuffer,
		NSOpenGLPFAAccelerated,
		0
	};

	NSOpenGLPixelFormat* pixelFormat = [[NSOpenGLPixelFormat alloc]
		              initWithAttributes:pixelAttribs];

	if (pixelFormat) {
		self = [super initWithFrame:frame pixelFormat:pixelFormat];
		[pixelFormat release];
		printf("Is doubleBuffered? TRUE\n");
	} else {
		self = [super initWithFrame:frame];
		doubleBuffered = false;
		printf("Is doubleBuffered? FALSE\n");
	}

	if (self) {
		GLint swapInterval = 1;
		[[self openGLContext] setValues:&swapInterval forParameter:NSOpenGLCPSwapInterval];

		[self reshape];
	}

	return self;
}

- (void) reshape
{
	if (!puglview) {
		/* NOTE: Apparently reshape gets called when the GC gets around to
		   deleting the view (?), so we must have reset puglview to NULL when
		   this comes around.
		*/
		return;
	}

	[[self openGLContext] update];

	reshape(self);
}

- (void) drawRect:(NSRect)r
{
	puglEnterContext(puglview);
	puglDisplay(puglview);
	puglLeaveContext(puglview, true);

	// unused
	return; (void)r;
}

- (void) cursorUpdate:(NSEvent*)e
{
	cursorUpdate(self, e);
}

- (void) updateTrackingAreas
{
	updateTrackingAreas(self);
	[super updateTrackingAreas];
}

- (void) viewWillMoveToWindow:(NSWindow*)newWindow
{
	viewWillMoveToWindow(self, newWindow);
	[super viewWillMoveToWindow:newWindow];
}

- (void) mouseMoved:(NSEvent*)event
{
	mouseMoved(self, event);
}

- (void) mouseDragged:(NSEvent*)event
{
	mouseMoved(self, event);
}

- (void) rightMouseDragged:(NSEvent*)event
{
	mouseMoved(self, event);
}

- (void) otherMouseDragged:(NSEvent*)event
{
	mouseMoved(self, event);
}

- (void) mouseDown:(NSEvent*)event
{
	mouseDown(self, event);
}

- (void) rightMouseDown:(NSEvent*)event
{
	mouseDown(self, event);
}

- (void) otherMouseDown:(NSEvent*)event
{
	mouseDown(self, event);
}

- (void) mouseUp:(NSEvent*)event
{
	mouseUp(self, event);
}

- (void) rightMouseUp:(NSEvent*)event
{
	mouseUp(self, event);
}

- (void) otherMouseUp:(NSEvent*)event
{
	mouseUp(self, event);
}

- (void) scrollWheel:(NSEvent*)event
{
	scrollWheel(self, event);
}

- (void) keyDown:(NSEvent*)event
{
	keyDown(self, event);
}

- (void) keyUp:(NSEvent*)event
{
	keyUp(self, event);
}

- (void) flagsChanged:(NSEvent*)event
{
	flagsChanged(self, event);
}

@end
#endif

#ifdef PUGL_CAIRO
@interface PuglCairoView : NSView<PuglGenericView>
{
	PuglView* puglview;
	cairo_t* cr;
	NSTrackingArea* trackingArea;
}

- (PuglView *) puglview;
- (void) setPuglview:(PuglView *)pv;
- (NSTrackingArea *) puglTrackingArea;
- (void) setPuglTrackingArea:(NSTrackingArea *)area;

- (cairo_t *) cairoContext;

- (BOOL) acceptsFirstMouse:(NSEvent*)e;
- (BOOL) acceptsFirstResponder;
- (BOOL) isFlipped;
- (BOOL) isOpaque;
- (BOOL) preservesContentInLiveResize;
- (id) initWithFrame:(NSRect)frame;
- (void) reshape;
- (void) drawRect:(NSRect)r;
- (void) cursorUpdate:(NSEvent*)e;
- (void) updateTrackingAreas;
- (void) viewWillMoveToWindow:(NSWindow*)newWindow;
- (void) mouseMoved:(NSEvent*)event;
- (void) mouseDragged:(NSEvent*)event;
- (void) rightMouseDragged:(NSEvent*)event;
- (void) otherMouseDragged:(NSEvent*)event;
- (void) mouseDown:(NSEvent*)event;
- (void) rightMouseDown:(NSEvent*)event;
- (void) otherMouseDown:(NSEvent*)event;
- (void) mouseUp:(NSEvent*)event;
- (void) rightMouseUp:(NSEvent*)event;
- (void) otherMouseUp:(NSEvent*)event;
- (void) scrollWheel:(NSEvent*)event;
- (void) keyDown:(NSEvent*)event;
- (void) keyUp:(NSEvent*)event;
- (void) flagsChanged:(NSEvent*)event;
@end

@implementation PuglCairoView
- (PuglView *) puglview {
	return self->puglview;
}

- (void) setPuglview:(PuglView *)pv {
	self->puglview = pv;
}

- (NSTrackingArea *) puglTrackingArea {
	return self->trackingArea;
}

- (void) setPuglTrackingArea:(NSTrackingArea *)area {
	self->trackingArea = area;
}

- (cairo_t *) cairoContext {
	return cr;
}

- (BOOL) acceptsFirstMouse:(NSEvent*)e
{
	return YES;

	// unused
	(void)e;
}

- (BOOL) acceptsFirstResponder
{
	return YES;
}

- (BOOL) isFlipped
{
	return YES;
}

- (BOOL) isOpaque
{
	return YES;
}

- (BOOL) preservesContentInLiveResize
{
	return NO;
}

- (id) initWithFrame:(NSRect)frame {
	puglview       = nil;
	cr             = NULL;
	trackingArea   = nil;
	[super initWithFrame:frame];
	return self;
}

- (void) reshape
{
	if (!puglview) {
		/* NOTE: Apparently reshape gets called when the GC gets around to
		   deleting the view (?), so we must have reset puglview to NULL when
		   this comes around.
		*/
		return;
	}

	reshape(self);
}

- (void) drawRect:(NSRect)r {
	CGContextRef ctx = (CGContextRef)[[NSGraphicsContext currentContext] graphicsPort];
	NSRect bounds = [self bounds];
	cairo_surface_t* surface;
	cairo_t* cairo;

	surface = cairo_quartz_surface_create_for_cg_context(ctx, bounds.size.width, bounds.size.height);
	if (surface) {
		cairo  = cairo_create(surface);
		if (cairo) {
			self->cr = cairo;
			puglEnterContext(puglview);
			puglDisplay(puglview);
			puglLeaveContext(puglview, true);
			self->cr = NULL;
			cairo_destroy(cairo);
		}
		cairo_surface_destroy(surface);
	}
}

- (void) cursorUpdate:(NSEvent*)e
{
	cursorUpdate(self, e);
}

- (void) updateTrackingAreas
{
	updateTrackingAreas(self);
	[super updateTrackingAreas];
}

- (void) viewWillMoveToWindow:(NSWindow*)newWindow
{
	viewWillMoveToWindow(self, newWindow);
	[super viewWillMoveToWindow:newWindow];
}

- (void) mouseMoved:(NSEvent*)event
{
	mouseMoved(self, event);
}

- (void) mouseDragged:(NSEvent*)event
{
	mouseMoved(self, event);
}

- (void) rightMouseDragged:(NSEvent*)event
{
	mouseMoved(self, event);
}

- (void) otherMouseDragged:(NSEvent*)event
{
	mouseMoved(self, event);
}

- (void) mouseDown:(NSEvent*)event
{
	mouseDown(self, event);
}

- (void) rightMouseDown:(NSEvent*)event
{
	mouseDown(self, event);
}

- (void) otherMouseDown:(NSEvent*)event
{
	mouseDown(self, event);
}

- (void) mouseUp:(NSEvent*)event
{
	mouseUp(self, event);
}

- (void) rightMouseUp:(NSEvent*)event
{
	mouseUp(self, event);
}

- (void) otherMouseUp:(NSEvent*)event
{
	mouseUp(self, event);
}

- (void) scrollWheel:(NSEvent*)event
{
	scrollWheel(self, event);
}

- (void) keyDown:(NSEvent*)event
{
	keyDown(self, event);
}

- (void) keyUp:(NSEvent*)event
{
	keyUp(self, event);
}

- (void) flagsChanged:(NSEvent*)event
{
	flagsChanged(self, event);
}
@end
#endif

struct PuglInternalsImpl {
	union {
		NSView<PuglGenericView>* view;
#ifdef PUGL_OPENGL
		PuglOpenGLView* glview;
#endif
#ifdef PUGL_CAIRO
		PuglCairoView* cairoview;
#endif
	};
	id              window;
};

PuglInternals*
puglInitInternals()
{
	return (PuglInternals*)calloc(1, sizeof(PuglInternals));
}

void
puglEnterContext(PuglView* view)
{
#ifdef PUGL_OPENGL
	[[view->impl->glview openGLContext] makeCurrentContext];
#endif
}

void
puglLeaveContext(PuglView* view, bool flush)
{
	if (flush) {
#ifdef PUGL_OPENGL
		if (view->impl->glview->doubleBuffered) {
			[[view->impl->glview openGLContext] flushBuffer];
		} else {
			glFlush();
		}
		//[NSOpenGLContext clearCurrentContext];
#endif
	}
}

int
puglCreateWindow(PuglView* view, const char* title)
{
	PuglInternals* impl = view->impl;

	[NSAutoreleasePool new];
	[NSApplication sharedApplication];

#ifdef PUGL_OPENGL
	impl->glview = [PuglOpenGLView new];
#endif
#ifdef PUGL_CAIRO
	impl->cairoview = [PuglCairoView new];
#endif

	if (!impl->view) {
		return 1;
	}

	[impl->view setPuglview:view];

	if (view->user_resizable) {
		[impl->view setAutoresizingMask:NSViewWidthSizable|NSViewHeightSizable];
	}

	if (view->parent) {
		[impl->view retain];
		NSView* pview = (NSView*)view->parent;
		[pview addSubview:impl->view];
	 	return 0;
	}

	id window = [[PuglWindow new]retain];

	if (title) {
		NSString* titleString = [[NSString alloc]
					  initWithBytes:title
					         length:strlen(title)
					       encoding:NSUTF8StringEncoding];

		[window setTitle:titleString];
	}

	[window setPuglview:view];
	[window setContentView:impl->view];
	[window makeFirstResponder:impl->view];
	[window makeKeyAndOrderFront:window];

	// wait for first puglShowWindow
	[window setIsVisible:NO];

	[NSApp activateIgnoringOtherApps:YES];
	[window center];

	impl->window = window;

	return 0;
}

void
puglShowWindow(PuglView* view)
{
	PuglInternals* impl = view->impl;

	if (impl->window) {
		[impl->window setIsVisible:YES];
	} else {
		[view->impl->view setHidden:NO];
	}
}

void
puglHideWindow(PuglView* view)
{
	PuglInternals* impl = view->impl;

	if (impl->window) {
		[impl->window setIsVisible:NO];
	} else {
		[impl->view setHidden:YES];
	}
}

void
puglDestroy(PuglView* view)
{
	[view->impl->view setPuglview:NULL];

	if (view->impl->window) {
		[view->impl->window close];
		[view->impl->view release];
		[view->impl->window release];
	} else {
		[view->impl->view release];
	}

	free(view->impl);
	free(view);
}

PuglStatus
puglProcessEvents(PuglView* view)
{
	return PUGL_SUCCESS;

	// unused
	(void)view;
}

void
puglPostRedisplay(PuglView* view)
{
	view->redisplay = true;
	[view->impl->view setNeedsDisplay:YES];
}

PuglNativeWindow
puglGetNativeWindow(PuglView* view)
{
	return (PuglNativeWindow)view->impl->view;
}

void*
puglGetContext(PuglView* view)
{
#ifdef PUGL_CAIRO
	return [view->impl->cairoview cairoContext];
#endif
	return NULL;

	// may be unused
	(void)view;
}

int
puglUpdateGeometryConstraints(PuglView* view, int min_width, int min_height, bool aspect)
{
	// TODO
	return 1;

	(void)view;
	(void)min_width;
	(void)min_height;
	(void)aspect;
}