#include "private.h"

#include "sprite.h"

#include "world.h"

#include "group.h"

#include "drawing.h"

struct _Sprite {

	double x;

	double y;

	double rotation;

	double width;

	double height;

	double scale;

	double vx;

	double vy;

	double rotationSpeed;

	HeliCollider collider;

	double bounciness;

	int rotateToDirection;

	int mirrorX;

	int mirrorY;

	double depth;

	double lifeTime;

	int visible;

	int tag;

	int debug;

	double shapeColor[4];

	double tintColor[4];

	int playing;

	int frame;

	HeliArray groups;

	HeliAnimation *animation;

};

static HeliArray sprites;

static HeliArray spritesSorted;

static void prepareCollider(Sprite sprite, HeliCollider *collider) {

	collider->type = sprite->collider.type;

	collider->x = sprite->collider.x + sprite->x;

	collider->y = sprite->collider.y + sprite->y;

	collider->width = sprite->collider.width;

	collider->height = sprite->collider.height;

	collider->radius = sprite->collider.radius;

	collider->rotation = sprite->collider.rotation + sprite->rotation;

	// auto-size

	if (collider->type == COLLIDER_RECTANGLE) {

		if (collider->width < -HELI_PRECISION) collider->width = sprite->width;

		if (collider->height < -HELI_PRECISION) collider->height = sprite->height;

		if (collider->radius < -HELI_PRECISION) collider->radius = 0;

	} else

	if (collider->type == COLLIDER_CIRCLE) {

		collider->width = 0;

		collider->height = 0;

		if (collider->radius < -HELI_PRECISION) collider->radius = 0.5*sprite->width;

	}

	// scale

	collider->width *= sprite->scale;

	collider->height *= sprite->scale;

	collider->radius *= sprite->scale;

	// fix small values

	if (collider->width  < HELI_PRECISION) collider->width = HELI_PRECISION;

	if (collider->height < HELI_PRECISION) collider->height = HELI_PRECISION;

	if (collider->radius < HELI_PRECISION) collider->radius = HELI_PRECISION;

	// fix round corners

	if (collider->type == COLLIDER_RECTANGLE) {

		double rmax = 0.5*( collider->width < collider->height

						  ? collider->width : collider->height );

		if (collider->radius >= rmax - HELI_PRECISION)

			collider->radius = rmax;

		collider->width  -= 2*collider->radius;

		collider->height -= 2*collider->radius;

	}

}

Sprite createSpriteEx(double x, double y, double width, double height) {

	if (!heliInitialized) return NULL;

	Sprite s = calloc(1, sizeof(*s));

	s->x = x;

	s->y = y;

	s->width = width;

	s->height = height;

	s->scale = 1;

	s->collider.type = COLLIDER_RECTANGLE;

	s->collider.width = s->collider.height = -1;

	s->bounciness = 1;

	s->mirrorX = 1;

	s->mirrorY = 1;

	s->lifeTime = -1;

	s->visible = TRUE;

	s->shapeColor[0] = s->shapeColor[1] = s->shapeColor[2] = 0.5;

	s->shapeColor[3] = 1;

	s->tintColor[0] = s->tintColor[1] = s->tintColor[2] = s->tintColor[3] = 1;

	heliArrayInsert(&sprites, -1, s, NULL);

	heliArrayInsert(&spritesSorted, -1, s, NULL);

	heliObjectRegister(s, (HeliFreeCallback)&spriteDestroy);

	return s;

}

Sprite createSprite(double x, double y)

	{ return createSpriteEx(x, y, 100, 100); }

void spriteDestroy(Sprite sprite) {

	heliObjectUnregister(sprite);

	spriteSetNoAnimation(sprite);

	while(sprite->groups.count > 0)

		groupRemove((Group)sprite->groups.items[0].value, sprite);

	for(int i = 0; i < sprites.count; ++i)

		if (sprites.items[i].value == sprite)

			{ heliArrayRemove(&sprites, i); break; }

	for(int i = 0; i < spritesSorted.count; ++i)

		if (spritesSorted.items[i].value == sprite)

			{ heliArrayRemove(&spritesSorted, i); break; }

	free(sprite);

}

void spriteDestroyTimer(Sprite sprite, double lifeTime) {

	if (lifeTime <= 0) { spriteDestroy(sprite); return; }

	sprite->lifeTime = lifeTime;

}

double spriteGetX(Sprite sprite) { return sprite->x; }

void spriteSetX(Sprite sprite, double x) { sprite->x = x; }

double spriteGetY(Sprite sprite) { return sprite->y; }

void spriteSetY(Sprite sprite, double y) { sprite->y = y; }

double spriteGetVelocityX(Sprite sprite) { return sprite->vx; }

void spriteSetVelocityX(Sprite sprite, double x)

	{ spriteSetVelocityXY(sprite, x, sprite->vy); }

double spriteGetVelocityY(Sprite sprite) { return sprite->vy; }

void spriteSetVelocityY(Sprite sprite, double y)

	{ spriteSetVelocityXY(sprite, sprite->vx, y); }

double spriteGetScale(Sprite sprite) { return sprite->scale; }

void spriteSetScale(Sprite sprite, double scale) { sprite->scale = scale; }

double spriteGetWidth(Sprite sprite) { return sprite->width; }

void spriteSetWidth(Sprite sprite, double width)

	{ sprite->width = width > 0 ? width : 0; }

double spriteGetHeight(Sprite sprite) { return sprite->height; }

void spriteSetHeight(Sprite sprite, double height)

	{ sprite->height = height > 0 ? height : 0; }

int spriteGetRotateToDirection(Sprite sprite) { return sprite->rotateToDirection; }

void spriteSetRotateToDirection(Sprite sprite, int rotateToDirection) {

	if (rotateToDirection) {

		sprite->rotateToDirection = TRUE;

		sprite->rotation = spriteGetDirection(sprite);

	} else {

		sprite->rotateToDirection = FALSE;

	}

}

double spriteGetRotation(Sprite sprite) { return sprite->rotation; }

void spriteSetRotation(Sprite sprite, double rotation)

	{ if (!sprite->rotateToDirection) sprite->rotation = rotation; }

double spriteGetRotationSpeed(Sprite sprite) { return sprite->rotationSpeed; }

void spriteSetRotationSpeed(Sprite sprite, double rotationSpeed)

	{ sprite->rotationSpeed = rotationSpeed; }

int spriteGetMirrorX(Sprite sprite) { return sprite->mirrorX; }

void spriteSetMirrorX(Sprite sprite, int mirrorX)

	{ sprite->mirrorX = mirrorX < 0 ? -1 : 1; }

int spriteGetMirrorY(Sprite sprite) { return sprite->mirrorY; }

void spriteSetMirrorY(Sprite sprite, int mirrorY)

	{ sprite->mirrorY = mirrorY < 0 ? -1 : 1; }

double spriteGetDepth(Sprite sprite) { return sprite->depth; }

void spriteSetDepth(Sprite sprite, double depth)

	{ sprite->depth = depth; }

int spriteGetVisible(Sprite sprite) { return sprite->visible; }

void spriteSetVisible(Sprite sprite, int visible)

	{ sprite->visible = visible != FALSE; }

int spriteGetTag(Sprite sprite) { return sprite->tag; }

void spriteSetTag(Sprite sprite, int tag)

	{ sprite->tag = tag; }

int spriteGetDebug(Sprite sprite) { return sprite->debug; }

void spriteSetDebug(Sprite sprite, int debug)

	{ sprite->debug = debug != FALSE; }

int spriteOverlap(Sprite a, Sprite b)

	{ return spriteCollideEx(a, b, TRUE, TRUE, 0); }

int spriteCollide(Sprite a, Sprite b, double bounciness)

	{ return spriteCollideEx(a, b, FALSE, FALSE, bounciness); }

int spriteBounceOff(Sprite sprite, Sprite other, double bounciness)

	{ return spriteCollideEx(sprite, other, FALSE, TRUE, bounciness); }

int spritePush(Sprite sprite, Sprite other, double bounciness)

	{ return spriteCollideEx(sprite, other, TRUE, FALSE, bounciness); }

int spriteCollideEx(Sprite a, Sprite b, int keepVelocityA, int keepVelocityB, double bounciness) {

	if (a == b) return FALSE;

	HeliCollider ca, cb;

	prepareCollider(a, &ca);

	prepareCollider(b, &cb);

	double dx = 0, dy = 0;

	double vx = a->vx - b->vx;

	double vy = a->vy - b->vy;

	bounciness = fabs(bounciness * a->bounciness * b->bounciness);

	if (!heliCheckCollision(&ca, &cb, &dx, &dy, &vx, &vy, bounciness))

		return FALSE;

	if ( keepVelocityA && !keepVelocityB) {

		b->x -= dx;

		b->y -= dy;

		spriteSetVelocityXY(b, a->vx - vx, a->vy - vy);

	} else

	if (!keepVelocityA &&  keepVelocityB) {

		a->x += dx;

		a->y += dy;

		spriteSetVelocityXY(a, b->vx + vx, b->vy + vy);

	} else

	if (!keepVelocityA && !keepVelocityB) {

		double vxAvg = 0.5*(a->vx + b->vx);

		double vyAvg = 0.5*(a->vy + b->vy);

		a->x += 0.5*dx;

		a->y += 0.5*dy;

		spriteSetVelocityXY(a, vxAvg + 0.5*vx, vyAvg + 0.5*vy);

		b->x -= 0.5*dx;

		b->y -= 0.5*dy;

		spriteSetVelocityXY(b, vxAvg - 0.5*vx, vyAvg - 0.5*vy);

	}

	return TRUE;

}

double spriteGetBounciness(Sprite sprite) { return sprite->bounciness; }

void spriteSetBounciness(Sprite sprite, double bounciness)

	{ sprite->bounciness = bounciness > 0 ? bounciness : 0; }

void spriteSetCollider(Sprite sprite, Collider type, double xOffset, double yOffset, double rotationOffset)

	{ spriteSetColliderEx(sprite, type, xOffset, yOffset, rotationOffset, -1, -1, -1); }

void spriteSetColliderCircle(Sprite sprite, double xOffset, double yOffset, double radius)

	{ spriteSetColliderEx(sprite, COLLIDER_CIRCLE, xOffset, yOffset, 0, 0, 0, radius); }

void spriteSetColliderRectangle(

	Sprite sprite, double xOffset, double yOffset, double rotationOffset,

	double width, double height, double cornersRadius )

{

	spriteSetColliderEx(

		sprite, COLLIDER_RECTANGLE,

		xOffset, yOffset, rotationOffset,

		width, height, cornersRadius);

}

void spriteSetColliderEx(

	Sprite sprite, Collider type,

	double xOffset, double yOffset, double rotationOffset,

	double width, double height, double radius )

{

	sprite->collider.type = type;

	sprite->collider.x = xOffset;

	sprite->collider.y = yOffset;

	sprite->collider.rotation = rotationOffset;

	if (type == COLLIDER_CIRCLE) {

		sprite->collider.width = 0;

		sprite->collider.height = 0;

		sprite->collider.radius = radius;

	} else

	if (type == COLLIDER_RECTANGLE) {

		sprite->collider.width = width;

		sprite->collider.height = height;

		sprite->collider.radius = radius;

	} else {

		sprite->collider.width = 0;

		sprite->collider.height = 0;

		sprite->collider.radius = 0;

	}

}

void spriteSetAnimation(Sprite sprite, const char *path) {

	HeliAnimation *prev = sprite->animation;

	sprite->animation = heliAnimationLoad(path);

	if (prev) heliAnimationUnref(prev);

	spriteSetFrame(sprite, sprite->frame);

}

void spriteSetNoAnimation(Sprite sprite) {

	if (sprite->animation) heliAnimationUnref(sprite->animation);

	sprite->animation = NULL;

}

void spritePlay(Sprite sprite) { sprite->playing = TRUE; }

void spritePause(Sprite sprite) { sprite->playing = FALSE; }

void spriteNextFrame(Sprite sprite) { spriteSetFrame(sprite, sprite->frame + 1); }

void spriteSetFrame(Sprite sprite, int frame) {

	sprite->frame = frame >= 0 && sprite->animation && sprite->animation->frames.count > 0

				  ? frame % sprite->animation->frames.count : 0;

}

void spriteSetShapeColor(Sprite sprite, const char *color)

	{ heliParseColor(color, sprite->shapeColor); }

void spriteSetTintColor(Sprite sprite, const char *color)

	{ heliParseColor(color, sprite->tintColor); }

void spriteSetVelocityXY(Sprite sprite, double x, double y) {

	sprite->vx = x;

	sprite->vy = y;

	if (sprite->rotateToDirection)

		sprite->rotation = spriteGetDirection(sprite);

}

void spriteSetSpeedAndDirection(Sprite sprite, double speed, double angle) {

	double a = angle*(PI/180);

	spriteSetVelocityXY(sprite, cos(a)*speed, sin(a)*speed);

}

double spriteGetSpeed(Sprite sprite)

	{ return sqrt(sprite->vx*sprite->vx + sprite->vy*sprite->vy); }

double spriteGetDirection(Sprite sprite) {

	return fabs(sprite->vx) > HELI_PRECISION || fabs(sprite->vy) > HELI_PRECISION

	     ? atan2(sprite->vy, sprite->vx)*(180/PI) : 0;

}

void spritePointTo(Sprite sprite, double x, double y)

	{ spriteSetRotation( sprite, atan2(y - sprite->y, x - sprite->x)*(180/PI) ); }

double spriteGetScaledWidth(Sprite sprite)

	{ return sprite->width * sprite->scale; }

double spriteGetScaledHeight(Sprite sprite)

	{ return sprite->height * sprite->scale; }

int worldGetSpriteCount()

	{ return sprites.count; }

Sprite worldGetSprite(int i)

	{ return (Sprite)heliArrayGetValue(&sprites, i); }

static void drawSpriteDebug(Sprite s) {

	pushDrawingState();

	strokeWeight(0.5);

	double a = s->rotation*(PI/180);

	double sn = sin(a);

	double cs = cos(a);

	double hw = 0.5 * s->scale * s->mirrorX * s->width;

	double hh = 0.5 * s->scale * s->mirrorX * s->height;

	double ltx = -hw*cs + hh*sn;

	double lty = -hw*sn - hh*cs;

	double rtx =  hw*cs + hh*sn;

	double rty =  hw*sn - hh*cs;

	fill("transparent");

	stroke(rgba(0, 0, 0, 0.75));

	// frame

	moveTo(s->x + ltx, s->y + lty);

	lineTo(s->x + rtx, s->y + rty);

	lineTo(s->x - ltx, s->y - lty);

	lineTo(s->x - rtx, s->y - rty);

	closePath();

	// center cross

	line( s->x - cs*hw*0.25, s->y - sn*hw*0.25,

	      s->x + cs*hw*0.25, s->y + sn*hw*0.25 );

	line( s->x + sn*hh*0.25, s->y - cs*hh*0.25,

	      s->x - sn*hh*0.25, s->y + cs*hh*0.25 );

	// depth

	stroke(rgba(0, 0, 0, 0.75));

	char buf[1024];

	snprintf(buf, sizeof(buf)-1, "%lf", s->depth);

	double s1 = hw*0.25;

	double s2 = hh*0.5;

	textSize(s1 < s2 ? s1 : s2);

	textAlign(HALIGN_CENTER, VALIGN_CENTER);

	text(buf, s->x, s->y);

	popDrawingState();

}

static void drawSprite(Sprite s) {

	const double aaBorder = 1;

	unsigned int texid = s->animation

	                   ? (unsigned int)(size_t)heliArrayGetValue(&s->animation->frames, s->frame) : 0u;

	double color[4] = {

		(texid ? 1.0 : s->shapeColor[0])*s->tintColor[0],

		(texid ? 1.0 : s->shapeColor[1])*s->tintColor[1],

		(texid ? 1.0 : s->shapeColor[2])*s->tintColor[2],

		(texid ? 1.0 : s->shapeColor[3])*s->tintColor[3] };

	if (color[3] < HELI_PRECISION) return;

	double w = 0.5*s->scale*s->width;

	double h = 0.5*s->scale*s->height;

	if (w < HELI_PRECISION || h < HELI_PRECISION) return;

	glPushMatrix();

	glTranslated(s->x, s->y, 0);

	glRotated(s->rotation, 0, 0, 1);

	if (aaBorder <= HELI_PRECISION) {

		// use OpenGL multisample antialiasing

		glEnable(GL_MULTISAMPLE);

		const int vcnt = 4;

		const double vertices[][2] = {

			{ -w, -h },

			{  w, -h },

			{ -w,  h },

			{  w,  h } };

		glColor4dv(color);

		if (texid) {

			const double texCoords[][2] = {

				{0, 0},

				{1, 0},

				{0, 1},

				{1, 1} };

			glEnable(GL_TEXTURE_2D);

			glBindTexture(GL_TEXTURE_2D, texid);

			glBegin(GL_TRIANGLE_STRIP);

			for(int i = 0; i < vcnt; ++i) {

				glTexCoord2dv(texCoords[i]);

				glVertex2dv(vertices[i]);

			}

			glEnd();

			glBindTexture(GL_TEXTURE_2D, 0);

			glDisable(GL_TEXTURE_2D);

		} else {

			glBegin(GL_TRIANGLE_STRIP);

			for(int i = 0; i < vcnt; ++i)

				glVertex2dv(vertices[i]);

			glEnd();

		}

		glDisable(GL_MULTISAMPLE);

	} else {

		// make antialiased borde manually

		double sideColor[4] = { color[0], color[1], color[2], 0 };

		double w0 = w - 0.5*aaBorder;

		double w1 = w + 0.5*aaBorder;

		if (w0 < HELI_PRECISION) w0 = 0;

		double h0 = h - 0.5*aaBorder;

		double h1 = h + 0.5*aaBorder;

		if (h0 < HELI_PRECISION) h0 = 0;

		const double k = (w1 < aaBorder ? w1/aaBorder : 1)

		               * (h1 < aaBorder ? h1/aaBorder : 1);

		color[3] *= k;

		w0 *= s->mirrorX;

		w1 *= s->mirrorX;

		h0 *= s->mirrorY;

		h1 *= s->mirrorY;

		const int vcnt = 14;

		const double vertices[][2] = {

			{ -w1, -h1 }, { -w0, -h0 },

			{  w1, -h1 }, {  w0, -h0 },

			{  w1,  h1 }, {  w0,  h0 },

			{ -w1,  h1 }, { -w0,  h0 },

			{ -w1, -h1 }, { -w0, -h0 },

			{ -w0, -h0 },

			{  w0, -h0 },

			{ -w0,  h0 },

			{  w0,  h0 } };

		const double *colors[] = {

			sideColor, color,

			sideColor, color,

			sideColor, color,

			sideColor, color,

			sideColor, color,

			color,

			color,

			color,

			color };

		if (texid) {

			const double tw0 = fabs(w0/w)*0.5 - 0.5;

			const double tw1 = fabs(w1/w)*0.5 - 0.5;

			const double th0 = fabs(h0/h)*0.5 - 0.5;

			const double th1 = fabs(h1/h)*0.5 - 0.5;

			const double texCoords[][2] = {

				{    -tw1,    -th1 }, {    -tw0,    -th0 },

				{ 1 + tw1,    -th1 }, { 1 + tw0,    -th0 },

				{ 1 + tw1, 1 + th1 }, { 1 + tw0, 1 + th0 },

				{    -tw1, 1 + th1 }, {    -tw0, 1 + th0 },

				{    -tw1,    -th1 }, {    -tw0,    -th0 },

				{    -tw0,    -th0 },

				{ 1 + tw0,    -th0 },

				{    -tw0, 1 + th0 },

				{ 1 + tw0, 1 + th0 } };

			glEnable(GL_TEXTURE_2D);

			glBindTexture(GL_TEXTURE_2D, texid);

			glBegin(GL_TRIANGLE_STRIP);

			for(int i = 0; i < vcnt; ++i) {

				glColor4dv(colors[i]);

				glTexCoord2dv(texCoords[i]);

				glVertex2dv(vertices[i]);

			}

			glEnd();

			glBindTexture(GL_TEXTURE_2D, 0);

			glDisable(GL_TEXTURE_2D);

		} else {

			glBegin(GL_TRIANGLE_STRIP);

			for(int i = 0; i < vcnt; ++i) {

				glColor4dv(colors[i]);

				glVertex2dv(vertices[i]);

			}

			glEnd();

		}

	}

	glColor4d(1, 1, 1, 1);

	glPopMatrix();

}

void drawSprites() {

	// sort

	int found = TRUE;

	while(found) {

		found = FALSE;

		// forward

		for(int i = 1; i < spritesSorted.count; ++i) {

			if ( ((Sprite)spritesSorted.items[i-1].value)->depth

			   < ((Sprite)spritesSorted.items[i  ].value)->depth )

			{

				void *x = spritesSorted.items[i].value;

				spritesSorted.items[i].value = spritesSorted.items[i-1].value;

				spritesSorted.items[i-1].value = x;

				found = TRUE;

			}

		}

		if (!found) break;

		// backward

		found = FALSE;

		for(int i = spritesSorted.count - 1; i > 0; --i) {

			if ( ((Sprite)spritesSorted.items[i-1].value)->depth

			   < ((Sprite)spritesSorted.items[i  ].value)->depth )

			{

				void *x = spritesSorted.items[i].value;

				spritesSorted.items[i].value = spritesSorted.items[i-1].value;

				spritesSorted.items[i-1].value = x;

				found = TRUE;

			}

		}

	}

	// draw

	for(int i = 0; i < spritesSorted.count; ++i) {

		Sprite s = (Sprite)(spritesSorted.items[i].value);

		if (s->visible) drawSprite(s);

	}

	// draw debug marks

	for(int i = 0; i < spritesSorted.count; ++i) {

		Sprite s = (Sprite)(spritesSorted.items[i].value);

		if (s->debug) drawSpriteDebug(s);

	}

}

int mouseIsOver(Sprite sprite) {

	HeliCollider collider;

	prepareCollider(sprite, &collider);

	return heliPointCollision(&collider, mouseX(), mouseY());

}

void heliSpriteUpdate(double dt) {

	// auto-remove

	for(int i = sprites.count - 1; i > 0; --i) {

		Sprite s = (Sprite)sprites.items[i].value;

		if (s->lifeTime >= -HELI_PRECISION) {

			s->lifeTime -= dt;

			if (s->lifeTime <= HELI_PRECISION)

				spriteDestroy(s);

		}

	}

	// update

	for(int i = 0; i < sprites.count; ++i) {

		Sprite s = (Sprite)sprites.items[i].value;

		s->x += s->vx*dt;

		s->y += s->vy*dt;

		if (!s->rotateToDirection)

			s->rotation += s->rotationSpeed*dt;

		if (s->playing) spriteNextFrame(s);

	}

}

HeliArray* heliSpriteGetGroups(Sprite sprite)

	{ return &sprite->groups; }

void heliSpriteFinish() {

	while(worldGetSpriteCount())

		{ spriteDestroy(worldGetSprite(0)); }

	heliArrayDestroy(&sprites);

	heliArrayDestroy(&spritesSorted);

}