#include <cairo.h>

#include "private.h"

#include "sprite.h"

#include "world.h"

#include "group.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) {

	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);

	return s;

}

Sprite createSprite(double x, double y)

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

void spriteDestroy(Sprite 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(cairo_t *cr, Sprite s) {

	cairo_save(cr);

	cairo_set_line_width(cr, 0.5);

	cairo_translate(cr, s->x, s->y);

	cairo_rotate(cr, s->rotation*(PI/180));

	cairo_scale(cr, s->scale*s->mirrorX, s->scale*s->mirrorY);

	double hw = s->width*0.5;

	double hh = s->height*0.5;

	cairo_set_source_rgba(cr, 0, 0, 0, 0.75);

	cairo_move_to(cr, -hw, -hh);

	cairo_line_to(cr,  hw, -hh);

	cairo_line_to(cr,  hw,  hh);

	cairo_line_to(cr, -hw,  hh);

	cairo_close_path(cr);

	cairo_stroke(cr);

	cairo_move_to(cr, -hw*0.25, 0);

	cairo_line_to(cr,  hw*0.25, 0);

	cairo_move_to(cr, 0, -hh*0.25);

	cairo_line_to(cr, 0,  hh*0.25);

	cairo_stroke(cr);

	char buf[1024];

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

	double s1 = hw*0.25;

	double s2 = hh*0.5;

	cairo_set_font_size(cr, s1 < s2 ? s1 : s2);

	cairo_move_to(cr, -hw*0.9, -hh*0.5);

	cairo_show_text(cr, buf);

	cairo_restore(cr);

}

static void drawSprite(cairo_t *cr, Sprite s) {

	cairo_save(cr);

	cairo_translate(cr, s->x, s->y);

	cairo_rotate(cr, s->rotation*(PI/180));

	cairo_scale(cr, s->scale*s->mirrorX, s->scale*s->mirrorY);

	double hw = s->width*0.5;

	double hh = s->height*0.5;

	cairo_surface_t *frame = s->animation

						   ? (cairo_surface_t*)heliArrayGetValue(&s->animation->frames, s->frame) : NULL;

	double a = s->tintColor[3];

	int tint = fabs(s->tintColor[0] - 1) > HELI_PRECISION

			|| fabs(s->tintColor[1] - 1) > HELI_PRECISION

			|| fabs(s->tintColor[2] - 1) > HELI_PRECISION;

	int alpha = fabs(a) > HELI_PRECISION;

	int visible = fabs(a) > HELI_PRECISION;

	if (visible) {

		if (tint) cairo_push_group(cr);

		if (frame) {

			// image

			double ihw = cairo_image_surface_get_width(frame)*0.5;

			double ihh = cairo_image_surface_get_height(frame)*0.5;

			if (ihw > HELI_PRECISION && ihh > HELI_PRECISION) {

				cairo_save(cr);

				cairo_scale(cr, hw/ihw, hh/ihh);

				cairo_set_source_surface(cr, frame, -ihw, -ihh);

				if (alpha) cairo_paint_with_alpha(cr, a); else cairo_paint(cr);

				cairo_restore(cr);

			}

		} else {

			// rectangle

			cairo_set_source_rgba(cr, s->shapeColor[0], s->shapeColor[1], s->shapeColor[2], s->shapeColor[3]*a);

			cairo_move_to(cr, -hw, -hh);

			cairo_line_to(cr,  hw, -hh);

			cairo_line_to(cr,  hw,  hh);

			cairo_line_to(cr, -hw,  hh);

			cairo_close_path(cr);

			cairo_fill(cr);

		}

		if (tint) {

			cairo_pattern_t *spriteGroup = cairo_pop_group(cr);

			cairo_push_group(cr);

			cairo_set_source(cr, spriteGroup);

			cairo_paint(cr);

			cairo_set_source_rgba(cr, s->tintColor[0], s->tintColor[1], s->tintColor[2], 1);

			cairo_set_operator(cr, CAIRO_OPERATOR_MULTIPLY);

			cairo_mask(cr, spriteGroup);

			cairo_pop_group_to_source(cr);

			cairo_paint(cr);

			cairo_pattern_destroy(spriteGroup);

		}

	}

	cairo_restore(cr);

}

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;

			}

		}

	}

	if (heliCairo) {

		// draw

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

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

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

		}

		// draw debug marks

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

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

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

}