#include "Core.h"
#if defined CC_BUILD_PSP
#include "_GraphicsBase.h"
#include "Errors.h"
#include "Logger.h"
#include "Window.h"

#include <malloc.h>
#include <pspkernel.h>
#include <pspdisplay.h>
#include <pspdebug.h>
#include <pspctrl.h>
#include <pspgu.h>

#define BUFFER_WIDTH  512
#define SCREEN_WIDTH  480
#define SCREEN_HEIGHT 272

#define FB_SIZE (BUFFER_WIDTH * SCREEN_HEIGHT * 4)
static unsigned int __attribute__((aligned(16))) list[262144];


/*########################################################################################################################*
*---------------------------------------------------------General---------------------------------------------------------*
*#########################################################################################################################*/
static int formatFields[] = {
	GU_TEXTURE_32BITF | GU_VERTEX_32BITF | GU_TRANSFORM_3D,
	GU_TEXTURE_32BITF | GU_COLOR_8888 | GU_VERTEX_32BITF | GU_TRANSFORM_3D
};
static ScePspFMatrix4 identity;

static void guInit(void) {
	void* framebuffer0 = (void*)0;
	void* framebuffer1 = (void*)FB_SIZE;
	void* depthbuffer  = (void*)(FB_SIZE + FB_SIZE);
	Mem_Copy(&identity, &Matrix_Identity, sizeof(ScePspFMatrix4));
	
	sceGuInit();
	sceGuStart(GU_DIRECT, list);
	sceGuDrawBuffer(GU_PSM_8888, framebuffer0, BUFFER_WIDTH);
	sceGuDispBuffer(SCREEN_WIDTH, SCREEN_HEIGHT, framebuffer1, BUFFER_WIDTH);
	sceGuDepthBuffer(depthbuffer, BUFFER_WIDTH);
	
	sceGuOffset(2048 - (SCREEN_WIDTH / 2), 2048 - (SCREEN_HEIGHT / 2));
	sceGuViewport(2048, 2048, SCREEN_WIDTH, SCREEN_HEIGHT);
	sceGuDepthRange(65535,0);
	sceGuFrontFace(GU_CCW);
	sceGuShadeModel(GU_SMOOTH);
	sceGuDisable(GU_TEXTURE_2D);
	
	sceGuAlphaFunc(GU_GREATER, 0x7f, 0xff);
	sceGuBlendFunc(GU_ADD, GU_SRC_ALPHA, GU_ONE_MINUS_SRC_ALPHA, 0, 0);
	sceGuDepthFunc(GU_LEQUAL); // sceGuDepthFunc(GU_GEQUAL);
	sceGuClearDepth(65535); // sceGuClearDepth(0);
	sceGuDepthRange(0, 65535); // sceGuDepthRange(65535, 0);
	
	
	sceGuSetMatrix(GU_MODEL, &identity);
	sceGuColor(0xffffffff);
	sceGuScissor(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT);
	sceGuDisable(GU_SCISSOR_TEST);
	
	sceGuEnable(GU_CLIP_PLANES); // TODO: swap near/far instead of this?
	sceGuTexFunc(GU_TFX_MODULATE, GU_TCC_RGBA);
	
	sceGuFinish();
	sceGuSync(0,0);
	sceDisplayWaitVblankStart();
	sceGuDisplay(GU_TRUE);
}

static GfxResourceID white_square;
void Gfx_Create(void) {
	if (!Gfx.Created) guInit();
	
	Gfx.MaxTexWidth  = 512;
	Gfx.MaxTexHeight = 512;
	Gfx.Created      = true;
	gfx_vsync        = true;
	
	Gfx_RestoreState();
}

void Gfx_Free(void) { 
	Gfx_FreeState();
}

cc_bool Gfx_TryRestoreContext(void) { return true; }

void Gfx_RestoreState(void) {
	InitDefaultResources();
	
	// 1x1 dummy white texture
	struct Bitmap bmp;
	BitmapCol pixels[1] = { BITMAPCOLOR_WHITE };
	Bitmap_Init(bmp, 1, 1, pixels);
	white_square = Gfx_CreateTexture(&bmp, 0, false);
}

void Gfx_FreeState(void) {
	FreeDefaultResources(); 
	Gfx_DeleteTexture(&white_square);
}

#define GU_Toggle(cap) if (enabled) { sceGuEnable(cap); } else { sceGuDisable(cap); }

/*########################################################################################################################*
*---------------------------------------------------------Textures--------------------------------------------------------*
*#########################################################################################################################*/
typedef struct CCTexture_ {
	cc_uint32 width, height;
	cc_uint32 pad1, pad2; // data must be aligned to 16 bytes
	cc_uint32 pixels[];
} CCTexture;

static GfxResourceID Gfx_AllocTexture(struct Bitmap* bmp, int rowWidth, cc_uint8 flags, cc_bool mipmaps) {
	int size = bmp->width * bmp->height * 4;
	CCTexture* tex = (CCTexture*)memalign(16, 16 + size);
	
	tex->width  = bmp->width;
	tex->height = bmp->height;
	CopyTextureData(tex->pixels, bmp->width * 4, bmp, rowWidth << 2);
	return tex;
}

void Gfx_UpdateTexture(GfxResourceID texId, int x, int y, struct Bitmap* part, int rowWidth, cc_bool mipmaps) {
	CCTexture* tex = (CCTexture*)texId;
	cc_uint32* dst = (tex->pixels + x) + y * tex->width;
	CopyTextureData(dst, tex->width * 4, part, rowWidth << 2);
	// TODO: Do line by line and only invalidate the actually changed parts of lines?
	sceKernelDcacheWritebackInvalidateRange(dst, (tex->width * part->height) * 4);
}

/*void Gfx_UpdateTexture(GfxResourceID texId, int x, int y, struct Bitmap* part, int rowWidth, cc_bool mipmaps) {
	CCTexture* tex = (CCTexture*)texId;
	cc_uint32* dst = (tex->pixels + x) + y * tex->width;

	for (int yy = 0; yy < part->height; yy++) {
		Mem_Copy(dst + (y + yy) * tex->width, part->scan0 + yy * rowWidth, part->width * 4);
	}
}*/

void Gfx_DeleteTexture(GfxResourceID* texId) {
	GfxResourceID data = *texId;
	if (data) Mem_Free(data);
	*texId = NULL;
}

void Gfx_EnableMipmaps(void) { }
void Gfx_DisableMipmaps(void) { }

void Gfx_BindTexture(GfxResourceID texId) {
	CCTexture* tex = (CCTexture*)texId;
	if (!tex) tex  = white_square; 
	
	sceGuTexMode(GU_PSM_8888,0,0,0);
	sceGuTexImage(0, tex->width, tex->height, tex->width, tex->pixels);
}


/*########################################################################################################################*
*-----------------------------------------------------State management----------------------------------------------------*
*#########################################################################################################################*/
static PackedCol gfx_clearColor;
void Gfx_SetFaceCulling(cc_bool enabled)   { GU_Toggle(GU_CULL_FACE); }
static void SetAlphaBlend(cc_bool enabled) { GU_Toggle(GU_BLEND); }
void Gfx_SetAlphaArgBlend(cc_bool enabled) { }

void Gfx_ClearColor(PackedCol color) {
	if (color == gfx_clearColor) return;
	sceGuClearColor(color);
	gfx_clearColor = color;
}

static void SetColorWrite(cc_bool r, cc_bool g, cc_bool b, cc_bool a) {
	unsigned int mask = 0xffffffff;
	if (r) mask &= 0xffffff00;
	if (g) mask &= 0xffff00ff;
	if (b) mask &= 0xff00ffff;
	if (a) mask &= 0x00ffffff;
	
	sceGuPixelMask(mask);
}

void Gfx_SetDepthWrite(cc_bool enabled) {
	sceGuDepthMask(enabled ? 0 : 0xffffffff); 
}
void Gfx_SetDepthTest(cc_bool enabled)  { GU_Toggle(GU_DEPTH_TEST); }

/*########################################################################################################################*
*---------------------------------------------------------Matrices--------------------------------------------------------*
*#########################################################################################################################*/
void Gfx_CalcOrthoMatrix(struct Matrix* matrix, float width, float height, float zNear, float zFar) {
	// Transposed, source https://learn.microsoft.com/en-us/windows/win32/opengl/glortho
	//   The simplified calculation below uses: L = 0, R = width, T = 0, B = height
	// NOTE: Shared with OpenGL. might be wrong to do that though?
	*matrix = Matrix_Identity;

	matrix->row1.x =  2.0f / width;
	matrix->row2.y = -2.0f / height;
	matrix->row3.z = -2.0f / (zFar - zNear);

	matrix->row4.x = -1.0f;
	matrix->row4.y =  1.0f;
	matrix->row4.z = -(zFar + zNear) / (zFar - zNear);
}

static float Cotangent(float x) { return Math_CosF(x) / Math_SinF(x); }
void Gfx_CalcPerspectiveMatrix(struct Matrix* matrix, float fov, float aspect, float zFar) {
	float zNear = 0.1f;
	float c = Cotangent(0.5f * fov);

	// Transposed, source https://learn.microsoft.com/en-us/windows/win32/opengl/glfrustum
	// For a FOV based perspective matrix, left/right/top/bottom are calculated as:
	//   left = -c * aspect, right = c * aspect, bottom = -c, top = c
	// Calculations are simplified because of left/right and top/bottom symmetry
	*matrix = Matrix_Identity;

	matrix->row1.x =  c / aspect;
	matrix->row2.y =  c;
	matrix->row3.z = -(zFar + zNear) / (zFar - zNear);
	matrix->row3.w = -1.0f;
	matrix->row4.z = -(2.0f * zFar * zNear) / (zFar - zNear);
	matrix->row4.w =  0.0f;
	// TODO: should direct3d9 one be used insted with clip range from 0,1 ?
}


/*########################################################################################################################*
*-----------------------------------------------------------Misc----------------------------------------------------------*
*#########################################################################################################################*/
static BitmapCol* PSP_GetRow(struct Bitmap* bmp, int y, void* ctx) {
	cc_uint8* fb = (cc_uint8*)ctx;
	return (BitmapCol*)(fb + y * BUFFER_WIDTH * 4);
}

cc_result Gfx_TakeScreenshot(struct Stream* output) {
	int fbWidth, fbFormat;
	void* fb;

	int res = sceDisplayGetFrameBuf(&fb, &fbWidth, &fbFormat, PSP_DISPLAY_SETBUF_NEXTFRAME);
	if (res < 0) return res;
	if (!fb)     return ERR_NOT_SUPPORTED;

	struct Bitmap bmp;
	bmp.scan0  = NULL;
	bmp.width  = SCREEN_WIDTH; 
	bmp.height = SCREEN_HEIGHT;

	return Png_Encode(&bmp, output, PSP_GetRow, false, fb);
}

void Gfx_GetApiInfo(cc_string* info) {
	String_AppendConst(info, "-- Using PSP--\n");
	PrintMaxTextureInfo(info);
}

void Gfx_SetFpsLimit(cc_bool vsync, float minFrameMs) {
	gfx_minFrameMs = minFrameMs;
	gfx_vsync      = vsync;
}

void Gfx_BeginFrame(void) {
	sceGuStart(GU_DIRECT, list);
}

void Gfx_ClearBuffers(GfxBuffers buffers) {
	int targets = 0;
	if (buffers & GFX_BUFFER_COLOR) targets |= GU_COLOR_BUFFER_BIT;
	if (buffers & GFX_BUFFER_DEPTH) targets |= GU_DEPTH_BUFFER_BIT;
	
	sceGuClear(targets);
}

void Gfx_EndFrame(void) {
	sceGuFinish();
	sceGuSync(0, 0);

	if (gfx_vsync) sceDisplayWaitVblankStart();
	sceGuSwapBuffers();
	if (gfx_minFrameMs) LimitFPS();
}

void Gfx_OnWindowResize(void) { }

void Gfx_SetViewport(int x, int y, int w, int h) { }


static cc_uint8* gfx_vertices;
static int gfx_fields;


/*########################################################################################################################*
*----------------------------------------------------------Buffers--------------------------------------------------------*
*#########################################################################################################################*/
static cc_uint16 __attribute__((aligned(16))) gfx_indices[GFX_MAX_INDICES];
static int vb_size;

GfxResourceID Gfx_CreateIb2(int count, Gfx_FillIBFunc fillFunc, void* obj) {
	fillFunc(gfx_indices, count, obj);
}

void Gfx_BindIb(GfxResourceID ib)    { }
void Gfx_DeleteIb(GfxResourceID* ib) { }


static GfxResourceID Gfx_AllocStaticVb(VertexFormat fmt, int count) {
	return memalign(16, count * strideSizes[fmt]);
}

void Gfx_BindVb(GfxResourceID vb) { gfx_vertices = vb; }

void Gfx_DeleteVb(GfxResourceID* vb) {
	GfxResourceID data = *vb;
	if (data) Mem_Free(data);
	*vb = 0;
}

void* Gfx_LockVb(GfxResourceID vb, VertexFormat fmt, int count) {
	vb_size = count * strideSizes[fmt];
	return vb;
}

void Gfx_UnlockVb(GfxResourceID vb) { 
	gfx_vertices = vb; 
	sceKernelDcacheWritebackInvalidateRange(vb, vb_size);
}


static GfxResourceID Gfx_AllocDynamicVb(VertexFormat fmt, int maxVertices) {
	return memalign(16, maxVertices * strideSizes[fmt]);
}

void Gfx_BindDynamicVb(GfxResourceID vb) { Gfx_BindVb(vb); }

void* Gfx_LockDynamicVb(GfxResourceID vb, VertexFormat fmt, int count) {
	vb_size = count * strideSizes[fmt];
	return vb; 
}

void Gfx_UnlockDynamicVb(GfxResourceID vb) { 
	gfx_vertices = vb; 
	sceKernelDcacheWritebackInvalidateRange(vb, vb_size);
}

void Gfx_DeleteDynamicVb(GfxResourceID* vb) { Gfx_DeleteVb(vb); }


/*########################################################################################################################*
*-----------------------------------------------------State management----------------------------------------------------*
*#########################################################################################################################*/
static PackedCol gfx_fogColor;
static float gfx_fogEnd = -1.0f, gfx_fogDensity = -1.0f;
static int gfx_fogMode  = -1;

void Gfx_SetFog(cc_bool enabled) {
	gfx_fogEnabled = enabled;
	//GU_Toggle(GU_FOG);
}

void Gfx_SetFogCol(PackedCol color) {
	if (color == gfx_fogColor) return;
	gfx_fogColor = color;
	//sceGuFog(0.0f, gfx_fogEnd, gfx_fogColor);
}

void Gfx_SetFogDensity(float value) {
}

void Gfx_SetFogEnd(float value) {
	if (value == gfx_fogEnd) return;
	gfx_fogEnd = value;
	//sceGuFog(0.0f, gfx_fogEnd, gfx_fogColor);
}

void Gfx_SetFogMode(FogFunc func) {
	/* TODO: Implemen fake exp/exp2 fog */
}

static void SetAlphaTest(cc_bool enabled) { GU_Toggle(GU_ALPHA_TEST); }

void Gfx_DepthOnlyRendering(cc_bool depthOnly) {
	cc_bool enabled = !depthOnly;
	SetColorWrite(enabled & gfx_colorMask[0], enabled & gfx_colorMask[1], 
				  enabled & gfx_colorMask[2], enabled & gfx_colorMask[3]);
}


/*########################################################################################################################*
*---------------------------------------------------------Matrices--------------------------------------------------------*
*#########################################################################################################################*/
static int matrix_modes[] = { GU_PROJECTION, GU_VIEW };
static ScePspFMatrix4 tmp_matrix; // 16 byte aligned

void Gfx_LoadMatrix(MatrixType type, const struct Matrix* matrix) {
	Mem_Copy(&tmp_matrix, matrix, sizeof(ScePspFMatrix4));
	sceGuSetMatrix(matrix_modes[type], &tmp_matrix);
}

void Gfx_LoadIdentityMatrix(MatrixType type) {
	sceGuSetMatrix(matrix_modes[type], &identity);
}

void Gfx_EnableTextureOffset(float x, float y) {
	sceGuTexOffset(x, y);
}

void Gfx_DisableTextureOffset(void) { 
	sceGuTexOffset(0.0f, 0.0f);
}



/*########################################################################################################################*
*---------------------------------------------------------Drawing---------------------------------------------------------*
*#########################################################################################################################*/
cc_bool Gfx_WarnIfNecessary(void) { return false; }

void Gfx_SetVertexFormat(VertexFormat fmt) {
	if (fmt == gfx_format) return;
	gfx_format = fmt;
	gfx_fields = formatFields[fmt];
	gfx_stride = strideSizes[fmt];

	if (fmt == VERTEX_FORMAT_TEXTURED) {
		sceGuEnable(GU_TEXTURE_2D);
	} else {
		sceGuDisable(GU_TEXTURE_2D);
	}
}

void Gfx_DrawVb_Lines(int verticesCount) {
	sceGuDrawArray(GU_LINES, gfx_fields, verticesCount, NULL, gfx_vertices);
}

void Gfx_DrawVb_IndexedTris_Range(int verticesCount, int startVertex) {
	sceGuDrawArray(GU_TRIANGLES, gfx_fields | GU_INDEX_16BIT, ICOUNT(verticesCount), 
			gfx_indices, gfx_vertices + startVertex * gfx_stride);
}

void Gfx_DrawVb_IndexedTris(int verticesCount) {
	sceGuDrawArray(GU_TRIANGLES, gfx_fields | GU_INDEX_16BIT, ICOUNT(verticesCount),
			gfx_indices, gfx_vertices);
}

void Gfx_DrawIndexedTris_T2fC4b(int verticesCount, int startVertex) {
	sceGuDrawArray(GU_TRIANGLES, gfx_fields | GU_INDEX_16BIT, ICOUNT(verticesCount), 
			gfx_indices, gfx_vertices + startVertex * SIZEOF_VERTEX_TEXTURED);
}
#endif