/*
	 This file is part of reicast.

	 reicast is free software: you can redistribute it and/or modify
	 it under the terms of the GNU General Public License as published by
	 the Free Software Foundation, either version 2 of the License, or
	 (at your option) any later version.

	 reicast is distributed in the hope that it will be useful,
	 but WITHOUT ANY WARRANTY; without even the implied warranty of
	 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	 GNU General Public License for more details.

	 You should have received a copy of the GNU General Public License
	 along with reicast.  If not, see <https://www.gnu.org/licenses/>.
 */
#include "osd.h"
#include "types.h"
#include "input/gamepad.h"
#include "input/gamepad_device.h"
#include "TexCache.h"

#include <stb_image.h>

#if defined(__ANDROID__)
extern float vjoy_pos[15][8];
#else

static float vjoy_pos[15][8]=
{
	{24+0,24+64,64,64},     //LEFT
	{24+64,24+0,64,64},     //UP
	{24+128,24+64,64,64},   //RIGHT
	{24+64,24+128,64,64},   //DOWN

	{440+0,280+64,64,64},   //X
	{440+64,280+0,64,64},   //Y
	{440+128,280+64,64,64}, //B
	{440+64,280+128,64,64}, //A

	{320-32,360+32,64,64},  //Start

	{440,200,90,64},        //LT
	{542,200,90,64},        //RT

	{-24,128+224,128,128},  //ANALOG_RING
	{96,320,64,64},         //ANALOG_POINT
	{320-32,24,64,64},		// FFORWARD
	{1}						// VJOY_VISIBLE
};
#endif // !__ANDROID__

static const float vjoy_sz[2][15] = {
	{ 64,64,64,64, 64,64,64,64, 64, 90,90, 128, 64, 64 },
	{ 64,64,64,64, 64,64,64,64, 64, 64,64, 128, 64, 64 },
};

static std::vector<OSDVertex> osdVertices;
std::vector<u8> DefaultOSDButtons;

void HideOSD()
{
	vjoy_pos[VJOY_VISIBLE][0] = 0;
}

static void DrawButton(const float xy[8], u32 state)
{
	OSDVertex vtx;

	vtx.r = vtx.g = vtx.b = (0x7F - 0x40 * state / 255) * vjoy_pos[VJOY_VISIBLE][0];
	vtx.a = 0xA0 * vjoy_pos[VJOY_VISIBLE][4];
	vjoy_pos[VJOY_VISIBLE][4] += (vjoy_pos[VJOY_VISIBLE][0] - vjoy_pos[VJOY_VISIBLE][4]) / 2;

	vtx.x = xy[0]; vtx.y = xy[1];
	vtx.u = xy[4]; vtx.v = xy[5];
	osdVertices.push_back(vtx);

	vtx.x = xy[0] + xy[2]; vtx.y = xy[1];
	vtx.u = xy[6]; vtx.v = xy[5];
	osdVertices.push_back(vtx);

	vtx.x = xy[0]; vtx.y = xy[1] + xy[3];
	vtx.u = xy[4]; vtx.v = xy[7];
	osdVertices.push_back(vtx);

	vtx.x = xy[0] + xy[2]; vtx.y = xy[1] + xy[3];
	vtx.u = xy[6]; vtx.v = xy[7];
	osdVertices.push_back(vtx);
}

static void DrawButton2(const float xy[8], bool state)
{
	DrawButton(xy, state ? 0 : 255);
}

const std::vector<OSDVertex>& GetOSDVertices()
{
	osdVertices.reserve(ARRAY_SIZE(vjoy_pos) * 4);
	osdVertices.clear();
	DrawButton2(vjoy_pos[0], kcode[0] & DC_DPAD_LEFT);
	DrawButton2(vjoy_pos[1], kcode[0] & DC_DPAD_UP);
	DrawButton2(vjoy_pos[2], kcode[0] & DC_DPAD_RIGHT);
	DrawButton2(vjoy_pos[3], kcode[0] & DC_DPAD_DOWN);

	DrawButton2(vjoy_pos[4], kcode[0] & DC_BTN_X);
	DrawButton2(vjoy_pos[5], kcode[0] & DC_BTN_Y);
	DrawButton2(vjoy_pos[6], kcode[0] & DC_BTN_B);
	DrawButton2(vjoy_pos[7], kcode[0] & DC_BTN_A);

	DrawButton2(vjoy_pos[8], kcode[0] & DC_BTN_START);

	DrawButton(vjoy_pos[9], lt[0]);

	DrawButton(vjoy_pos[10], rt[0]);

	DrawButton2(vjoy_pos[11], true);
	DrawButton2(vjoy_pos[12], false);

	DrawButton2(vjoy_pos[13], false);

	return osdVertices;
}

static void setVjoyUV()
{
	float u = 0;
	float v = 0;

	for (int i = 0; i < VJOY_VISIBLE; i++)
	{
		//umin, vmin, umax, vmax
		vjoy_pos[i][4] = (u + 1) / OSD_TEX_W;
		vjoy_pos[i][5] = 1.f - (v + 1) / OSD_TEX_H;

		vjoy_pos[i][6] = (u + vjoy_sz[0][i] - 1) / OSD_TEX_W;
		vjoy_pos[i][7] = 1.f - (v + vjoy_sz[1][i] - 1) / OSD_TEX_H;

		u += vjoy_sz[0][i];
		if (u >= OSD_TEX_W)
		{
			u -= OSD_TEX_W;
			v += vjoy_sz[1][i];
		}
	}
}

static OnLoad setVjoyUVOnLoad(&setVjoyUV);

u8 *loadOSDButtons(int &width, int &height)
{
	int n;
	stbi_set_flip_vertically_on_load(1);

	FILE *file = nowide::fopen(get_readonly_data_path("buttons.png").c_str(), "rb");
	u8 *image_data = nullptr;
	if (file != nullptr)
	{
		image_data = stbi_load_from_file(file, &width, &height, &n, STBI_rgb_alpha);
		std::fclose(file);
	}
	if (image_data == nullptr)
	{
		if (DefaultOSDButtons.empty())
			die("No default OSD buttons");
		image_data = stbi_load_from_memory(DefaultOSDButtons.data(), DefaultOSDButtons.size(), &width, &height, &n, STBI_rgb_alpha);
	}
	return image_data;
}