#include "light.h"
#include "engine.h"
#include "exhumed.h"
#include "view.h"
#include "cd.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#ifdef __WATCOMC__
#include <dos.h>
#include <conio.h>
#include <i86.h>

void handleevents()
{
}
#else

#ifdef __cplusplus
extern "C" {
#endif
int handleevents(void);
#ifdef __cplusplus
}
#endif
#endif

#define kMaxGrads	12

char *GradList[kMaxGrads] = {
	"normal.rmp",
	"nodim.rmp",
	"torch.rmp",
	"notorch.rmp",
	"brite.rmp",
	"redbrite.rmp",
	"grnbrite.rmp",
	"normal.rmp",
	"nodim.rmp",
	"torch.rmp",
	"notorch.rmp",
	"brite.rmp"
};

int rtint = 0;
int gtint = 0;
int btint = 0;
char *origpalookup[kMaxPalookups];
unsigned char curpal[768];
unsigned char kenpal[768];
unsigned char *fadedestpal;
unsigned char *fadecurpal;
short nPalDelay;
short nPalDiff;
short overscanindex;

// keep a local copy of the palette that would have been sent to the VGA display adapter
uchar vgaPalette[768];


void MyLoadPalette()
{
	int hFile = kopen4load("PALETTE.DAT", 1);
	if (hFile == -1)
	{
		printf("Error reading palette 'PALETTE.DAT'\n");
		return;
	}

	kread(hFile, kenpal, sizeof(kenpal));
	kclose(hFile);

	SetOverscan(kenpal);
}

int LoadPaletteLookups()
{
	free(palookup[0]);

	palookup[0] = NULL;
	numpalookups = 64;

	for (int i = 0; i < kMaxGrads; i++)
	{
		int hFile = kopen4load(GradList[i], 1);
		if (hFile == -1)
		{
			printf("Error reading palette lookup '%s'\n", GradList[i]);
			return 0;
		}

		makepalookup(i, NULL, 0, 0, 0, 0);
		kread(hFile, palookup[i], 16384);
		kclose(hFile);

		origpalookup[i] = palookup[i];
	}

	return 1;
}

void SetGreenPal()
{
	for (int i = 0; i < 12; i++)
	{
		palookup[i] = palookup[6];
	}

	palookup[5] = origpalookup[5];
}

void RestoreGreenPal()
{
	for (int i = 0; i < 12; i++)
	{
		palookup[i] = origpalookup[i];
	}
}

void WaitVBL()
{
#ifdef __WATCOMC__
	while (!(inp(0x3da) & 8));
#endif
}

void MySetPalette(unsigned char *palette)
{
	WaitVBL();

#ifdef __WATCOMC__
	outp(0x3C8, 0);

	int i;
	for (i = 0; i < 768; i++)
	{
		outp(0x3C9, *palette);
		palette++;
	}

#else
	// TODO
	kensetpalette(palette);

	memcpy(vgaPalette, palette, sizeof(vgaPalette));
#endif
}

void GetCurPal(unsigned char *palette)
{
#ifdef __WATCOMC__
	if (!palette) {
		palette = curpal;
	}

	outp(0x3C7, 0);

	int i;
	for (i = 0; i < 256; i++)
	{
		*palette = inp(0x3C9);
		palette++;
		*palette = inp(0x3C9);
		palette++;
		*palette = inp(0x3C9);
		palette++;
	}

#else
	if (!palette) {
		memcpy(curpal, vgaPalette, sizeof(curpal));
	}
	else {
		memcpy(palette, vgaPalette, sizeof(curpal));
	}
#endif
}

void GrabPalette()
{
	SetOverscan(kenpal);

	memcpy(curpal, kenpal, sizeof(curpal));

	MySetPalette(kenpal);

	nPalDiff  = 0;
	nPalDelay = 0;

	btint = 0;
	gtint = 0;
	rtint = 0;
}

void BlackOut()
{
	memset(curpal, 0, sizeof(curpal));
	MySetPalette(curpal);
}

void RestorePalette()
{
	memcpy(curpal, kenpal, sizeof(curpal));
	MySetPalette(curpal);
}

void WaitTicks(int nTicks)
{
	if (htimer)
	{
		nTicks += totalclock;
		while (nTicks > totalclock) { handleevents(); }
	}
	else
	{
		while (nTicks > 0) {
			nTicks--;
			WaitVBL();
		}
	}
}

// unused
void DoFadeToRed()
{
	for (int i = 0; i < 256; i += 3)
	{
		if (curpal[i + 1] > 0)
		{
			curpal[i + 1]--;
		}

		if (curpal[i + 2] > 0)
		{
			curpal[i + 1]--;
		}
	}

	MySetPalette(curpal);
}

void FadeToWhite()
{
	int ebx = 0;

	for (int i = 0; i < 64; i++)
	{
		uchar *pPal = curpal;

		for (int j = 0; j < 256; j++)
		{
			for (int k = 0; k < 3; k++)
			{
				if (*pPal < 63)
				{
					(*pPal)++;

					ebx++;
				}

				pPal++;
			}
		}

		MySetPalette(curpal);
		WaitTicks(2);

		// need to page flip in each iteration of the loop for non DOS version
		nextpage();

		if (!ebx) {
			return;
		}
	}
}

void FadeOut(int bFadeMusic)
{
	if (bFadeMusic) {
		StartfadeCDaudio();
	}

	for (int i = 64; i > 0; i--)
	{
		int v4 = 0;

		for (int j = 0; j < 768; j++)
		{
			if (curpal[j] > 0)
			{
				curpal[j]--;
				v4++;
			}
		}

		MySetPalette(curpal);
		WaitTicks(2);

		// need to page flip in each iteration of the loop for non DOS version
		nextpage();

		if (v4 == 0) {
			break;
		}

		if (bFadeMusic) {
			StepFadeCDaudio();
		}
	}

	if (bFadeMusic) {
		while (StepFadeCDaudio() != 0) {}
	}

	EraseScreen(overscanindex);
}

void StartFadeIn()
{
	fadedestpal = kenpal;
	fadecurpal = curpal;
}

int DoFadeIn()
{
	int v2 = 0;

	for (int i = 0; i < 768; i++)
	{
		v2++;

		if (fadecurpal[i] < fadedestpal[i])
		{
			fadecurpal[i]++;
		}

		else
		{
			if (fadecurpal[i] == fadedestpal[i])
			{
				v2--;
			}
			else {
				fadecurpal[i]--;
			}
		}
	}

	MySetPalette(fadecurpal);

	return v2;
}

void FadeIn()
{
	StartFadeIn();

	while (1)
	{
		int val = DoFadeIn();
		WaitTicks(2);

		// need to page flip in each iteration of the loop for non DOS version
		nextpage();

		if (!val) {
			break;
		}
	}
}

void FixPalette()
{
	if (!nPalDiff) {
		return;
	}

	if (nPalDelay > 0)
	{
		nPalDelay--;
		return;
	}

	nPalDelay = 5;

	for (int i = 0; i < 768; i++)
	{
		short nVal = curpal[i] - kenpal[i];
		if (nVal > 0)
		{
			if (nVal > 5)
			{
				curpal[i] -= 5;
			}
			else
			{
				curpal[i] = kenpal[i];
			}
		}
	}

	nPalDiff -= 5;
	gtint -= 5;
	rtint -= 5;

	if (gtint < 0) {
		gtint = 0;
	}

	if (rtint < 0) {
		rtint = 0;
	}

	if (nPalDiff < 0) {
		nPalDiff = 0;
	}

	MySetPalette(curpal);
}

void TintPalette(int r, int g, int b)
{
	int r2 = r;
	int g2 = g;
	int b2 = b;

	uchar *pPal = curpal;

	if (bCamera) {
		return;
	}

	// range limit R between 5 and 63 if positive
	if (r > 63)
	{
		r = 63;
	}
	else
	{
		if (r && r < 5) {
			r = 5;
		}
	}

	// range limit G between 5 and 63 if positive
	if (g > 63)
	{
		g = 63;
	}
	else
	{
		if (g && g < 5) {
			g = 5;
		}
	}

	// range limit B between 5 and 63 if positive
	if (b > 63)
	{
		b = 63;
	}
	else
	{
		if (b && b < 5) {
			b = 5;
		}
	}

	// loc_17EFA
	if (g && gtint > 8) {
		return;
	}

	gtint += g;

	if (r && rtint > 64) {
		return;
	}

	rtint += r;

	// do not modify r, g or b variables from this point on
	r2 = r;
	g2 = g;
	b2 = b;

	if (r2 < 0) {
		r2 = -r2;
	}

	// loc_17F3A
	if (g2 < 0) {
		g2 = -g2;
	}

	int nVal;

	// loc_17F49
	if (r2 > g2) {
		nVal = r;
	}
	else {
		nVal = g;
	}

	if (nVal < 0) {
		nVal = -nVal;
	}

	if (b2 < 0) {
		b2 = -b2;
	}

	if (nVal > b2) {
		nVal = b2;
	}
	else {
		if (b < 0) {
			nVal = -b;
		}
	}

	nPalDiff += nVal;

	for (int i = 0; i < 256; i++)
	{
		*pPal += r;
		if (*pPal > 63) {
			*pPal = 63;
		}

		pPal++;

		*pPal += g;
		if (*pPal > 63) {
			*pPal = 63;
		}

		pPal++;

		*pPal += b;
		if (*pPal > 63) {
			*pPal = 63;
		}

		pPal++;
	}

	nPalDelay = 0;
}

void DoOverscanSet(short someval)
{
#ifdef __WATCOMC__
	union REGS regs;

	regs.h.al = 1;
	regs.h.ah = 0x10;
	regs.h.ch = someval;

	int386(0x10, &regs, &regs);

#endif
}

// unused
void SetWhiteOverscan()
{

}

void SetOverscan(unsigned char *palette)
{
	int edi = 1000;
	overscanindex = 0;

	for (int i = 0; i < 256; i++)
	{
		int ebx = 0;

		for (int j = 0; j < 3; j++)
		{
			uchar cl = *palette;
			palette++;
			ebx += cl;
		}

		if (ebx < edi)
		{
			edi = ebx;
			overscanindex = i;
		}
	}

	DoOverscanSet(overscanindex);
}