#include <game.h>

struct HijackedStream {
	//const char *original;
	//const char *originalFast;
	u32 stringOffset;
	u32 stringOffsetFast;
	u8 originalID;
	int streamID;
};

struct Hijacker {
	HijackedStream stream[2];
	u8 currentStream;
	u8 currentCustomTheme;
};



const char* SongNameList [] = {
	"AIRSHIP",
	"BOSS_TOWER",
	"MENU",
	"UNDERWATER",
	"ATHLETIC",
	"CASTLE",
	"MAIN",
	"MOUNTAIN",
	"TOWER",
	"UNDERGROUND",
	"DESERT",
	"FIRE",
	"FOREST",
	"FREEZEFLAME",
	"JAPAN",
	"PUMPKIN",
	"SEWER",
	"SPACE",
	"BOWSER",
	"BONUS",	
	"AMBUSH",	
	"",	
	"SNOW2",	
	"MINIMEGA",	
	"CLIFFS",
	"AUTUMN",
	"CRYSTALCAVES",
	"GHOST_HOUSE",
	"GRAVEYARD",
	"JUNGLE",
	"TROPICAL",
	"SKY_CITY",
	"SNOW",
	"STAR_HAVEN",
	"SINGALONG",
	"FACTORY",
	"TANK",
	"TRAIN",
	"YOSHIHOUSE",
	"FACTORYB",
	"CAVERN",
	"SAND",
	"SHYGUY",
	"MINIGAME",
	"BONUS_AREA",
	"CHALLENGE",
	"",
	"",
	"",
	"",
	"",
	"",
	"",
	"",
	"",
	"",
	"BOSS_CASTLE",
	"BOSS_AIRSHIP",
	"",
	"",
	"",
	"",
	"",
	"",
	"",
	"",
	"",
	NULL	
};



// Offsets are from the start of the INFO block, not the start of the brsar.
// INFO begins at 0x212C0, so that has to be subtracted from absolute offsets
// within the brsar.

#define _I(offs) ((offs)-0x212C0)

Hijacker Hijackers[2] = {
	{
		{
			{/*"athletic_lr.n.32.brstm", "athletic_fast_lr.n.32.brstm",*/ _I(0x4A8F8), _I(0x4A938), 4, STRM_BGM_ATHLETIC},
			{/*"BGM_SIRO.32.brstm", "BGM_SIRO_fast.32.brstm",*/ _I(0x4B2E8), _I(0x4B320), 10, STRM_BGM_SHIRO}
		},
		0, 0
	},

	{
		{
			{/*"STRM_BGM_CHIJOU.brstm", "STRM_BGM_CHIJOU_FAST.brstm",*/ _I(0x4A83C), _I(0x4A8B4), 1, STRM_BGM_CHIJOU},
			{/*"STRM_BGM_CHIKA.brstm", "STRM_BGM_CHIKA_FAST.brstm",*/ _I(0x4A878), _I(0x4A780), 2, STRM_BGM_CHIKA},
		},
		0, 0
	}
};

extern void *SoundRelatedClass;
inline char *BrsarInfoOffset(u32 offset) {
	return (char*)(*(u32*)(((u32)SoundRelatedClass) + 0x5CC)) + offset;
}

void FixFilesize(u32 streamNameOffset);
u8 hijackMusicWithSongName(const char *songName, int themeID, bool hasFast, bool useDrums, int *wantRealStreamID);

extern "C" u8 after_course_getMusicForZone(u8 realThemeID) {
	if (realThemeID < 100)
		return realThemeID;

	bool usesDrums = (realThemeID >= 200);
	return hijackMusicWithSongName(SongNameList[realThemeID-100], realThemeID, true, usesDrums, 0);
}

u8 hijackMusicWithSongName(const char *songName, int themeID, bool hasFast, bool useDrums, int *wantRealStreamID) {
	Hijacker *hj = &Hijackers[useDrums ? 1 : 0];

	// do we already have this theme in this slot?
	// if so, don't switch streams
	// if we do, NSMBW will think it's a different song, and restart it ...
	// but if it's just an area transition where both areas are using the same
	// song, we don't want that
	if ((themeID >= 0) && hj->currentCustomTheme == themeID)
		return hj->stream[hj->currentStream].originalID;

	// which one do we use this time...?
	int toUse = (hj->currentStream + 1) & 1;

	hj->currentStream = toUse;
	hj->currentCustomTheme = themeID;

	// write the stream's info
	HijackedStream *stream = &hj->stream[hj->currentStream];

	sprintf(BrsarInfoOffset(stream->stringOffset), "new/%s.er", songName);
	sprintf(BrsarInfoOffset(stream->stringOffsetFast), hasFast?"new/%s_F.er":"new/%s.er", songName);

	// update filesizes
	FixFilesize(stream->stringOffset);
	FixFilesize(stream->stringOffsetFast);

	// done!
	if (wantRealStreamID)
		*wantRealStreamID = stream->streamID;

	return stream->originalID;
}


//oh for fuck's sake
#include "fileload.h"
//#include <rvl/dvd.h>

void FixFilesize(u32 streamNameOffset) {
	char *streamName = BrsarInfoOffset(streamNameOffset);

	char nameWithSound[80];
	snprintf(nameWithSound, 79, "/Sound/%s", streamName);

	s32 entryNum;
	DVDHandle info;
	
	if ((entryNum = DVDConvertPathToEntrynum(nameWithSound)) >= 0) {
		if (DVDFastOpen(entryNum, &info)) {
			u32 *lengthPtr = (u32*)(streamName - 0x1C);
			*lengthPtr = info.length;
		}
	} else
		OSReport("What, I couldn't find \"%s\" :(\n", nameWithSound);
}