#include "config.h"
#include <iostream>
#include <algorithm>
#include <cctype>
#include <string>
#include "hd24fs.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#ifndef WINDOWS
#include <unistd.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <iostream>
#include "convertlib.h"
#define HEADERSIZE 44
#define SAMPLES_IN_HALF_BUF 1024*1024
#define SAMPLES_IN_FULL_BUF 2*SAMPLES_IN_HALF_BUF
#define BYTES_PER_SAM 3
#define BYTES_IN_HALF_BUF BYTES_PER_SAM*SAMPLES_IN_HALF_BUF
#define BYTES_IN_FULL_BUF BYTES_PER_SAM*SAMPLES_IN_FULL_BUF
char audiobuf[BYTES_IN_FULL_BUF];
char fixbuf[BYTES_IN_HALF_BUF];
string inputfile;
string outputfile;
int simple=0;
FILE* infile;
FILE* outfile;
__uint64 writeoffset;

void clearaudiobuf()
{	
	int i;
	for (i=0;i<BYTES_IN_FULL_BUF;i++) {
		audiobuf[i]=0;
	}
}
void shiftaudiobuf()
{
	int i;
	for (i=0;i<BYTES_IN_HALF_BUF;i++) {
		audiobuf[i]=audiobuf[i+BYTES_IN_HALF_BUF];
		audiobuf[i+BYTES_IN_HALF_BUF]=0;
	}
}
int getsam(int samnum)
{	
	int samval=audiobuf[samnum+BYTES_IN_HALF_BUF]
			+(audiobuf[samnum+BYTES_IN_HALF_BUF]*256)
			+(audiobuf[samnum+BYTES_IN_HALF_BUF]*256*256);
	return samval;
}
int tosigned(int samval) {
	if (samval>=(1<<23)) {
			samval-=(1<<24);
	}
	return samval;
}
int topos(int samval) {
	return samval+(1<<23);
}
bool fileexists (string* fname) {
    struct stat fi;
    if ((stat (fname->c_str(), &fi) != -1) && ((fi.st_mode & S_IFDIR) == 0)) {
	return true;
    }
    return false;
}
void hd24seek(FSHANDLE devhd24,__uint64 seekpos) 
{
#if defined(LINUX) || defined(DARWIN)
        lseek(devhd24,seekpos,0);
//	lseek64(devhd24,seekpos,0);
#endif
#ifdef WINDOWS
        LARGE_INTEGER li;
        li.HighPart=seekpos>>32;
        li.LowPart=seekpos%((__uint64)1<<32);
        SetFilePointerEx(devhd24,li,NULL,FILE_BEGIN);
#endif
        return;
}

int parsecommandline(int argc, char ** argv) 
{
	int invalid=0;
	inputfile="";
	outputfile="";
	for (int c=1;c<argc;c++) {
		string arg=argv[c];
		if (arg.substr(0,strlen("--input="))=="--input=") {
			inputfile=arg.substr(strlen("--input="));
			continue;
		}
		if (arg.substr(0,strlen("--output="))=="--output=") {
			outputfile=arg.substr(strlen("--output="));
			continue;
		}
		if (arg.substr(0,strlen("--simple"))=="--simple") {
			simple=1;
			continue;
		}
		cout << "Invalid argument: " << arg << endl;
		invalid=1;
	}
	return invalid;
}
void findmask(FILE* infile)
{
	fseek(infile,HEADERSIZE,SEEK_SET);
	return;
}
void copyheader(FILE* infile,FILE* outfile)
{
	char buffer[HEADERSIZE];
	fseek(infile,0,SEEK_SET);
	int readcount=fread((void*)&buffer[0],1,HEADERSIZE,infile);
	if (readcount>0) {
		int writecount=fwrite((const void*)&buffer[0],1,HEADERSIZE,outfile);
		if (writecount==0) {
			cout << "Cannot write output file" << endl;
		}
	}
	return;
}
void copyaudio(FILE* infile,FILE* outfile) {
	int readcount;
	do {
		shiftaudiobuf();
		readcount=fread((void*)&audiobuf[BYTES_IN_HALF_BUF],1,BYTES_IN_HALF_BUF,infile);
		for (int i=0; i<SAMPLES_IN_HALF_BUF-1;i+=2) {
			int q0=3;
			int q1=0;
			if (audiobuf[BYTES_IN_HALF_BUF+i*3+q0+2-6]==audiobuf[BYTES_IN_HALF_BUF+i*3+q1+2]) {
				audiobuf[BYTES_IN_HALF_BUF+i*3+q0+2]=audiobuf[BYTES_IN_HALF_BUF+i*3+q1+2];
			} else {
			audiobuf[BYTES_IN_HALF_BUF+i*3+q0+0]=audiobuf[BYTES_IN_HALF_BUF+i*3+q1+0];
			audiobuf[BYTES_IN_HALF_BUF+i*3+q0+1]=audiobuf[BYTES_IN_HALF_BUF+i*3+q1+1];
			audiobuf[BYTES_IN_HALF_BUF+i*3+q0+2]=audiobuf[BYTES_IN_HALF_BUF+i*3+q1+2];
			}
		}	
		if (readcount>0) {
			int writecount=fwrite(
					(void*)&audiobuf[BYTES_IN_HALF_BUF],1,readcount,outfile);
			if (writecount==0) {
				cout << "Cannot write output file" << endl;
			}
		}

	}
	while (readcount>0);
	return;
}
void simplecopyaudio(FILE* infile,FILE* outfile)
{
	int readcount;
	do {
		readcount=fread((void*)&audiobuf[BYTES_IN_HALF_BUF],1,BYTES_IN_HALF_BUF,infile);
		for (int i=0; i<SAMPLES_IN_HALF_BUF-1;i+=2) {
			int q0=3;
			int q1=0;
			audiobuf[BYTES_IN_HALF_BUF+i*3+q0+0]=audiobuf[BYTES_IN_HALF_BUF+i*3+q1+0];
			audiobuf[BYTES_IN_HALF_BUF+i*3+q0+1]=audiobuf[BYTES_IN_HALF_BUF+i*3+q1+1];
			audiobuf[BYTES_IN_HALF_BUF+i*3+q0+2]=audiobuf[BYTES_IN_HALF_BUF+i*3+q1+2];
		}	
		if (readcount>0) {
			int writecount=fwrite(
					(void*)&audiobuf[BYTES_IN_HALF_BUF],1,readcount,outfile);
			if (writecount==0) {
				cout << "Cannot write output file" << endl;
			}
		}

	}
	while (readcount>0);
	return;
}
void dothefix(FILE* infile, FILE* outfile)
{
	copyheader(infile,outfile);
	findmask(infile);
	if (simple==1) {
		simplecopyaudio(infile,outfile);
	} else {
		copyaudio(infile,outfile);
	}
}
int main (int argc,char ** argv) 
{
	int invalid=parsecommandline(argc,argv);
	if (invalid!=0) {
		return invalid;
	}
	if ((inputfile=="")||(outputfile=="")) {
		cout << "Usage: hd24wavefix [--simple] --input=<inputfile> --output=<outputfile>" << endl;
		return 1;
	}
	clearaudiobuf();
	// Open files
	infile=fopen(inputfile.c_str(),"rb");
	outfile=fopen(outputfile.c_str(),"wb");
	dothefix(infile,outfile);
	fclose(outfile);
	fclose(infile);
	return 0;	
}