/*
	Read an SQL statement and do a simple pretty print using commas as separator
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <tlmplib.h>
#include <string>

using namespace std;

static bool is_keyword (const char *pt, const char *keyw)
{
	bool ret = false;
	int len = strlen(keyw);
	if (strncasecmp(pt,keyw,len)==0
		&& !isalpha(pt[len]) 
		&& !isdigit(pt[len])
		&& pt[len] != '_'){
		ret = true;
	}
	return ret;
}

static bool indent = false;
static void nextline()
{
	fputc ('\n',stdout);
	if (indent) fputc('\t',stdout);
}

static void format (FILE *fin)
{
	char buf[100000];
	int opnpar = 0;
	while (fgets(buf,sizeof(buf)-1,fin)!=NULL){
		if (strncmp(buf,"***",3)==0){
			printf ("\n%s\n",buf);
			opnpar = 0;
			continue;
		}
		const char *pt = buf;
		int in_function = 0;	// Inside function call, we do not change line at every comma
		bool last_wasalpha = false;	// Last characters (before the open parenthese) were alpha
		while (*pt != '\0'){
			if (is_keyword(pt,"select")
				|| is_keyword(pt,"update")
				|| is_keyword(pt,"create")
				|| is_keyword(pt,"drop")
				|| is_keyword(pt,"insert")){
				nextline();
				for (int i=0; i<opnpar; i++) fputc ('\t',stdout);
				printf ("%-6.6s",pt);
				pt += 6;
			}else if (is_keyword(pt,"into")){
				nextline();
				for (int i=0; i<opnpar; i++) fputc ('\t',stdout);
				printf ("%-4.4s",pt);
				pt+=4;
			}else if (is_keyword(pt,"from")){
				nextline();
				for (int i=0; i<opnpar; i++) fputc ('\t',stdout);
				printf ("%-4.4s",pt);
				pt+=4;
			}else if (is_keyword(pt,"order")){
				nextline();
				for (int i=0; i<opnpar; i++) fputc ('\t',stdout);
				printf ("%-5.5s",pt);
				pt+=5;
			}else if (is_keyword(pt,"group")){
				nextline();
				for (int i=0; i<opnpar; i++) fputc ('\t',stdout);
				printf ("%-5.5s",pt);
				pt+=5;
			}else if (is_keyword(pt,"having")){
				nextline();
				for (int i=0; i<opnpar; i++) fputc ('\t',stdout);
				printf ("%-6.6s",pt);
				pt+=6;
			}else if (is_keyword(pt,"where")){
				nextline();
				for (int i=0; i<opnpar; i++) fputc ('\t',stdout);
				printf ("%-5.5s",pt);
				pt+=5;
			}else if (is_keyword(pt,"union")){
				nextline();
				for (int i=0; i<opnpar; i++) fputc ('\t',stdout);
				printf ("%-5.5s\n",pt);
				pt+=5;
			}else if (isspace(*pt)){
				fputc (' ',stdout);
				while (isspace(*pt)) pt++;
			}else if (isalpha(*pt)){
				while (isalpha(*pt) || *pt == '_') fputc (*pt++,stdout);
				last_wasalpha = true;
			}else if (*pt == '('){
				opnpar++;
				printf ("(");
				pt++;
				if (last_wasalpha) in_function++;
			}else{
				last_wasalpha = false;
				if (*pt == ','){
					if (in_function == 0){
						fputc ('\n',stdout);
						for (int i=0; i<=opnpar; i++) fputc ('\t',stdout);
					}
					fputc (',',stdout);
					pt++;
				}else if (*pt == ')'){
					opnpar--;
					printf (")");
					pt++;
					if (in_function > 0) in_function--;
				}else{
					fputc (*pt,stdout);
					pt++;
				}
			}
		}
		printf ("\n");
	}
}

<mod>
int main (int argc, char *argv[])
{
	glocal int ret = -1;
	glocal.ret = <call tlmpprogram>(argc,argv);
	<f init>
		setproginfo ("formatsql",VERSION,"Format SQL statements");
		setarg ('i',"indent","Indent all the SQL",indent,false);
	</f>
	<f main_noarg>
		format (stdin);
		return 0;
	</f>
	<f main>
		int ret = -1;
		if (argc == 0){
			usage();
		}else{
			for (int i=0; i<argc; i++){
				FILE *fin = fopen (argv[i],"r");
				if (fin == NULL){
					tlmp_error ("Can't open file %s (%s)\n",argv[i],strerror(errno));
					ret = -1;
					break;
				}else{
					ret = 0;
					format (fin);
					fclose (fin);
				}
			}
		}
		return ret;
	</f>
	</call>
	return glocal.ret;
}
</mod>