#include "parseargs.hfa"

// #include <stdio.h>
// #include <stdlib.h>
#include <string.h>
extern "C" {
	#include <getopt.h>

	struct FILE;
	extern FILE * stderr;
	extern FILE * stdout;

	extern int fprintf ( FILE * stream, const char * format, ... );
	extern long long int strtoll (const char* str, char** endptr, int base);
}

void parse_args(
	int argc,
	char * argv[],
	cfa_option options[],
	size_t opt_count,
	const char * usage,
	char ** & left
) {
	struct option optarr[opt_count + 2];
	int width = 0;
	{
		int idx = 0;
		for(i; opt_count) {
			if(options[i].long_name) {
				optarr[idx].name = options[i].long_name;
				optarr[idx].flag = 0p;
				optarr[idx].val  = options[i].short_name;
				if(    ((intptr_t)options[i].parse) == ((intptr_t)parse_settrue)
				    || ((intptr_t)options[i].parse) == ((intptr_t)parse_setfalse) ) {
					optarr[idx].has_arg = no_argument;
				} else {
					optarr[idx].has_arg = required_argument;
				}
				idx++;

				int w = strlen(options[i].long_name);
				if(w > width) width = w;
			}
		}
		optarr[idx+0].[name, has_arg, flag, val] = ["help", no_argument, 0p, 'h'];
		optarr[idx+1].[name, has_arg, flag, val] = [0p, no_argument, 0p, 0];
	}

	char optstring[opt_count * 3] = { '\0' };
	{
		int idx = 0;
		for(i; opt_count) {
			optstring[idx] = options[i].short_name;
			idx++;
			if(    ((intptr_t)options[i].parse) != ((intptr_t)parse_settrue)
			    && ((intptr_t)options[i].parse) != ((intptr_t)parse_setfalse) ) {
				optstring[idx] = ':';
				idx++;
			}
		}
		optstring[idx+0] = 'h';
		optstring[idx+1] = '\0';
	}

	FILE * out = stderr;
	NEXT_ARG:
	for() {
		int idx = 0;
		int opt = getopt_long(argc, argv, optstring, optarr, &idx);
		switch(opt) {
			case -1:
				if(&left != 0p) left = argv + optind;
				return;
			case 'h':
				out = stdout;
			case '?':
				goto USAGE;
			default:
				for(i; opt_count) {
					if(opt == options[i].short_name) {
						const char * arg = optarg ? optarg : "";
						bool success = options[i].parse( arg, options[i].variable );
						if(success) continue NEXT_ARG;

						fprintf(out, "Argument '%s' for option %c could not be parsed\n\n", arg, (char)opt);
						goto USAGE;
					}
				}
				abort("Internal parse arg error\n");
		}

	}

	USAGE:
	fprintf(out, "%s\n", usage);

	for(i; opt_count) {
		fprintf(out, "  -%c, --%-*s   %s\n", options[i].short_name, width, options[i].long_name, options[i].help);
	}
	fprintf(out, "  -%c, --%-*s   %s\n", 'h', width, "help", "print this help message");
	exit(out == stdout ? 0 : 1);
}

bool parse_yesno(const char * arg, bool & value ) {
	if(strcmp(arg, "yes") == 0) {
		value = true;
		return true;
	}

	if(strcmp(arg, "no") == 0) {
		value = false;
		return true;
	}

	return false;
}

bool parse_settrue (const char *, bool & value ) {
	value = true;
	return true;
}

bool parse_setfalse(const char *, bool & value )  {
	value = false;
	return true;
}

bool parse(const char * arg, const char * & value ) {
	value = arg;
	return true;
}

bool parse(const char * arg, int & value) {
	char * end;
	int r = strtoll(arg, &end, 10);
	if(*end != '\0') return false;

	value = r;
	return true;
}