//
// Cforall Version 1.0.0 Copyright (C) 2022 University of Waterloo
//
// The contents of this file are covered under the licence agreement in the
// file "LICENCE" distributed with Cforall.
//
// parseargs.cfa
// implementation of arguments parsing (argc, argv)
//
// Author           : Thierry Delisle
// Created On       : Wed Oct 12 15:28:01 2022
// Last Modified By : Peter A. Buhr
// Last Modified On : Mon Jul  8 18:18:23 2024
// Update Count     : 7
//

#include "parseargs.hfa"

#include <assert.h>
#include <ctype.h>
#include <stdint.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>

extern "C" {
	#include <getopt.h>
	#include <sys/ioctl.h>

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

	extern int fileno( FILE *stream );

	extern int fprintf ( FILE * stream, const char * format, ... );

	extern          long long int strtoll ( const char* str, char** endptr, int base );
	extern unsigned long long int strtoull( const char* str, char** endptr, int base );
	extern                 double strtod  ( const char* str, char** endptr );
}

#include "common.hfa"
#include "limits.hfa"

#pragma GCC visibility push( default )

extern int cfa_args_argc __attribute__(( weak ));
extern char ** cfa_args_argv __attribute__(( weak ));
extern char ** cfa_args_envp __attribute__(( weak ));

forall([N])
static void usage( char * cmd, const array( cfa_option, N ) & options, const char * usage, FILE * out )  __attribute__ (( noreturn ));
//-----------------------------------------------------------------------------
// checking
forall([N])
static void check_args( const array( cfa_option, N ) & options ) {
	for ( i; N ) {
		for ( j; N ) {
			if ( i == j ) continue;

			if ( options[i].short_name != '\0'
			&& options[i].short_name == options[j].short_name )
				abort( "Parse Args error: two options have short name '%c' (%zu & %zu)", options[i].short_name, i, j );

			if (0 == strcmp( options[i].long_name, options[j].long_name ))
				abort( "Parse Args error: two options have long name '%s' (%zu & %zu)", options[i].long_name, i, j );
		}
	}
}


//-----------------------------------------------------------------------------
// Parsing args
forall([opt_count]) {
	void parse_args( const array( cfa_option, opt_count ) & options, const char * usage, char ** & left ) {
		if ( 0p != &cfa_args_argc ) {
			parse_args( cfa_args_argc, cfa_args_argv, options, usage, left );
		} else {
			char * temp[1] = { 0p };
			parse_args(0, temp, options, usage, left );
		}
	}

	void parse_args(
		int argc,
		char * argv[],
		const array( cfa_option, opt_count ) & options,
		const char * usage,
		char ** & left
	) {
		check_args( options );

		int maxv = 'h';
		char optstring[(opt_count * 3) + 2] = { '\0' };
		{
			int idx = 0;
			for ( i; opt_count ) {
				if ( options[i].short_name ) {
					maxv = max( options[i].short_name, maxv );
					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';
		}

		struct option optarr[opt_count + 2];
		{
			int idx = 0;
			for ( i; opt_count ) {
				if ( options[i].long_name ) {
					// we don't have the mutable keyword here, which is really what we would want
					int & val_ref = (int &)(const int &)options[i].val;
					val_ref = (options[i].short_name != '\0') ? ((int)options[i].short_name) : ++maxv;

					optarr[idx].name = options[i].long_name;
					optarr[idx].flag = 0p;
					optarr[idx].val  = options[i].val;
					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++;
				}
			}
			optarr[idx+0].[name, has_arg, flag, val] = ["help", no_argument, 0, 'h'];
			optarr[idx+1].[name, has_arg, flag, val] = [0, no_argument, 0, 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 '?':
					usage( argv[0], options, usage, out );
				default:
					for ( i; opt_count ) {
						if ( opt == options[i].val ) {
							const char * arg = optarg ? optarg : "";
							if ( arg[0] == '=' ) { arg++; }
							// work around for some weird bug
							void * variable = options[i].variable;
							bool (*parse_func)(const char *, void * ) = options[i].parse;
							bool success = parse_func( arg, variable );
							if ( success ) continue NEXT_ARG;

							fprintf( out, "Argument '%s' for option %c could not be parsed\n\n", arg, (char)opt );
							usage( argv[0], options, usage, out );
						}
					}
					abort( "Internal parse arg error\n" );
			}

		}
	}
}

static inline int next_newline( const char * str ) {
	int ret;
	const char * ptr = strstr( str, "\n" );
	if ( ! ptr ) return MAX;

	/* paranoid */ verify( str <= ptr );
	intptr_t low = (intptr_t)str;
	intptr_t hi  = (intptr_t)ptr;
	ret = hi - low;

	return ret;
}

//-----------------------------------------------------------------------------
// Print usage
static void printopt( FILE * out, int width, int max, char sn, const char * ln, const char * help ) {
	// check how wide we should be printing
	// this includes all options and the help message
	int hwidth = max - (11 + width);
	if ( hwidth <= 0 ) hwidth = max;

	// check which pieces we have
	bool has_ln = ln && strcmp( "", ln );
	bool has_help = help && strcmp( "", help );

	// print the small name if present
	if ( sn != '\0') fprintf( out, "  -%c", sn );
	else fprintf( out, "    " );

	// print a comma if we have both short and long names
	if ( sn != '\0' && has_ln ) fprintf( out, ", " );
	else fprintf( out, "  " );

	// print the long name if present
	if ( has_ln ) fprintf( out, "--%-*s", width, ln );
	else if ( has_help ) fprintf( out, "  %-*s", width, "" );

	if ( has_help ) {
		// print the help
		// We need to wrap at the max width, and also indent newlines so everything is nice and pretty

		// for each line to print
		for () {
			//find out if there is a newline
			int nextnl = next_newline( help );
			int real = min( min( strlen( help ), hwidth ), nextnl );

			fprintf( out, "   %.*s", real, help );
			// printf( "%d %d\n", real, nextnl );
			help += real;
			if ( nextnl == real ) help++;
			if ('\0' == *help ) break;
			fprintf( out, "\n%*s", width + 8, "" );
		}
	}
	fprintf( out, "\n" );
}

void print_args_usage( cfa_option options[], const size_t opt_count, const char * usage, bool error )  __attribute__ ((noreturn )) {
	const array( cfa_option, opt_count ) & arr = (const array( cfa_option, opt_count ) &) *options;
	usage( cfa_args_argv[0], arr, usage, error ? stderr : stdout );
}

void print_args_usage( int , char * argv[], cfa_option options[], const size_t opt_count, const char * usage, bool error )  __attribute__ (( noreturn )) {
	const array( cfa_option, opt_count ) & arr = (const array( cfa_option, opt_count ) &) *options;
	usage( argv[0], arr, usage, error ? stderr : stdout );
}

forall( [N] ) {
	void print_args_usage( const array(cfa_option, N ) & options, const char * usage, bool error ) {
		usage( cfa_args_argv[0], options, usage, error ? stderr : stdout );
	}

	void print_args_usage( int argc, char * argv[], const array( cfa_option, N ) & options, const char * usage, bool error ) {
		usage( argv[0], options, usage, error ? stderr : stdout );
	}
}

forall([N])
static void usage( char * cmd, const array( cfa_option, N ) & options, const char * help, FILE * out ) __attribute__(( noreturn )) {
	int width = 0;
	{
		for ( i; N ) {
			if ( options[i].long_name ) {
				int w = strlen( options[i].long_name );
				if ( w > width ) width = w;
			}
		}
	}

	int max_width = 1_000_000;
	int outfd = fileno( out );
	if ( isatty( outfd ) ) {
		struct winsize size;
		int ret = ioctl( outfd, TIOCGWINSZ, &size );
		if ( ret < 0 ) abort( "ioctl error: (%d) %s\n", (int)errno, strerror( errno) );
		max_width = size.ws_col;
	}

	fprintf( out, "Usage:\n  %s %s\n", cmd, help );

	for ( i; N ) {
		printopt( out, width, max_width, options[i].short_name, 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 );
}

//-----------------------------------------------------------------------------
// Typed argument parsing
bool parse_yesno( const char * arg, bool & value ) {
	if ( strcmp( arg, "yes" ) == 0 ) {
		value = true;
		return true;
	}
	if ( strcmp( arg, "Y" ) == 0 ) {
		value = true;
		return true;
	}
	if ( strcmp( arg, "y" ) == 0 ) {
		value = true;
		return true;
	}
	if ( strcmp( arg, "no" ) == 0 ) {
		value = false;
		return true;
	}
	if ( strcmp( arg, "N" ) == 0 ) {
		value = false;
		return true;
	}
	if ( strcmp( arg, "n" ) == 0 ) {
		value = false;
		return true;
	}
	return false;
}

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

	errno = 0;
	long long int r = strtoll( arg, &end, 0 );
	if ( errno ) return false;
	if (*end != '\0') return false;
	if ( r > (int)MAX ) return false;
	if ( r < (int)MIN ) return false;
	value = r;
	return true;
}

static unsigned long long int strict_strtoull( const char * arg, int base ) {
	errno = 0;
	{
		const char * in = arg;
		for () {
			if ( '\0' == *in ) {
				errno = EINVAL;
				return 0;
			}
			if ( ! isspace(*in )) break;
			in++;
		}
		if ( ! isdigit(*in )) {
			errno = EINVAL;
			return 0;
		}
	}
	*char end;
	unsigned long long int r = strtoull( arg, &end, base );
	if (*end != '\0') errno = EINVAL;
	if ( errno ) return 0;
	return r;
}

bool parse( const char * arg, unsigned & value ) {
	unsigned long long int r = strict_strtoull( arg, 0 );
	if ( errno ) return false;
	if ( r > (unsigned)MAX ) return false;
	value = r;
	return true;
}

bool parse( const char * arg, unsigned long & value ) {
	unsigned long long int r = strict_strtoull( arg, 0 );
	if ( errno ) return false;
	if ( r > (unsigned long)MAX ) return false;
	value = r;
	return true;
}

bool parse( const char * arg, unsigned long long & value ) {
	unsigned long long int r = strict_strtoull( arg, 0 );
	if ( errno ) return false;
	if ( r > (unsigned long long)MAX ) return false;
	value = r;
	return true;
}

bool parse( const char * arg, double & value ) {
	char * end;
	double r = strtod( arg, &end );
	if ( *end != '\0') return false;
	value = r;
	return true;
}