#include <assert.h>
#include <stdio.h>
#include <string.h>

#include "arguments.h"
#include "concurrency.h"

arguments_t* arguments_init(arguments_t* arguments)
{
	assert(arguments);

	arguments->error = 0;
	arguments->help_asked = false;
	arguments->version_asked = false;
	arguments->dir_count = 0;
	arguments->recursive = false;
	arguments->workers = (size_t)concurrency_cpu_count();
	arguments->quiet = false;
	arguments->silent = false;
	arguments->unicode = false;
	arguments->lev_impl = lev_pthreads_guo;

	return arguments;
}

int arguments_print_version(void)
{
	printf("levdist v2.3 [2018-oct-18] Jeisson Hidalgo <jeisson.hidalgo@ucr.ac.cr>\n");
	printf("This is free software with no warranties. Use it at your own risk.\n");

	return 0;
}

int arguments_print_usage(void)
{
	printf("Usage: levdist [-qrsu][-a[dgrs]][-w W] DIRS|FILES\n");
	printf("Finds most similar files using Levenshtein distance\n");
	printf("\n");
	printf("Options:\n");
	printf("      --help                Prints this help\n");
	printf("      --version             Prints information about this command\n");
	printf("  -ad, --pthreads-diagonal  Multi-threaded diagonal comparisons\n");
	printf("  -ag, --pthreads-guo       Multi-threaded (Guo et al. 2013) algorithm\n");
	printf("  -ar, --pthreads-rows      Multi-threaded rows comparisons\n");
	printf("  -as, --serial             Make single-threaded serial comparisons (default)\n");
	printf("  -q, --quiet               Do not print elapsed time (e.g: for testing)\n");
	printf("  -Q, --silent              Do not generate output at all (for testing)\n");
	printf("  -r, --recursive           Analyze files in subdirectories\n");
	printf("  -u, --unicode             Enable Unicode, otherwise ASCII is used\n");
	printf("  -w W                      Use W workers (threads)\n");

	return 0;
}

arguments_t arguments_analyze(int argc, char* argv[])
{
	arguments_t arguments;
	arguments_init(&arguments);

	for ( int current = 1; current < argc; ++current )
	{
		const char* arg = argv[current];

		// Check for an option
		if ( *arg == '-' )
		{
			// Check for a long --argument
			if ( arg[1] == '-' )
			{
				if ( strcmp(arg, "--help") == 0 )
					arguments.help_asked = true;
				if ( strcmp(arg, "--version") == 0 )
					arguments.version_asked = true;
				if ( strcmp(arg, "--recursive") == 0 )
					arguments.recursive = true;
				if ( strcmp(arg, "--quiet") == 0 )
					arguments.quiet = true;
				if ( strcmp(arg, "--silent") == 0 )
					arguments.silent = true;
				if ( strcmp(arg, "--unicode") == 0 )
					arguments.unicode = true;
				if ( strcmp(arg, "--serial") == 0 )
					arguments.lev_impl = lev_serial;
				if ( strcmp(arg, "--pthreads-rows") == 0 )
					arguments.lev_impl = lev_pthreads_byrows;
				if ( strcmp(arg, "--pthreads-guo") == 0 )
					arguments.lev_impl = lev_pthreads_guo;
				if ( strcmp(arg, "--pthreads-diagonal") == 0 )
					arguments.lev_impl = lev_pthreads_diagonal;
			}
			else
			{
				// Short argument provided, e.g: -q
				switch ( arg[1] )
				{
					case 'r': arguments.recursive = true; break;
					case 'q': arguments.quiet = true; break;
					case 'Q': arguments.silent = true; break;
					case 'u': arguments.unicode = true; break;

					case 'a':
					{
						switch ( arg[2] )
						{
							case 'd': arguments.lev_impl = lev_pthreads_diagonal; break;
							case 'g': arguments.lev_impl = lev_pthreads_guo; break;
							case 'r': arguments.lev_impl = lev_pthreads_byrows; break;
							case 's': arguments.lev_impl = lev_serial; break;

							default:
								fprintf(stderr, "levdist: error: unknown Levenshtein implementation: %s\n", arg);
								arguments.error = 4;
						}
						break;
					}

					case 'w':
						if ( current < argc - 1 )
						{
							char* str = argv[++current];
							long workers = 0;
							if ( sscanf(str, "%ld", &workers ) == 1 && workers > 0 )
								arguments.workers = (size_t)workers;
							else
							{
								fprintf(stderr, "levdist: error: invalid number of workers: %s\n", str);
								arguments.error = 2;
							}

							// Avoid considering this argument as a directory later
							*str = '-';
						}
						else
						{
							fprintf(stderr, "levdist: error: missing number of workers\n");
							arguments.error = 3;
						}
						break;

					// Unknown option
					default:
						fprintf(stderr, "levdist: error: unknown argument: %s\n", arg);
						arguments.error = 1;
						break;
				}
			}

		}
		else
		{
			// It is not an option, assume a directory
			++arguments.dir_count;
		}
	}

	return arguments;
}