todo.c

#include <stdio.h>
#include <stdlib.h>
#include <getopt.h>
#include <string.h>
#include <time.h>
#include <sys/types.h>
#include <regex.h>

#include "todo.h"

const char* colors[] = {"\033[0m", "\033[32m"};

#define MORA_LENGTH 45
const char* mora[] = {"wa", "wi", "wu", "we", "wo",
                      "ra", "ri", "ru", "re", "ro",
                      "ya", "yi", "yu", "ye", "yo",
                      "ma", "mi", "mu", "me", "mo",
                      "ha", "hi", "hu", "he", "ho",
                      "na", "ni", "nu", "ne", "no",
                      "ta", "ti", "tu", "te", "to",
                      "sa", "si", "su", "se", "so",
                      "ka", "ki", "ku", "ke", "ko"};


/* generates an unused id according to the id scheme */
char* generate_id(){
	FILE *fp;
	fp = open_list("r");
	char line[4096]; // todo: define line buffer somewhere
    char* id = malloc(6*sizeof(char));
    int done =0;
    /* we just keep guessing at an unused id until we strike gold.
     * todo: do this in a way that doesn't potentially run forever.
     */
    while(!done){
        sprintf(id, "%s%s\t", mora[rand()%MORA_LENGTH], mora[rand()%MORA_LENGTH]);
        fseek(fp, 0, SEEK_SET);
        done = 1;
        while(fp && fgets(line, sizeof(line), fp)){
            if(strstr(line,id)){
               done = 0; 
            }
        }
    }
	fclose(fp);
    id[5]='\0';
    return id;
}



int main(int argc, char *argv[])
{
	int c;
	unsigned int iseed = (unsigned int)time(NULL);
	srand(iseed);

	if(argc == 1){
		list_all();
		return 0;
	}
	while (1)
	{
		static struct option long_options[] =
		{
			{"help",	no_argument,			NULL,	'h'},
			{"add",     	required_argument,		NULL,	'a'},
			{"show",	required_argument,		NULL,	's'},
			{"done",	required_argument,		NULL,	'd'},
			{"list",	required_argument,		NULL,	'l'},
			{0, 0, 0, 0}
		};
		int option_index = 0;
		c = getopt_long(argc, argv, "ha:s:d:l:", long_options, &option_index);

		if(c == -1)
			break;

		switch(c)
		{

			case 'h':
				help();
			break;

			case 'a':
				add_todo(optarg);
			break;

			case 's':
				list_id(optarg); //todo: fix better casting
			break;

			case 'd':
				remove_todo(optarg); // todo: fix better casting
			break;

			case 'l':
				search(optarg);
			break;
			
		}
	}
	return 0;
}

void help()
{
    printf("Usage:\n");
    printf("todo\n");
    printf("todo (-a|--add) <task>\n");
    printf("todo (-d|--done) <id>\n");
    printf("todo (-s|--show) <id>\n");
    printf("todo (-l|--list) <regex>\n");
}


void add_todo(char string[])
{
    char* id = generate_id();

	FILE *fp;
	fp = open_list("ar");
	fprintf(fp, "%s\t%s\n", id, string);
	fclose(fp);


	printf("Added task with id %s%s%s:\t%s\n",colors[COLOR_GREEN], id, colors[COLOR_RESET], string);
    free(id);
}

void remove_todo(char* id)
{
	FILE *fp;
	char *list_buffer;

	fp = open_list("r");
	fseek(fp, 0L, SEEK_END);
	list_buffer = malloc(ftell(fp)*sizeof(char));
	fseek(fp, 0L, SEEK_SET);

	char line [4096]; // todo: define line buffer somewhere
	while(fgets(line, sizeof(line), fp)){
		if(!strstr(line, id)) {
			if(list_buffer[0] == '\0') {
				sprintf(list_buffer, "%s", line);
			} else {
				sprintf(list_buffer, "%s%s", list_buffer, line);
			}
		} else {
			printf("Removed task ");
            print_line_colored(line);
		}
	}

	fclose(fp);

	fp = open_list("w");
	fprintf(fp, "%s", list_buffer);
	fclose(fp);

	free(list_buffer);
}

void print_line_colored(char*line){
    printf("%s",colors[COLOR_GREEN]);
    int i = 0;
    char c;
    while((c = line[i++]) != '\0'){
        if(c=='\t'){
            printf("%s",colors[COLOR_RESET]);
        }
        printf("%c",c);
    }
}

void list_all()
{
	FILE *fp;
	fp = open_list("r");
	char line[4096]; // todo: define line buffer somewhere
    int counter = 0;
	while(fp && fgets(line, sizeof(line), fp)){
        print_line_colored(line);
        counter++;
	}
    if(!counter){
        printf("No tasks.\n");
        help();
    }
	fclose(fp);
}

// show task with given id. too naive now.
void list_id(char* id)
{
	FILE *fp;
	fp = open_list("r");
	char line[4096]; // todo: define line buffer somewhere
	while(fp && fgets(line, sizeof(line), fp)){
		if(strstr(line,id)){
            print_line_colored(line);
		}
	}

	fclose(fp);
}

FILE *open_list(char *mode)
{
	FILE *fp;
    char todoFilePath[256]; 
    sprintf(todoFilePath,"%s/%s", getenv("HOME"), FILENAME);
	fp = fopen(todoFilePath, mode); 
	if (fp == NULL) {
        fp = fopen(todoFilePath, "w");
        fclose(fp);
        return open_list(mode);
	}
	// file opened properly; return FILE pointer
	return fp;
}

/* search each line in todofile for pattern*/
void search(char string[]) {
    regex_t reg;
    int err;
    char err_msg[80];
	FILE *fp;
    char line[4096];

    if((err = regcomp(&reg, string, REG_NOSUB|REG_EXTENDED)) != 0){
        regerror(err, &reg, err_msg, 80);
        printf("Error analyzing regular expression '%s': %s.\n", string, err_msg);
    }
	fp = open_list("r");
    while(fgets(line, sizeof(line), fp)){
        if(regexec(&reg, line + 4, 0, NULL, 0) == 0)
            print_line_colored(line);
    }
    fclose(fp);
}