1 files changed, 211 insertions, 0 deletions
diff --git a/src/todo.c b/src/todo.c
new file mode 100644
index 0000000..8d6334f
--- /dev/null
+++ b/src/todo.c
@@ -0,0 +1,211 @@
+/* This file is a part of todo
+ *
+ * Copyright (C) 2021  Robby Zambito
+ *
+ * todo is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * todo is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#define _GNU_SOURCE
+
+#include <errno.h>
+#include <locale.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static FILE *todo_file;
+
+static void puts_strikethrough(char *text) {
+  static const char *strike_overlay = "\u0336";
+  if (text != NULL) {
+    while (*text != '\0') {
+      printf("%s%c", strike_overlay, *text);
+      text++;
+    }
+    puts("");
+  }
+}
+
+static void apply_func_to_line(void (*func)(char *), size_t index) {
+  char *line = NULL;
+  size_t line_len = 0;
+
+  errno = 0;
+  todo_file = fopen("TODO", "r");
+  if (todo_file == NULL) {
+    perror("Could not open the TODO file");
+    exit(EXIT_FAILURE);
+  }
+
+  errno = 0;
+  FILE *temp_file = fopen(".TODO", "w");
+  if (temp_file == NULL) {
+    perror("Could not open temp TODO file");
+    exit(EXIT_FAILURE);
+  }
+
+  for (size_t i = 1; getline(&line, &line_len, todo_file) >= 0; i++) {
+    if (i == index) {
+      func(line);
+    }
+    fprintf(temp_file, "%s", line);
+    free(line);
+  }
+
+  fclose(todo_file);
+  fclose(temp_file);
+
+  // Clobber old TODO with new .TODO
+  rename(".TODO", "TODO");
+}
+
+void todo_list(void) {
+  static const char *bold_text = "\e[1m";
+  static const char *regular_text = "\e[0m";
+
+  char *line = NULL;
+  size_t line_len = 0;
+
+  errno = 0;
+  todo_file = fopen("TODO", "r");
+  if (todo_file == NULL) {
+    if (errno == ENOENT) {
+      // If the file doesn't exist, the list is simply empty
+      exit(EXIT_SUCCESS);
+    } else {
+      perror("Could not open TODO file");
+      exit(EXIT_FAILURE);
+    }
+  }
+
+  for (size_t i = 0; getline(&line, &line_len, todo_file) >= 0; i++) {
+    // Remove trailing newline by setting it to NULL char.
+    line[strcspn(line, "\n")] = '\0';
+
+    if (line_len > 5) {
+      // Print the index in bold
+      printf("%s%zu%s ", bold_text, i + 1, regular_text);
+
+      // Print the task with a strikethrough if completed
+      if (line[1] == ' ') {
+        puts(line + 4);
+      } else if (line[1] == '*') {
+        puts_strikethrough(line + 4);
+      }
+    }
+
+    free(line);
+  }
+
+  fclose(todo_file);
+}
+
+void todo_add(int argc, char **argv) {
+  if (argc < 1) {
+    fprintf(stderr, "todo add takes at least 1 argument\n");
+    exit(EXIT_FAILURE);
+  }
+
+  errno = 0;
+  todo_file = fopen("TODO", "a");
+  if (todo_file == NULL) {
+    perror("Could not open the TODO file");
+    exit(EXIT_FAILURE);
+  }
+
+  for (int i = 0; i < argc; i++) {
+    fprintf(todo_file, "[ ] %s\n", argv[i]);
+  }
+
+  fclose(todo_file);
+}
+
+static void blank(char *task) { task[0] = '\0'; }
+
+void todo_rm(int argc, char **argv) {
+  if (argc < 1) {
+    fprintf(stderr, "todo rm takes at least 1 argument\n");
+    exit(EXIT_FAILURE);
+  }
+
+  size_t remove_index = -1;
+
+  errno = 0;
+  sscanf(argv[0], "%zu", &remove_index);
+  if (errno != 0 || remove_index < 1) {
+    perror("Could not parse index");
+    exit(EXIT_FAILURE);
+  }
+
+  apply_func_to_line(blank, remove_index);
+}
+
+static void done(char *task) { task[1] = '*'; }
+
+void todo_done(int argc, char **argv) {
+  if (argc < 1) {
+    fprintf(stderr, "todo done takes at least 1 argument\n");
+    exit(EXIT_FAILURE);
+  }
+
+  size_t done_index = -1;
+
+  errno = 0;
+  sscanf(argv[0], "%zu", &done_index);
+  if (errno != 0 || done_index < 1) {
+    perror("Could not parse index");
+    exit(EXIT_FAILURE);
+  }
+
+  apply_func_to_line(done, done_index);
+}
+
+void todo_raw(int argc, char **argv) {
+  /*open_todo_file();*/
+  puts("raw");
+  fclose(todo_file);
+}
+
+void todo_sort(void) {
+  /*open_todo_file();*/
+  puts("sort");
+  fclose(todo_file);
+}
+
+void todo_help(void) {
+  puts("Usage: todo [COMMAND] [ARGUMENTS]\n"
+       "Todo is a super fast and simple tasks organizer written in C.\n"
+       "Example: todo list\n"
+       "Available commands:\n"
+       "    - add [TASK/s]\n"
+       "        adds new task/s\n"
+       "        Example: todo add \"buy carrots\"\n"
+       "    - list\n"
+       "        lists all tasks\n"
+       "        Example: todo list\n"
+       "    - done [INDEX]\n"
+       "        marks task as done\n"
+       "        Example: todo done 2 3 (marks second and third tasks as "
+       "completed)\n"
+       "    - rm [INDEX]\n"
+       "        removes a task\n"
+       "        Example: todo rm 4\n"
+       "    - sort\n"
+       "        sorts completed and uncompleted tasks\n"
+       "        Example: todo sort\n"
+       "    - raw [todo/done]\n"
+       "        prints nothing but done/incompleted tasks in plain text, "
+       "useful for scripting\n"
+       "        Example: todo raw done\n");
+}