feat(cli): added a visual branch for the log

src/main.c

@@ -197,7 +197,27 @@ int main(int argc, char** argv) {
                     return 1;
                 }
 
-                ActionList* diff = myers_diff(basefile, modified_file, 0, 0);
+                File* comparison_file = basefile;
+                
+                // If there are previous diffs, we need to compare against the last committed version
+                if (base_file->diff_num > 0) {
+                    size_t prev_diff = base_file->diff_num - 1;
+                    char prev_diff_hash[41];
+                    char id2[2 + snprintf(NULL, 0, "%zu", prev_diff) + strlen(file_name)];
+                    snprintf(id2, sizeof(id2), "%s %zu", file_name, prev_diff);
+                    object_hash(FileDiffObject, id2, prev_diff_hash);
+                    char hash[41];
+                    ActionList* last_diff = parse_object(prev_diff_hash, FileDiffObject, NULL, hash);
+                    if (last_diff) {
+                        File* last_version = apply_diff(basefile, last_diff);
+                        if (last_version) {
+                            comparison_file = last_version;
+                        }
+                        free_action_list(last_diff);
+                    }
+                }
+
+                ActionList* diff = myers_diff(comparison_file, modified_file, 0, 0);
                 if (!diff) {
                     printf("ERROR: unable to compute diff for file %s!\n", file_name);
                     return 1;
@@ -214,6 +234,13 @@ int main(int argc, char** argv) {
                     }
                     string_buffer_push(modified_files, file_name);
                 }
+                
+                free_action_list(diff);
+                free_file(modified_file);
+                if (comparison_file != basefile) {
+                    free_file(comparison_file);
+                }
+                free_file(basefile);
             }
         }
 
@@ -728,13 +755,30 @@ int main(int argc, char** argv) {
 
         read_commit_log(log, log_path);
 
+        char ref_path[PATH_MAX];
+        snprintf(ref_path, sizeof(ref_path), "%s/.merk/refs/branches/%s", root, branch);
+
+        int ref = open(ref_path, O_RDONLY);
+        if (ref < 0) {
+            free(branch);
+            free(root);
+            commit_log_free(log);
+            return -1;
+        }
+        char head[41] = "";
+        read(ref, head, 40);
+        close(ref);
+
         for (size_t i = log->len; i != 0; i--) {
             Commit* commit = (Commit*)log->items + i - 1;
             char human_readable_time[32];
             time_t timestamp = atol(commit->committer.timestamp);
             strftime(human_readable_time, sizeof(human_readable_time), "%Y-%m-%d %H:%M:%S %z", localtime(&timestamp));
 
-            printf("\x1b[33;1m%.7s\x1b[0m: %s\n%s <\x1b[38;5;240m\x1b]8;;mailto:%s\x1b\\%s\x1b]8;;\x1b\\\x1b[0m> (\x1b[36m%s\x1b[0m)\n\n",
+            char* marker = (strcmp(commit->hash, head) == 0) ? "\x1b[32m@\x1b[0m" : "\x1b[34m◯\x1b[0m";
+
+            printf("%s \x1b[33;1m%.7s\x1b[0m: %s\n│ %s <\x1b[38;5;240m\x1b]8;;mailto:%s\x1b\\%s\x1b]8;;\x1b\\\x1b[0m> (\x1b[36m%s\x1b[0m)\n│\n",
+                marker,
                 commit->hash,
                 commit->message,
                 commit->committer.name,
@@ -743,6 +787,7 @@ int main(int argc, char** argv) {
                 human_readable_time
             );
         }
+        if (log->len != 0) printf("┴\n");
 
         free(branch);
         free(root);