cli/show: add possibility to copy the task part

Closes #22

src/cli/show.rs

@@ -13,12 +13,18 @@
 //! You should have received a copy of the GNU General Public License
 //! along with tas.  If not, see <https://www.gnu.org/licenses/>.
 //!
+use std::io::Write;
+use std::process::{Command, Stdio};
+
 use crate::cli::print_task_detail;
 use crate::domain::CurrentTaskInfo;
 use crate::repo::Repository;
 
 #[derive(clap::Args)]
 pub struct Args {
+    #[clap(short, long)]
+    clip: bool,
+
     part: Option<PrintPart>,
 }
 
@@ -55,26 +61,57 @@ pub fn execute(repo: impl Repository, args: Args) {
 
     match args.part {
         None => {
+            if args.clip {
+                eprintln!("[WARNING]: You don't provide part. --clip option will ignore.");
+            }
+
             println!("Information about your current task:");
             print_task_detail(&task);
         }
         Some(PrintPart::Project) => {
-            println!("{}", task.project.unwrap_or_else(|| String::from('-')))
+            if args.clip {
+                if let Some(project) = task.project {
+                    save_to_clipboard(&project);
+                } else {
+                    eprintln!("Task doesn't contain a project");
+                }
+            } else {
+                println!("{}", task.project.unwrap_or_else(|| String::from('-')))
+            }
         }
         Some(PrintPart::DirPath) => {
-            println!(
-                "{}",
-                task.dir_path
-                    .unwrap_or_else(|| std::env::current_dir().expect("Cannot get current dir"))
-                    .to_string_lossy()
-            )
+            let dir_path = task
+                .dir_path
+                .unwrap_or_else(|| std::env::current_dir().expect("Cannot get current dir"));
+            if args.clip {
+                save_to_clipboard(&dir_path.to_string_lossy())
+            } else {
+                println!("{}", dir_path.to_string_lossy())
+            }
         }
         Some(PrintPart::Link) => {
             if let Some(link) = task.link {
-                println!("{}", link)
+                if args.clip {
+                    save_to_clipboard(&link);
+                } else {
+                    println!("{}", link)
+                }
             } else {
                 eprintln!("The current task doesn't contain link")
             }
         }
     }
 }
+
+fn save_to_clipboard(input: &str) {
+    let xclip_cmd = Command::new("xclip")
+        .args(["-sel", "clip"])
+        .stdin(Stdio::piped())
+        .spawn()
+        .expect("Cannot spawn xclip command");
+
+    let mut xclip_stdin = xclip_cmd.stdin.expect("Cannot get stdin for xclip command");
+    xclip_stdin
+        .write_all(input.as_bytes())
+        .expect("Cannot save data to the clipboard");
+}