first steps

src/main.rs

@@ -1,3 +1,101 @@
-fn main() {
-    println!("Hello, world!");
+use std::fs;
+use std::fs::File;
+use std::path::PathBuf;
+use std::path::Path;
+use std::io::ErrorKind;
+use std::io::Write;
+use tempfile::NamedTempFile;
+
+const LOCK_FILE: &str = ".mvwrap";
+
+fn read_current_dir() -> Vec<String> {
+    let paths : Vec<PathBuf> = match fs::read_dir(".") {
+        Err(e) if e.kind() == ErrorKind::NotFound => Vec::new(),
+        Err(e) => panic!("Unexpected Error! {:?}", e),
+        Ok(entries) => entries.filter_map(|e| e.ok())
+            .map(|e| e.path())
+            .collect()
+    };
+
+    let mut path_list : Vec<String> = vec![];
+    for path in paths {
+        let path_string = path.display().to_string();
+        if path_string != format!("./{}", LOCK_FILE) {
+            path_list.push(path_string[2..].to_string());
+        }
+    }
+    path_list.sort();
+    path_list
+}
+
+fn lock_dir() {
+    if Path::new(LOCK_FILE).is_file() {
+        panic!("Lock file \"{}\" exists!", LOCK_FILE);
+    }
+    let _file = match File::create(LOCK_FILE) {
+        Ok(file) => file,
+        Err(_) => panic!("Could not create lock file: {}", LOCK_FILE),
+    };
+}
+
+fn unlock_dir() {
+    if Path::new(LOCK_FILE).is_file() {
+        let _result = match fs::remove_file(LOCK_FILE){
+            Ok(result) => result,
+            Err(_) => panic!("Could not remove lock file: {}", LOCK_FILE),
+        };
+    }
+}
+
+fn create_temp_file(paths: Vec<String>) -> String {
+    let mut tmpfile = match NamedTempFile::new(){
+        Ok(file) => file,
+        Err(e) => panic!("Could not create tempfile: {}", e),
+    };
+
+    for path in paths {
+        let _ = writeln!(tmpfile, "{}", path);
+    }
+
+    let filepath = tmpfile.path().display().to_string();
+
+    let _ = match tmpfile.keep(){
+        Ok(res) => res,
+        Err(e) => panic!("Can't keep tempfile: {}", e),
+    };
+
+    filepath
+}
+
+fn remove_temp_file(tmpfile: String) {
+    if Path::new(&tmpfile).is_file() {
+        let _result = match fs::remove_file(&tmpfile){
+            Ok(result) => result,
+            Err(_) => panic!("Could not remove tempfile: {}", &tmpfile),
+        };
+    }
+}
+
+fn main() {
+    lock_dir();
+
+    let paths = read_current_dir();
+
+    // create named tempfile and fill with paths
+    let temp_file = create_temp_file(paths);
+
+    // edit tempfile
+
+    // read and process tempfile
+    println!("In file: {}", temp_file);
+
+    let contents = fs::read_to_string(temp_file.clone())
+        .expect("Should have been able to read the file");
+
+    println!("With text:\n{contents}");
+    println!("----- END ----");
+
+    remove_temp_file(temp_file);
+
+    unlock_dir();
 }