Started Rust in Action MEAP.

1 files changed, 181 insertions, 0 deletions

diff --git a/rust-book/employees/src/main.rs b/rust-book/employees/src/main.rs
new file mode 100755
index 0000000..0900bed
--- /dev/null
+++ b/rust-book/employees/src/main.rs
@@ -0,0 +1,181 @@
+use std::collections::HashMap;
+use std::process;
+use std::io::{self, Write};
+
+struct Employees {
+    departments: HashMap<String, Vec<String>>,
+}
+
+impl Employees {
+
+    fn add_employee(&self, name: &Option<&String>, department: &Option<&String>) -> Result<(), &'static str> {
+        // parse name
+        let name = match name {
+            Some(s) => s,
+            None => {
+                return Err("Invalid or empty name.");
+            },
+        };
+
+        // parse department
+        let dept = match department {
+            Some(s) => s,
+            None => {
+                return Err("Invalid or empty department.");
+            },
+        };
+
+        // add name to department in departments
+        // and create department if it doesn't exist
+        employees.entry(dept.to_string())
+            .or_insert(Vec::new())
+            .push(name.to_string());
+
+        Ok(())
+    }
+}
+
+//fn list_employees() {
+//    let dept = match actions.get(1) {
+//        Some(s) => s,
+//        None => {
+//            ""
+//        }
+//    };
+//
+//    if dept == "" {
+//        // print employees in all depts
+//        for each in employees.keys() {
+//            println!("{}", each);
+//            match employees.get(&each.to_string()) {
+//                Some(v) => {
+//                    for every in v {
+//                        println!("  {}", every);
+//                    }
+//                },
+//                None => continue,
+//            };
+//        }
+//    }
+//    else {
+//        // print employees in single dept
+//        match employees.get(&dept.to_string()) {
+//            Some(v) => {
+//                for every in v {
+//                    println!("{}", every);
+//                };
+//            },
+//            None => {
+//                eprintln!("List: Invalid department.");
+//                continue;
+//            }
+//        };
+//    }
+//}
+//
+//fn list_employee(name) {
+//}
+
+
+//fn remove_employee(name) {
+//    let name = match actions.get(1) {
+//        Some(s) => s,
+//        None => {
+//            eprintln!("Remove: Invalid or empty name.");
+//            continue;
+//        },
+//    };
+//
+//    let dept = match actions.get(2) {
+//        Some(s) => s,
+//        None => {
+//            eprintln!("Remove: Empty department.");
+//            continue;
+//        },
+//    };
+//
+//    match employees.get_mut(&dept.to_string()) {
+//        Some(v) => {
+//            v.retain(|employee| employee != name);
+//        },
+//        None => {
+//            eprintln!("Remove: Invalid department.");
+//            continue;
+//        }
+//    };
+
+//}
+
+fn get_actions() -> Vec<String> {
+    print!("> ");
+    io::stdout().flush().unwrap();
+
+    // grab input
+    let mut input = String::new();
+    io::stdin().read_line(&mut input)
+        .expect("Failed to read input.");
+
+    // finish on eof
+    if input == "" {
+        println!("Bye.");
+        process::exit(0);
+    }
+
+    // collect all CLI arguments into vector of trimmed Strings
+    input.trim()
+        .split_whitespace()
+        .map(|action| action.to_string())
+        .collect()
+}
+
+fn main() {
+    println!("Welcome to employee manager.");
+    println!("Enter 'help' for help or Ctrl+D to exit.");
+    let mut departments: HashMap<String, Vec<String>> = HashMap::new();
+
+    // operating loop
+    loop {
+        let actions = get_actions();
+
+        // act on actions
+        let command = match actions.get(0) {
+            Some(c) => c,
+            None => {
+                eprintln!("Empty command. Enter Ctrl+D to exit.");
+                continue;
+            }
+        };
+
+        match command.as_str() {
+            // add employee to department
+            "add" => {
+                match add_employee(&actions.get(1), &actions.get(2), &mut departments) {
+                    Ok(()) => {dbg!(&departments);},
+                    Err(e) => eprintln!("{}", e),
+                };
+            },
+
+            // list employees from one or all departments
+            "list" => {
+            },
+
+            // remove employee from department
+            "remove" => {
+            },
+
+            // print help
+            "help" => {
+                println!("Valid commands include:");
+                println!("\tlist [department]");
+                println!("\tadd <name> <department>");
+                println!("\tremove <name> <department>");
+                println!("Enter 'help' for help or Ctrl+D to exit.");
+            },
+
+            // all else fails
+            _ => eprintln!("Invalid command."),
+        }
+
+    }
+
+}