update user.rs file and integration in main file

backend/src/user.rs

@@ -0,0 +1,63 @@
+use sqlite::Connection;
+
+pub struct User {
+    name: String,
+    level: u32,
+}
+
+impl User {
+    pub fn open(name: String, level: u32) -> User {
+        User {name, level}
+    }
+
+    pub fn get_name(&self) -> String{return self.name.clone()}
+    pub fn get_level(&self) -> u32{return self.level}
+}
+
+
+pub struct DataBase {
+    connection: Connection,
+}
+
+impl DataBase {
+    pub fn open(name: String) -> DataBase {
+        let connection = sqlite::open(name + ".db").unwrap();
+        DataBase { connection }
+    }
+
+    fn execute(&self, arg: String){
+        match self.connection.execute(arg){
+            _ => (),
+            Err(e) => panic!("Error : {}",e),
+        }
+    }
+
+    pub fn create_table(&self, table: &str, var: &str){
+        self.execute("CREATE TABLE ".to_owned() + &table.to_string() + "(" + &var.to_string() + ");");
+    }
+
+    pub fn add_column(&self, table: &str, arg: &str){
+        self.execute("ALTER TABLE ".to_owned() + &table.to_string() + " ADD " + &arg.to_string() + ";");
+    }
+
+    pub fn insert(&self, table: &str, arg: &str){
+        self.execute("INSERT INTO ".to_owned() + &table.to_string() + " VALUES (" + &arg.to_string() + ")" + ";");
+    }
+
+    pub fn check(&self, table: &str, arg: &str) -> bool {
+    let mut end = false;
+    self.connection.iterate("Select name FROM ".to_owned() + &table.to_string() + " WHERE name = " + &format!("'{}'",&arg.to_string()), |pairs| {
+        for &(name, value) in pairs.iter() {
+            if name == "name" {
+                end = true;
+            }
+        }
+        return end;
+    });   
+    return end;
+    }
+
+    pub fn update(&self, table: &str, arg: &str, where_is: &str, arg2: &str){
+        self.execute("UPDATE ".to_owned() + &table.to_string() + " SET " + &arg.to_string() + " WHERE " + &where_is.to_string() + " = " + &arg2.to_string());
+    }
+}