From 7fdf4514707ff81c2305456b9e54fb358ad0a8e5 Mon Sep 17 00:00:00 2001
From: Edward Shen <code@eddie.sh>
Date: Sun, 27 Sep 2020 17:02:43 -0400
Subject: [PATCH] Use enum for route resolution

---
 src/config.rs | 26 ++++++++++++++++++++++++--
 src/routes.rs | 45 +++++++++++++++++++++++++++++----------------
 2 files changed, 53 insertions(+), 18 deletions(-)

diff --git a/src/config.rs b/src/config.rs
index a4be7fa..791ca74 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -38,6 +38,8 @@ pub struct Route {
   pub path: String,
   pub hidden: bool,
   pub description: Option<String>,
+  pub min_args: Option<usize>,
+  pub max_args: Option<usize>,
 }
 
 impl FromStr for Route {
@@ -48,6 +50,8 @@ impl FromStr for Route {
       path: s.to_string(),
       hidden: false,
       description: None,
+      min_args: None,
+      max_args: None,
     })
   }
 }
@@ -68,6 +72,8 @@ impl<'de> Deserialize<'de> for Route {
       Path,
       Hidden,
       Description,
+      MinArgs,
+      MaxArgs,
     }
 
     struct RouteVisitor;
@@ -83,7 +89,7 @@ impl<'de> Deserialize<'de> for Route {
       where
         E: serde::de::Error,
       {
-        // This is infalliable
+        // This is infallable
         Ok(Self::Value::from_str(path).unwrap())
       }
 
@@ -94,6 +100,8 @@ impl<'de> Deserialize<'de> for Route {
         let mut path = None;
         let mut hidden = None;
         let mut description = None;
+        let mut min_args = None;
+        let mut max_args = None;
 
         while let Some(key) = map.next_key()? {
           match key {
@@ -115,6 +123,18 @@ impl<'de> Deserialize<'de> for Route {
               }
               description = Some(map.next_value()?);
             }
+            Field::MinArgs => {
+              if min_args.is_some() {
+                return Err(de::Error::duplicate_field("min_args"));
+              }
+              min_args = Some(map.next_value()?);
+            }
+            Field::MaxArgs => {
+              if max_args.is_some() {
+                return Err(de::Error::duplicate_field("max_args"));
+              }
+              max_args = Some(map.next_value()?);
+            }
           }
         }
 
@@ -124,6 +144,8 @@ impl<'de> Deserialize<'de> for Route {
           path,
           hidden: hidden.unwrap_or_default(),
           description,
+          min_args,
+          max_args,
         })
       }
     }
@@ -337,7 +359,7 @@ mod route {
   fn serialize() {
     assert_eq!(
       &to_string(&Route::from_str("hello world").unwrap()).unwrap(),
-      "---\nroute_type: External\npath: hello world\nhidden: false\ndescription: ~"
+      "---\nroute_type: External\npath: hello world\nhidden: false\ndescription: ~\nmin_args: ~\nmax_args: ~"
     );
   }
 }
diff --git a/src/routes.rs b/src/routes.rs
index edce7ba..4058aed 100644
--- a/src/routes.rs
+++ b/src/routes.rs
@@ -90,7 +90,7 @@ pub async fn hop(
   let data = data.read().unwrap();
 
   match resolve_hop(&query.to, &data.routes, &data.default_route) {
-    (Some(path), args) => {
+    RouteResolution::Resolved { route: path, args } => {
       let resolved_template = match path {
         ConfigRoute {
           route_type: RouteType::Internal,
@@ -126,10 +126,16 @@ pub async fn hop(
         }
       }
     }
-    (None, _) => HttpResponse::NotFound().body("not found"),
+    RouteResolution::Unresolved => HttpResponse::NotFound().body("not found"),
   }
 }
 
+#[derive(Debug, PartialEq)]
+enum RouteResolution<'a> {
+  Resolved { route: &'a Route, args: String },
+  Unresolved,
+}
+
 /// Attempts to resolve the provided string into its route and its arguments.
 /// If a default route was provided, then this will consider that route before
 /// failing to resolve a route.
@@ -140,21 +146,20 @@ fn resolve_hop<'a>(
   query: &str,
   routes: &'a HashMap<String, Route>,
   default_route: &Option<String>,
-) -> (Option<&'a Route>, String) {
+) -> RouteResolution<'a> {
   let mut split_args = query.split_ascii_whitespace().peekable();
   let command = match split_args.peek() {
     Some(command) => command,
     None => {
       debug!("Found empty query, returning no route.");
-      return (None, String::new());
+      return RouteResolution::Unresolved;
     }
   };
 
   match (routes.get(*command), default_route) {
     // Found a route
-    (Some(resolved), _) => (
-      Some(resolved),
-      match split_args.next() {
+    (Some(resolved), _) => {
+      let args = match split_args.next() {
         // Discard the first result, we found the route using the first arg
         Some(_) => {
           let args = split_args.collect::<Vec<&str>>().join(" ");
@@ -165,21 +170,26 @@ fn resolve_hop<'a>(
           debug!("Resolved {} with no args", resolved);
           String::new()
         }
-      },
-    ),
+      };
+
+      RouteResolution::Resolved {
+        route: resolved,
+        args,
+      }
+    }
     // Unable to find route, but had a default route
     (None, Some(route)) => {
       let args = split_args.collect::<Vec<&str>>().join(" ");
       debug!("Using default route {} with args {}", route, args);
       match routes.get(route) {
-        Some(v) => (Some(v), args),
-        None => (None, String::new()),
+        Some(route) => RouteResolution::Resolved { route, args },
+        None => RouteResolution::Unresolved,
       }
     }
     // No default route and no match
     (None, None) => {
       debug!("Failed to resolve route!");
-      (None, String::new())
+      RouteResolution::Unresolved
     }
   }
 }
@@ -211,15 +221,18 @@ mod resolve_hop {
   fn generate_route_result<'a>(
     keyword: &'a Route,
     args: &str,
-  ) -> (Option<&'a Route>, String) {
-    (Some(keyword), String::from(args))
+  ) -> RouteResolution<'a> {
+    RouteResolution::Resolved {
+      route: keyword,
+      args: String::from(args),
+    }
   }
 
   #[test]
   fn empty_routes_no_default_yields_failed_hop() {
     assert_eq!(
       resolve_hop("hello world", &HashMap::new(), &None),
-      (None, String::new())
+      RouteResolution::Unresolved
     );
   }
 
@@ -231,7 +244,7 @@ mod resolve_hop {
         &HashMap::new(),
         &Some(String::from("google"))
       ),
-      (None, String::new())
+      RouteResolution::Unresolved
     );
   }