Prepare more type-safe linking

src/server/web.rs

@@ -1,5 +1,6 @@
 mod admin;
 mod api;
+mod base;
 mod commit;
 mod index;
 mod link;

src/server/web/base.rs

@@ -0,0 +1,46 @@
+use std::fmt;
+
+use crate::config::Config;
+
+pub enum Tab {
+    None,
+    Index,
+    Queue,
+}
+
+#[derive(Clone)]
+pub struct Base {
+    web_base: String,
+    repo_name: String,
+    tab: &'static str,
+}
+
+impl Base {
+    pub fn new(config: &Config, tab: Tab) -> Self {
+        let tab = match tab {
+            Tab::None => "",
+            Tab::Index => "index",
+            Tab::Queue => "queue",
+        };
+        Self {
+            web_base: config.web_base.clone(),
+            repo_name: config.repo_name.clone(),
+            tab,
+        }
+    }
+
+    pub fn link<P: fmt::Display>(&self, to: P) -> Link {
+        let to = format!("{to}");
+        assert!(!self.web_base.ends_with('/'));
+        assert!(to.starts_with('/'));
+        Link(format!("{}{to}", self.web_base))
+    }
+}
+
+pub struct Link(String);
+
+impl fmt::Display for Link {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        self.0.fmt(f)
+    }
+}