Add evaluate function to plugins

This allows plugins to be used in combination with each other.

6 files changed, 79 insertions, 45 deletions

diff --git a/src/plugin.rs b/src/plugin.rs
index d14c129..63d3530 100644
--- a/src/plugin.rs
+++ b/src/plugin.rs
@@ -13,6 +13,8 @@ pub trait Plugin: PluginName + Send + Sync + fmt::Debug {
     fn execute(&self, server: &IrcServer, message: &Message) -> Result<(), IrcError>;
     /// Handles any command directed at this plugin.
     fn command(&self, server: &IrcServer, command: PluginCommand) -> Result<(), IrcError>;
+    /// Should work like command but return a String instead of sending messages to IRC.
+    fn evaluate(&self, server: &IrcServer, command: PluginCommand) -> Result<String, String>;
 }
 
 /// `PluginName` is required by `Plugin`.  
diff --git a/src/plugins/currency.rs b/src/plugins/currency.rs
index 634faa2..4d44d9a 100644
--- a/src/plugins/currency.rs
+++ b/src/plugins/currency.rs
@@ -68,24 +68,26 @@ impl Currency {
         Currency {}
     }
 
-    fn eval_command<'a>(&self, tokens: &'a [String]) -> Result<ConvertionRequest<'a>, ParseFloatError> {
+    fn eval_command<'a>(&self,
+                        tokens: &'a [String])
+                        -> Result<ConvertionRequest<'a>, ParseFloatError> {
         Ok(ConvertionRequest {
-            value: tokens[0].parse()?,
-            source: &tokens[1],
-            target: &tokens[2],
-        })
+               value: tokens[0].parse()?,
+               source: &tokens[1],
+               target: &tokens[2],
+           })
     }
 
-    fn convert(&self, server: &IrcServer, command: PluginCommand) -> Result<(), IrcError> {
+    fn convert(&self, server: &IrcServer, command: &mut PluginCommand) -> Result<String, String> {
 
         if command.tokens.len() < 3 {
-            return self.invalid_command(server, &command);
+            return Err(self.invalid_command(server));
         }
 
         let request = match self.eval_command(&command.tokens) {
             Ok(request) => request,
             Err(_) => {
-                return self.invalid_command(server, &command);
+                return Err(self.invalid_command(server));
             }
         };
 
@@ -97,31 +99,27 @@ impl Currency {
                                        response / 1.00000000,
                                        request.target.to_lowercase());
 
-                server.send_privmsg(&command.target, &response)
+                Ok(response)
             }
-            None => server.send_notice(&command.source, "Error while converting given currency"),
+            None => Err(String::from("An error occured during the conversion of the given currency")),
         }
     }
 
-    fn help(&self, server: &IrcServer, command: &mut PluginCommand) -> Result<(), IrcError> {
-        let help = format!("usage: {} currency value from_currency to_currency\r\n\
+    fn help(&self, server: &IrcServer) -> String {
+        format!("usage: {} currency value from_currency to_currency\r\n\
                             example: 1.5 eur usd\r\n\
                             available currencies: AUD, BGN, BRL, CAD, \
                             CHF, CNY, CZK, DKK, GBP, HKD, HRK, HUF, \
                             IDR, ILS, INR, JPY, KRW, MXN, MYR, NOK, \
                             NZD, PHP, PLN, RON, RUB, SEK, SGD, THB, \
                             TRY, USD, ZAR",
-                           server.current_nickname());
-
-        server.send_notice(&command.source, &help)
+                           server.current_nickname())
     }
 
-    fn invalid_command(&self, server: &IrcServer, command: &PluginCommand) -> Result<(), IrcError> {
-        let help = format!("Incorrect Command. \
+    fn invalid_command(&self, server: &IrcServer) -> String {
+        format!("Incorrect Command. \
                            Send \"{} currency help\" for help.",
-                           server.current_nickname());
-
-        server.send_notice(&command.source, &help)
+                   server.current_nickname())
     }
 }
 
@@ -137,12 +135,26 @@ impl Plugin for Currency {
     fn command(&self, server: &IrcServer, mut command: PluginCommand) -> Result<(), IrcError> {
 
         if command.tokens.is_empty() {
-            return self.invalid_command(server, &command);
+            return server.send_notice(&command.source, &self.invalid_command(server));
+        }
+
+        match command.tokens[0].as_ref() {
+            "help" => server.send_notice(&command.source, &self.help(server)),
+            _ => match self.convert(server, &mut command) {
+                Ok(msg) => server.send_privmsg(&command.target, &msg),
+                Err(msg) => server.send_notice(&command.source, &msg),
+            }
+        }
+    }
+
+    fn evaluate(&self, server: &IrcServer, mut command: PluginCommand) -> Result<String, String>{
+        if command.tokens.is_empty() {
+            return Err(self.invalid_command(server));
         }
 
         match command.tokens[0].as_ref() {
-            "help" => self.help(server, &mut command),
-            _ => self.convert(server, command),
+            "help" => Ok(self.help(server)),
+            _ => self.convert(server, &mut command),
         }
     }
 }
diff --git a/src/plugins/emoji.rs b/src/plugins/emoji.rs
index 59e2fdd..512a62e 100644
--- a/src/plugins/emoji.rs
+++ b/src/plugins/emoji.rs
@@ -36,13 +36,12 @@ impl Emoji {
         Emoji {}
     }
 
-    fn emoji(&self, server: &IrcServer, content: &str, target: &str) -> Result<(), IrcError> {
-        let names = self.return_emojis(content)
+    fn emoji(&self, content: &str) -> String {
+        self.return_emojis(content)
             .iter()
             .map(|e| e.to_string())
-            .collect::<Vec<String>>();
-
-        server.send_privmsg(target, &names.join(", "))
+            .collect::<Vec<String>>()
+            .join(", ")
     }
 
     fn return_emojis(&self, string: &str) -> Vec<EmojiHandle> {
@@ -108,7 +107,8 @@ impl Plugin for Emoji {
     fn execute(&self, server: &IrcServer, message: &Message) -> Result<(), IrcError> {
         match message.command {
             Command::PRIVMSG(_, ref content) => {
-                self.emoji(server, content, message.response_target().unwrap())
+                server.send_privmsg(message.response_target().unwrap(),
+                                    &self.emoji(content))
             }
             _ => Ok(()),
         }
@@ -118,6 +118,15 @@ impl Plugin for Emoji {
         server.send_notice(&command.source,
                            "This Plugin does not implement any commands.")
     }
+
+    fn evaluate(&self, _: &IrcServer, command: PluginCommand) -> Result<String, String> {
+        let emojis = self.emoji(&command.tokens[0]);
+        if emojis.is_empty() {
+            Ok(emojis)
+        } else {
+            Err(String::from("No emojis were found."))
+        }
+    }
 }
 
 #[cfg(test)]
diff --git a/src/plugins/help.rs b/src/plugins/help.rs
index 7b987d4..cea325f 100644
--- a/src/plugins/help.rs
+++ b/src/plugins/help.rs
@@ -10,10 +10,6 @@ impl Help {
     pub fn new() -> Help {
         Help {}
     }
-
-    fn help(&self, server: &IrcServer, command: PluginCommand) -> Result<(), IrcError> {
-        server.send_notice(&command.source, "Help has not been added yet.")
-    }
 }
 
 impl Plugin for Help {
@@ -26,7 +22,11 @@ impl Plugin for Help {
     }
 
     fn command(&self, server: &IrcServer, command: PluginCommand) -> Result<(), IrcError> {
-        self.help(server, command)
+        server.send_notice(&command.source, "Help has not been added yet.")
+    }
+
+    fn evaluate(&self, _: &IrcServer, _: PluginCommand) -> Result<String, String> {
+        Err(String::from("Help has not been added yet."))
     }
 }
 
diff --git a/src/plugins/keepnick.rs b/src/plugins/keepnick.rs
index 1d4627d..2970857 100644
--- a/src/plugins/keepnick.rs
+++ b/src/plugins/keepnick.rs
@@ -54,6 +54,10 @@ impl Plugin for KeepNick {
         server.send_notice(&command.source,
                            "This Plugin does not implement any commands.")
     }
+
+    fn evaluate(&self, _: &IrcServer, _: PluginCommand) -> Result<String, String> {
+        Err(String::from("This Plugin does not implement any commands."))
+    }
 }
 
 #[cfg(test)]
diff --git a/src/plugins/url.rs b/src/plugins/url.rs
index f6e06f3..ab36833 100644
--- a/src/plugins/url.rs
+++ b/src/plugins/url.rs
@@ -95,11 +95,11 @@ impl Url {
         }
     }
 
-    fn url(&self, server: &IrcServer, message: &str, target: &str) -> Result<(), IrcError> {
-        let url = match self.grep_url(message) {
+    fn url(&self, text: &str) -> Result<String, &str> {
+        let url = match self.grep_url(text) {
             Some(url) => url,
             None => {
-                return Ok(());
+                return Err("No Url was found.")
             }
         };
 
@@ -109,18 +109,18 @@ impl Url {
 
                 let doc = Document::from(body.as_ref());
                 if let Some(title) = doc.find(Name("title")).next() {
-                    let text = title.children().next().unwrap();
-                    let message = text.as_text().unwrap().trim().replace("\n", "|");
-                    debug!("Title: {:?}", text);
-                    debug!("Message: {:?}", message);
+                    let title = title.children().next().unwrap();
+                    let title_text = title.as_text().unwrap().trim().replace("\n", "|");
+                    debug!("Title: {:?}", title);
+                    debug!("Text: {:?}", title_text);
 
-                    server.send_privmsg(target, &message)
+                    Ok(title_text)
 
                 } else {
-                    Ok(())
+                    Err("No title was found.")
                 }
             }
-            None => Ok(()),
+            None => Err("Failed to download document.")
         }
     }
 }
@@ -136,7 +136,10 @@ impl Plugin for Url {
     fn execute(&self, server: &IrcServer, message: &Message) -> Result<(), IrcError> {
         match message.command {
             Command::PRIVMSG(_, ref content) => {
-                self.url(server, content, message.response_target().unwrap())
+                match self.url(content) {
+                    Ok(title) => server.send_privmsg(&message.response_target().unwrap(), &title),
+                    Err(_) => Ok(()),
+                }
             }
             _ => Ok(()),
         }
@@ -146,6 +149,10 @@ impl Plugin for Url {
         server.send_notice(&command.source,
                            "This Plugin does not implement any commands.")
     }
+
+    fn evaluate(&self, _: &IrcServer, command: PluginCommand) -> Result<String, String> {
+        self.url(&command.tokens[0]).map_err(|e| String::from(e))
+    }
 }
 
 #[cfg(test)]