Serializing & processing server messages

Now received output is translated into grokkable alists.

ircc.scm

@@ -16,15 +16,20 @@
 ;;
 
 
-(import srfi-1 openssl (chicken tcp) (chicken io))
+(import scheme
+		(chicken io) (chicken tcp)
+		srfi-1 srfi-69 srfi-130
+		openssl)
 
 
 ;; Connect to the given IRC server, returning an IRC connection object.
 (define (irc:connect host port username nick #!optional (password #f) (realname #f))
-  (define-values (out in)
-	(ssl-connect* hostname: host port: port))
+  (let ([conn (make-hash-table)])
+	(define-values (out in)
+	  (ssl-connect* hostname: host port: port))
+	(hash-table-set! conn 'in in)
+	(hash-table-set! conn 'out out)
 
-  (let ([conn (list out in)])
 	(if password
 		(irc:write-cmd conn "PASS" password))
 	(irc:write-cmd conn "USER" username "*" "0"
@@ -33,14 +38,66 @@
 	conn))
 
 
+;; Join the given channel. Not much to say, really.
+(define (irc:join conn channel #!optional key)
+  (let* ([params-sans-key (list conn "JOIN" channel)]
+		 [params (if key (append params-sans-key `(,key))
+					 params-sans-key)])
+		(apply irc:write-cmd params)))
+
+
+;; Read-in the next reply or command from the server, into a parsable alist with
+;; four keys:
+(define (irc:read-alist conn)
+  (irc:process-alist-internally
+   conn
+   (irc:line->alist
+	(read-line (hash-table-ref conn 'out)))))
+
+
+(define (irc:read-line conn)
+  (read-line (hash-table-ref conn 'out)))
+
+
 ;; Send a specific command to the server.
 (define (irc:write-cmd conn command . parameters)
-  (irc:write-line (apply irc:cmd (append `(,command) parameters))
+  (irc:write-line (apply irc:cmd->string (append `(,command) parameters))
 				  conn))
 
 
+;; Write a line to the IRC server connection.
+(define (irc:write-line text connection)
+  (write-line text (hash-table-ref connection 'in)))
+
+
+;; The user should have more-or-less total control over how to respond to
+;; received messages, but ircc has to sneakily process some responses itself,
+;; to ensure basic functionality (i.e., pings, chanlist, userlist, etc.)
+(define (irc:process-alist-internally conn alist)
+  (let ([command (alist-car-ref 'command alist)]
+		[reply (alist-car-ref 'reply alist)]
+		[sender (alist-car-ref 'sender alist)]
+		[params (alist-ref 'params alist)])
+	(if command
+		(irc:process-command-internally conn command params sender)
+		(irc:process-reply-internally conn reply params sender)))
+  alist)
+
+
+;; Handle some replies necssary for basic functionality
+(define (irc:process-reply-internally conn reply params #!optional sender)
+  (cond [(eq? reply 001)
+		 (hash-table-set! conn 'registered #t)]))
+
+
+;; Handle some commands necessary for basic funcitonality
+(define (irc:process-command-internally conn command params #!optional sender)
+  (cond [(string=? command "PING")
+		 (irc:write-cmd conn "PONG" (last params))]))
+
+
 ;; Construct a string to write to IRC for the given command and parameters.
-(define (irc:cmd command . parameters)
+(define (irc:cmd->string command . parameters)
   (let ([parameters
 		 (append (reverse (cdr (reverse parameters)))
 				 `(,(string-append ":" (last parameters))))])
@@ -54,15 +111,30 @@
 	  parameters))))
 
 
-;; Join the given channel. Not much to say, really.
-(define (irc:join conn channel #!optional key)
-  (let* ([params-sans-key (list conn "JOIN" channel)]
-		 [params (if key (append params-sans-key `(,key))
-					 params-sans-key)])
-	(apply irc:write-cmd params)))
+;; Convert a string to a `msg` alist, with keys 'command', 'reply', 'params',
+;; and 'sender'.
+(define (irc:line->alist str)
+  (let* ([colon-split (string-split str " :")]
+		 [last-column (reduce string-append #f (cdr colon-split))] ;; for additional colons post-colon
+		 [other-columns (string-split (car colon-split) " ")]
+		 [sender (if (eq? #\:
+						 (car (string->list (car other-columns))))
+					 (string-drop (car other-columns) 1)
+					 #f)]
+		 [command (if sender
+					  (cadr other-columns)
+					  (car other-columns))]
+		 [reply (string->number command)]
+		 [params (append (if sender (cddr other-columns) (cdr other-columns))
+						 (list last-column))])
+	`((command ,(if (not reply) command #f))
+	  (reply ,reply)
+	  ,(append '(params) params)
+	  (sender ,sender))))
 
-
-;; Write a line to the IRC server connection.
-(define (irc:write-line text connection)
-  (print text)
-  (write-line text (cadr connection)))
+;; Just car's the value of alist-ref (if it exists)
+(define (alist-car-ref key alist)
+  (let ([value (alist-ref key alist)])
+	(if value
+		(car value)
+		#f)))