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diff --git a/package.lisp b/package.lisp
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+;;;; package.lisp
+
+(defpackage #:posterbot
+  (:use #:cl #:granolin))
diff --git a/posterbot.asd b/posterbot.asd
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+++ b/posterbot.asd
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+;;;; posterbot.asd
+
+(asdf:defsystem #:posterbot
+  :description "A Matrix bot to post media links."
+  :author "Colin Okay <cbeok@protonmail.com>"
+  :license  "AGPL"
+  :version "0.0.1"
+  :serial t
+  :depends-on (#:granolin #:cl-ppcre #:alexandria #:cl-fad)
+  :components ((:file "package")
+               (:file "posterbot")))
diff --git a/posterbot.lisp b/posterbot.lisp
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+++ b/posterbot.lisp
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+;;;; posterbot.lisp
+
+(in-package #:posterbot)
+
+(defclass posterbot (client auto-joiner) ())
+
+(defvar *posterbot* nil "dynamic variable holding the bot so I dont have to pass it around")
+
+(defparameter +image-link-regex+
+  (ppcre:create-scanner "http.+\.(png|gif|jpeg|bmp|jpg)"
+                        :case-insensitive-mode t))
+
+(defun download-link (link)
+  (cl-fad:with-output-to-temporary-file (out :element-type '(unsigned-byte 8))
+    (let ((buffer (make-array 4096 :element-type '(unsigned-byte 8)))
+          (file-stream  (drakma:http-request link :want-stream t)))
+      (loop :for bytes = (read-sequence buffer file-stream)
+         :while (plusp bytes) :do (write-sequence buffer out)))))
+
+
+(defun filename-from-link (link)
+  (first (last (ppcre:split "/" link))))
+
+(defun make-mime-type (filename)
+  (format nil "image/~a" (pathname-type filename)))
+
+(defun handle-link-candiate (word)
+  (let ((link (ppcre:scan-to-strings +image-link-regex+ word)))
+    (when link
+      (let* ((file-path (download-link link))
+             (file-name (filename-from-link link))
+             (mxc-uri 
+              (upload *posterbot*
+                      file-name
+                      (alexandria:read-file-into-byte-vector file-path)
+                      :content-type (make-mime-type word))))
+        (send-image-message *posterbot* *room-id* file-name mxc-uri
+                            :info (list :|mimetype| (make-mime-type word)))))))
+
+;; look for links to images, one word at a time, downloading and
+;; posting any images found to the room at the current *ROOM-ID*
+(defmethod handle-event :after ((*posterbot* posterbot) (event text-message-event))
+  (mapc #'handle-link-candiate (ppcre:split " " (msg-body event))))