;;; el-get --- Manage the external elisp bits and pieces you depend upon
;;
;; Copyright (C) 2010-2011 Dimitri Fontaine
;;
;; Author: Dimitri Fontaine <dim@tapoueh.org>
;; URL: http://www.emacswiki.org/emacs/el-get
;; GIT: https://github.com/dimitri/el-get
;; Licence: WTFPL, grab your copy here: http://sam.zoy.org/wtfpl/
;;
;; This file is NOT part of GNU Emacs.
;;
;; Install
;;     Please see the README.asciidoc file from the same distribution

(require 'el-get-core)
(require 'package nil t)

(defcustom el-get-elpa-install-hook nil
  "Hook run after ELPA package install."
  :group 'el-get
  :type 'hook)

(defcustom el-get-elpa-remove-hook nil
  "Hook run after ELPA package remove."
  :group 'el-get
  :type 'hook)

(defun el-get-elpa-package-directory (package)
  "Return the directory where ELPA stores PACKAGE, or nil if
PACKAGE isn't currently installed by ELPA."
  (let* ((pname (format "%s" package))  ; easy way to cope with symbols etc.

	 (l
	  ;; we use try-completion to find the realname of the directory
	  ;; ELPA used, and this wants an alist, we trick ls -i -1 into
	  ;; that.
	  (mapcar 'split-string
		  (split-string
		   (shell-command-to-string
		    (concat
		     "ls -i1 "
		     (expand-file-name
		      (file-name-as-directory package-user-dir)))))))

	 (realname (try-completion pname l)))

    (if realname (concat (file-name-as-directory package-user-dir) realname)
      realname)))

(defun el-get-elpa-package-repo (package)
  "Get the ELPA repository cons cell for PACKAGE.

The cons cell has the form (NAME . URL). See `package-archives'.
If the package source only specifies a URL, the URL will be used
for NAME as well.

If PACKAGE's `:type' is not \"elpa\", or no repo is specified in
the recipe, then return nil."
  (let* ((source (el-get-package-def package))
         (type   (el-get-package-type source))
         (elpa-repo (plist-get source :repo)))
    (when (and (eq type 'elpa) elpa-repo)
      (cond ((stringp elpa-repo)
             (cons elpa-repo elpa-repo))
            ((consp elpa-repo)
             (if (and (stringp (car elpa-repo))
                      (stringp (cdr elpa-repo)))
                 elpa-repo
               (error "Invalid elpa repo spec: %s" elpa-repo)))
            (t
             (error "Invalid elpa repo spec: %s" elpa-repo))))))

(defun el-get-elpa-symlink-package (package)
  "ln -s ../elpa/<package> ~/.emacs.d/el-get/<package>"
  (let ((elpa-dir (file-relative-name
		   (el-get-elpa-package-directory package) el-get-dir)))
    (unless (el-get-package-exists-p package)
      ;; better style would be to check for (fboundp 'make-symbolic-link) but
      ;; that would be true on Vista, where by default only administrator is
      ;; granted to use the feature --- so hardcode those systems out
      (if (memq system-type '(ms-dos windows-nt))
	  ;; the symlink is a docs/debug feature, mkdir is ok enough
	  (make-directory (el-get-package-directory package))
	(message "%s"
		 (shell-command
		  (concat "cd " el-get-dir
			  " && ln -s \"" elpa-dir "\" \"" package "\"")))))))

(defun el-get-elpa-install (package url post-install-fun)
  "Ask elpa to install given PACKAGE."
  (let* ((elpa-dir (el-get-elpa-package-directory package))
         (elpa-repo (el-get-elpa-package-repo package))
         ;; Set `package-archive-base' to elpa-repo for old package.el
         (package-archive-base (or (cdr-safe elpa-repo)
                                   (bound-and-true-p package-archive-base)))
         ;; Prepend elpa-repo to `package-archives' for new package.el
         (package-archives (append (when elpa-repo (list elpa-repo))
                                   (when (boundp 'package-archives) package-archives))))
    (unless (and elpa-dir (file-directory-p elpa-dir))
      ;; Make sure we have got *some* kind of record of the package archive.
      ;; TODO: should we refresh and retry once if package-install fails?
      (let ((p (if (fboundp 'package-read-all-archive-contents)
		   (package-read-all-archive-contents) ; version from emacs24
		 (package-read-archive-contents)))     ; old version
            ;; package-install generates autoloads, byte compiles
            emacs-lisp-mode-hook fundamental-mode-hook prog-mode-hook)
	(unless p
	  (package-refresh-contents)))
      (package-install (intern package)))
    ;; we symlink even when the package already is installed because it's
    ;; not an error to have installed ELPA packages before using el-get, and
    ;; that will register them
    (el-get-elpa-symlink-package package))
  (funcall post-install-fun package))

(defun el-get-elpa-update (package url post-update-fun)
  "Ask elpa to update given PACKAGE."
  (el-get-elpa-remove package url nil)
  (package-refresh-contents)
  (package-install (intern package))
  (funcall post-update-fun package))

(defun el-get-elpa-remove (package url post-remove-fun)
  "Remove the right directory where ELPA did install the package."
  (el-get-rmdir package url post-remove-fun))

(defun el-get-elpa-post-remove (package)
  "Do remove the ELPA bits for package, now"
  (let ((p-elpa-dir (el-get-elpa-package-directory package)))
    (if p-elpa-dir
	(dired-delete-file p-elpa-dir 'always)
      (message "el-get: could not find ELPA dir for %s." package))))

(add-hook 'el-get-elpa-remove-hook 'el-get-elpa-post-remove)

(el-get-register-method
 :elpa #'el-get-elpa-install #'el-get-elpa-update #'el-get-elpa-remove
 #'el-get-elpa-install-hook #'el-get-elpa-remove-hook)

(provide 'el-get-elpa)