;; emchat-utils.el --- misc utils for EMchat   -*- Emacs-Lisp -*-

;; Copyright (C) 2007 - 2011 Steve Youngs

;; Author:     Steve Youngs <steve@emchat.org>
;; Maintainer: Steve Youngs <steve@emchat.org>
;; Created:    <2007-09-01>
;; Homepage:   http://www.emchat.org/
;; Keywords:   utils ICQ emchat

;; This file is part of EMchat.

;; Redistribution and use in source and binary forms, with or without
;; modification, are permitted provided that the following conditions
;; are met:
;;
;; 1. Redistributions of source code must retain the above copyright
;;    notice, this list of conditions and the following disclaimer.
;;
;; 2. Redistributions in binary form must reproduce the above copyright
;;    notice, this list of conditions and the following disclaimer in the
;;    documentation and/or other materials provided with the distribution.
;;
;; 3. Neither the name of the author nor the names of any contributors
;;    may be used to endorse or promote products derived from this
;;    software without specific prior written permission.
;;
;; THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
;; IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
;; WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
;; DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
;; FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
;; CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
;; SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
;; BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
;; WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
;; OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
;; IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

;;; Commentary:
;;
;;    This is where any general-purpose utils for EMchat go

;;; Code:
(eval-when-compile
  (defvar emchat-all-aliases))

(defcustom emchat-glyph-dir
  (file-name-as-directory (or (locate-data-directory "emchat") ""))
  "Directory where icons and logos live."
  :type 'directory
  :group 'emchat-interface)

;;; Internal variables

(defmacro emchat-do-in-xemacs (&rest body)
  "Execute BODY if in XEmacs."
  (when (featurep '(and xemacs (not sxemacs)))
    `(progn ,@body)))

(put 'emchat-do-in-xemacs 'lisp-indent-hook 'defun)

(defmacro emchat-do-in-sxemacs (&rest body)
  "Execute BODY if in SXEmacs."
  (when (featurep 'sxemacs)
    `(progn ,@body)))

(put 'emchat-do-in-sxemacs 'lisp-indent-hook 'defun)

(defun emchat-completing-read
  (prompt table &optional predicate require-match initial-contents history)
  "Args: PROMPT, TABLE, PREDICATE, REQUIRE-MATCH, INITIAL-CONTENTS, HISTORY.
Same as `completing-read' but accepts strings as well as obarray."
  (completing-read
   prompt
   (if (vectorp table)
       table (mapcar 'list table))
   predicate require-match initial-contents history))

(defun emchat-numeric-uin (uin)
  "Return UIN as number.
UIN can be either a string or number."
  (cond ((numberp uin) uin)
	((stringp uin) (string-to-number uin))
	(t (error "Invalid UIN type" uin))))

(defun emchat-stringular-uin (uin)
  "Return UIN as a string.
UIN can be either a string or a number."
  (cond ((numberp uin) (number-to-string uin))
	((stringp uin) uin)
	(t (error "Invalid UIN type" uin))))

(defun emchat-valid-uin-p (uin)
  "Return non-nil if UIN is a valid uin."
  (not (zerop (emchat-numeric-uin uin))))

(defun emchat-completing-aliases (prompt &optional single)
  "Completing-read aliases/uin.
PROMPT is the prompt for reading.
SINGLE means read only one alias/uin.

Must at least complete one alias, use RET (empty string) to finish
entering. It first completing-reads from the union of `emchat-active-aliases'
and `emchat-connected-aliases'. If you hit RET and the input string is not in
the union it the completing-reads from `emchat-all-aliases'.

Tips: You can also enter an uin in place of an alias."
  (let ((aliases
	 ;; a must for first one
	 (cons (emchat-completing-alias prompt 'required)
	       (unless single
		 (loop collect (emchat-completing-alias prompt nil)
		       into aliases
		       ;; empty string means abort
		       until (string= (car (last aliases)) "")
		       finally return (nbutlast aliases))))))
    (delete-duplicates aliases :test 'string=)))

(defun emchat-completing-alias (prompt required)
  "Completing only one alias/uin.
PROMPT is the prompt for reading.
REQUIRED means cannot abort.
Used by `emchat-completing-aliases'.
No abortion when `** ' is in prompt.
Abort by RET (empty string) when `++ ' is in prompt."
  (let ((all emchat-all-aliases)
	(alias
	  (emchat-completing-read
	   prompt
	   emchat-all-aliases
	   nil nil nil 'emchat-alias-history)))
    (unless (or
	     ;; valid alias
	     (member alias all)
	     ;; valid uin
	     (emchat-valid-uin-p alias)
	     ;; abort
	     (and (string= alias "")
		  (not required)))
      (loop do
	(setq alias
	      (emchat-completing-read
	       (concat (if required "** " "++ ") prompt)
	       all nil t alias 'emchat-alias-history))
	while (and (string= alias "") required)))
    alias))

(defun emchat-switch-buffer (buffer)
  (when buffer
    (select-window (get-buffer-window buffer))))



(provide 'emchat-utils)
;;; emchat-utils.el ends here