#!/bin/sh
:; set -x; exec "${EMACS:-emacs}" --debug-init --load "$0" "$@"; exit
;;
;; Try the notmuch emacs client located in ../emacs/ directory
;;
;; Run this without arguments; emacs window opens with some usage information
;;
;; Authors: Tomi Ollila <tomi.ollila@iki.fi>
;;
;; https://www.emacswiki.org/emacs/EmacsScripts was a useful starting point...
;;
;; Licence: GPLv3+
;;

(message "Starting '%s'" load-file-name)

(set-buffer "*scratch*")

(setq initial-buffer-choice nil
      inhibit-startup-screen t)

(when (featurep 'notmuch)
  (insert "
Notmuch has been loaded to this emacs (during processing of the init file)
which means it is (most probably) loaded from different source than expected.

Please run \"" (file-name-nondirectory load-file-name)
"\" with '-q' (or '-Q') as an argument, to disable
processing of the init file -- you can load it after emacs has started\n
exit emacs (y or n)? ")
  (if (y-or-n-p "exit emacs")
      (kill-emacs)
    (error "Stopped reading %s" load-file-name)))

(let ((pdir (file-name-directory
	     (directory-file-name (file-name-directory load-file-name)))))
  (unless (file-exists-p (concat pdir "emacs/notmuch-lib.el"))
    (insert "Cannot find notmuch-emacs source directory
while looking at: " pdir "emacs\n\nexit emacs (y or n)? ")
    (if (y-or-n-p "exit emacs")
	(kill-emacs)
      (error "Stopped reading %s" load-file-name)))
  (setq try-notmuch-source-directory (directory-file-name pdir)
	try-notmuch-emacs-directory (concat pdir "emacs/")
	load-path (cons try-notmuch-emacs-directory load-path)))

;; they say advice doesn't work for primitives (functions from c source)
;; well, these 'before' advice works for emacs 23.1 - 24.5 (at least)
;; ...and for our purposes 24.3 is enough (there is no load-prefer-newer there)
;; note also that the old, "obsolete" defadvice mechanism was used, but that
;; is the only one available for emacs 23 and 24 up to 24.3.

(if (boundp 'load-prefer-newer)
    (defadvice require (before before-require activate)
      (unless (featurep feature)
	(message "require: %s" feature)))
  ;; else: special require "short-circuit"; after load feature is provided...
  ;; ... in notmuch sources we always use require and there are no loops
  (defadvice require (before before-require activate)
    (unless (featurep feature)
      (message "require: %s" feature)
      (let ((name (symbol-name feature)))
	(if (and (string-match "^notmuch" name)
		 (file-newer-than-file-p
		  (concat try-notmuch-emacs-directory name ".el")
		  (concat try-notmuch-emacs-directory name ".elc")))
	    (load (concat try-notmuch-emacs-directory name ".el") nil nil t t)
	  )))))

(insert "Found notmuch emacs client in " try-notmuch-emacs-directory "\n")

(let ((notmuch-path (executable-find "notmuch")))
  (insert "Notmuch CLI executable "
	  (if notmuch-path (concat "is " notmuch-path) "not found!") "\n"))

(condition-case err
;; "opportunistic" load-prefer-newer -- will be effective since emacs 24.4
    (let ((load-prefer-newer t)
	  (force-load-messages t))
      (require 'notmuch))
  ;; specifying `debug' here lets the debugger run
  ;; if `debug-on-error' is non-nil.
  ((debug error)
   (let ((error-message-string (error-message-string err)))
     (insert "\nLoading notmuch failed: " error-message-string "\n")
     (message "Loading notmuch failed: %s" error-message-string)
     (insert "See *Messages* buffer for more information.\n")
     (if init-file-user
	 (message "Hint: %s -q (or -Q) may help" load-file-name))
     (pop-to-buffer "*Messages*")
     (error "Stopped reading %s" load-file-name))))

(insert "
Go to the end of the following lines and type C-x C-e to evaluate
(or C-j which is shorter but inserts evaluation results into buffer)

To \"disable\" mail sending, evaluate
* (setq message-send-mail-function (lambda () t))
")

(if (file-exists-p (concat try-notmuch-source-directory "/notmuch"))
    (insert "
To use accompanied notmuch binary from the same source, evaluate
* (setq exec-path (cons \"" try-notmuch-source-directory  "\" exec-path))
Note: Evaluating the above may be followed by unintended database
upgrade and getting back to old version may require dump & restore.
"))

(if init-file-user ;; nil, if '-q' or '-Q' is given, but no '-u' 'USER'
    (insert "
Your init file was processed during emacs startup. If you want to test
notmuch emacs mail client without your emacs init file interfering, Run\n\""
(file-name-nondirectory load-file-name) "\" with '-q' (or '-Q') as an argument.
")
  (let ((emacs-init-file-name) (notmuch-init-file-name))
    ;; determining init file name in startup.el/command-line is too complicated
    ;; to be duplicated here; these 3 file names covers most of the users
    (mapc (lambda (fn) (if (file-exists-p fn) (setq emacs-init-file-name fn)))
	  '("~/.emacs.d/init.el" "~/.emacs" "~/.emacs.el"))
    (setq notmuch-init-file-name "~/.emacs.d/notmuch-config.el")
    (unless (file-exists-p notmuch-init-file-name)
	(setq notmuch-init-file-name nil))
    (if (and emacs-init-file-name notmuch-init-file-name)
	(insert "
If you want to load your initialization files now, evaluate\n* (progn")
      (if (or emacs-init-file-name notmuch-init-file-name)
	  (insert "
If you want to load your initialization file now, evaluate\n*")))
    (if emacs-init-file-name
	(insert " (load \"" emacs-init-file-name "\")"))
    (if notmuch-init-file-name
	(insert " (load \"" notmuch-init-file-name "\")"))
    (if (and emacs-init-file-name notmuch-init-file-name)
	(insert ")"))
    (if (or emacs-init-file-name notmuch-init-file-name)
	(insert "\n")))
  (if (>= emacs-major-version 24)
      (insert "
If you want to use packages (e.g. company from elpa) evaluate
* (progn (require 'package) (package-initialize))
")))

(insert "
To start notmuch (hello) screen, evaluate
* (notmuch-hello)")

(add-hook 'emacs-startup-hook
	  (lambda ()
	    (with-current-buffer "*scratch*"
	      (lisp-interaction-mode)
	      (goto-char (point-min))
	      (forward-line 2)
	      (set-buffer-modified-p nil))))

;; Local Variables:
;; mode: emacs-lisp
;; End: