#!/bin/bash
#
# .---.                  .              .
# |                      |              |
# |--- .--. .-.  .-.  .-.|  .-. .--.--. |.-.  .-. .--.  .-.
# |    |   (.-' (.-' (   | (   )|  |  | |   )(   )|  | (.-'
# '    '     --'  --'  -' -  -' '  '   -' -'   -' '   -  --'
#
#                    Freedom in the Cloud
#
# Emacs application
#
# License
# =======
#
# Copyright (C) 2014-2016 Bob Mottram <bob@freedombone.net>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

VARIANTS='full'

IN_DEFAULT_INSTALL=1

emacs_variables=(USB_MOUNT
                 MY_USERNAME)

function reconfigure_emacs {
    echo -n ''
}

function upgrade_emacs {
    echo -n ''
}

function backup_local_emacs {
    for d in /home/*/ ; do
        USERNAME=$(echo "$d" | awk -F '/' '{print $3}')
        if [[ $(is_valid_user "$USERNAME") == "1" ]]; then
            if [ -d /home/$USERNAME/.emacs.d ]; then
                echo $"Backing up Emacs config for $USERNAME"
                if [ -f /home/$USERNAME/.emacs ]; then
                    cp /home/$USERNAME/.emacs /home/$USERNAME/.emacs.d/dotemacs
                fi
                function_check backup_directory_to_usb
                backup_directory_to_usb /home/$USERNAME/.emacs.d emacs/$USERNAME
            fi
        fi
    done
}

function restore_local_emacs {
    temp_restore_dir=/root/tempemacs
    if [ -d $USB_MOUNT/backup/emacs ]; then
        for d in $USB_MOUNT/backup/emacs/*/ ; do
            USERNAME=$(echo "$d" | awk -F '/' '{print $6}')
            if [[ $(is_valid_user "$USERNAME") == "1" ]]; then
                if [ ! -d /home/$USERNAME ]; then
                    ${PROJECT_NAME}-adduser $USERNAME
                fi
                echo $"Restoring Emacs config for $USERNAME"
                function_check restore_directory_from_usb
                restore_directory_from_usb $temp_restore_dir emacs/$USERNAME
                cp -r $temp_restore_dir/home/$USERNAME/.emacs.d /home/$USERNAME/
                if [ ! "$?" = "0" ]; then
                    rm -rf $temp_restore_dir
                    function_check set_user_permissions
                    set_user_permissions
                    function_check backup_unmount_drive
                    backup_unmount_drive
                    exit 664
                fi
                cp -f $temp_restore_dir/home/$USERNAME/.emacs.d/dotemacs /home/$USERNAME/.emacs
                rm -rf $temp_restore_dir
            fi
        done
    fi
}

function backup_remote_emacs {
    for d in /home/*/ ; do
        USERNAME=$(echo "$d" | awk -F '/' '{print $3}')
        if [[ $(is_valid_user "$USERNAME") == "1" ]]; then
            if [ -d /home/$USERNAME/.emacs.d ]; then
                echo $"Backing up Emacs config for $USERNAME"
                if [ -f /home/$USERNAME/.emacs ]; then
                    cp /home/$USERNAME/.emacs /home/$USERNAME/.emacs.d/dotemacs
                fi
                function_check backup_directory_to_friend
                backup_directory_to_friend /home/$USERNAME/.emacs.d emacs/$USERNAME
            fi
        fi
    done
}

function restore_remote_emacs {
    temp_restore_dir=/root/tempemacs
    if [ -d $USB_MOUNT/backup/emacs ]; then
        for d in $USB_MOUNT/backup/emacs/*/ ; do
            USERNAME=$(echo "$d" | awk -F '/' '{print $6}')
            if [[ $(is_valid_user "$USERNAME") == "1" ]]; then
                if [ ! -d /home/$USERNAME ]; then
                    ${PROJECT_NAME}-adduser $USERNAME
                fi
                echo $"Restoring Emacs config for $USERNAME"
                function_check restore_directory_from_friend
                restore_directory_from_friend $temp_restore_dir emacs/$USERNAME
                cp -r $temp_restore_dir/home/$USERNAME/.emacs.d /home/$USERNAME/
                if [ ! "$?" = "0" ]; then
                    rm -rf $temp_restore_dir
                    function_check set_user_permissions
                    set_user_permissions
                    function_check backup_unmount_drive
                    backup_unmount_drive
                    exit 664
                fi
                cp -f $temp_restore_dir/home/$USERNAME/.emacs.d/dotemacs /home/$USERNAME/.emacs
                rm -rf $temp_restore_dir
            fi
        done
    fi
}

function remove_emacs {
    apt-get -yq remove --purge emacs24
    update-alternatives --set editor /usr/bin/nano
    sed -i '/install_emacs/d' $COMPLETION_FILE

    # remove emacs as the mutt email editor
    if [ -f /etc/Muttrc ]; then
        if grep -q "set editor=" /etc/Muttrc; then
            sed -i '/set editor=/d' /etc/Muttrc
        fi
        for d in /home/*/ ; do
            USERNAME=$(echo "$d" | awk -F '/' '{print $3}')
            if [[ $(is_valid_user "$USERNAME") == "1" ]]; then
                if [ -f /home/$USERNAME/.muttrc ]; then
                    if grep -q "set editor=" /home/$USERNAME/.muttrc; then
                        sed -i '/set editor=/d' /home/$USERNAME/.muttrc
                    fi
                fi
            fi
        done
    fi
}

function install_emacs {
    apt-get -yq install emacs24
    update-alternatives --set editor /usr/bin/emacs24

    # A minimal emacs configuration
    #echo -n "(add-to-list 'load-path " > /home/$MY_USERNAME/.emacs
    #echo '"~/.emacs.d/")' >> /home/$MY_USERNAME/.emacs
    #echo '' >> /home/$MY_USERNAME/.emacs
    echo $';; ===== Remove trailing whitepace ======================================' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo ";;(add-hook 'before-save-hook 'delete-trailing-whitespace)" >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo ';; Goto a line number with CTRL-l' >> /home/$MY_USERNAME/.emacs
    echo -n '(global-set-key "\C-l" ' >> /home/$MY_USERNAME/.emacs
    echo "'goto-line)" >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo $';; ===== Show line numbers ==============================================' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo "(add-hook 'find-file-hook (lambda () (linum-mode 1)))" >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo $';; ===== Enable line wrapping in org-mode ===============================' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo " (add-hook 'org-mode-hook" >> /home/$MY_USERNAME/.emacs
    echo "           '(lambda ()" >> /home/$MY_USERNAME/.emacs
    echo "              (visual-line-mode 1)))" >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo $';; ===== Enable shift select in org mode ================================' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo '(setq org-support-shift-select t)' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo $';; ===== Set standard indent to 4 rather that 4 =========================' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo '(setq standard-indent 4)' >> /home/$MY_USERNAME/.emacs
    echo '(setq-default tab-width 4)' >> /home/$MY_USERNAME/.emacs
    echo '(setq c-basic-offset 4)' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo $';; ===== Support Wheel Mouse Scrolling ==================================' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo '(mouse-wheel-mode t)' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo $';; ===== Place Backup Files in Specific Directory =======================' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo '(setq make-backup-files t)' >> /home/$MY_USERNAME/.emacs
    echo '(setq version-control t)' >> /home/$MY_USERNAME/.emacs
    echo '(setq backup-directory-alist (quote ((".*" . "~/.emacs_backups/"))))' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo $';; ===== Make Text mode the default mode for new buffers ================' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo "(setq default-major-mode 'text-mode)" >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo $';; ===== Line length ====================================================' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo '(setq-default fill-column 72)' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo $';; ===== Enable Line and Column Numbering ===============================' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo '(line-number-mode 1)' >> /home/$MY_USERNAME/.emacs
    echo '(column-number-mode 1)' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo $';; ===== Turn on Auto Fill mode automatically in all modes ==============' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo ';; Auto-fill-mode the the automatic wrapping of lines and insertion of' >> /home/$MY_USERNAME/.emacs
    echo ';; newlines when the cursor goes over the column limit.' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo ';; This should actually turn on auto-fill-mode by default in all major' >> /home/$MY_USERNAME/.emacs
    echo ';; modes. The other way to do this is to turn on the fill for specific modes' >> /home/$MY_USERNAME/.emacs
    echo ';; via hooks.' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo '(setq auto-fill-mode 1)' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo $';; ===== Enable GPG encryption =========================================' >> /home/$MY_USERNAME/.emacs
    echo '' >> /home/$MY_USERNAME/.emacs
    echo "(require 'epa)" >> /home/$MY_USERNAME/.emacs
    echo '(epa-file-enable)' >> /home/$MY_USERNAME/.emacs
    cp /home/$MY_USERNAME/.emacs /root/.emacs
    chown $MY_USERNAME:$MY_USERNAME /home/$MY_USERNAME/.emacs

    # add a mutt entry to use emacs to compose emails
    if [ -f /etc/Muttrc ]; then
        if ! grep -q "set editor=" /etc/Muttrc; then
            echo 'set editor="emacs -q --load ~/.emacs-mutt"' >> /etc/Muttrc
        else
            sed -i 's|set editor=.*|set editor="emacs -q --load ~/.emacs-mutt"|g' /etc/Muttrc
        fi
        for d in /home/*/ ; do
            USERNAME=$(echo "$d" | awk -F '/' '{print $3}')
            if [[ $(is_valid_user "$USERNAME") == "1" ]]; then
                if [ -f /home/$USERNAME/.muttrc ]; then
                    if ! grep -q "set editor=" /home/$USERNAME/.muttrc; then
                        echo 'set editor="emacs -q --load ~/.emacs-mutt"' >> /home/$USERNAME/.muttrc
                    else
                        sed -i 's|set editor=.*|set editor="emacs -q --load ~/.emacs-mutt"|g' /home/$USERNAME/.muttrc
                    fi
                fi

                # create an Emacs configuration specifically for use with Mutt, which
                # has word wrap and spell checking on by default
                if [ ! -f /home/$USERNAME/.emacs-mutt ]; then
                    echo "(add-hook 'before-save-hook 'delete-trailing-whitespace)" > /home/$USERNAME/.emacs-mutt
                    echo '(setq org-support-shift-select t)' >> /home/$USERNAME/.emacs-mutt
                    echo '(setq standard-indent 4)' >> /home/$USERNAME/.emacs-mutt
                    echo '(setq-default tab-width 4)' >> /home/$USERNAME/.emacs-mutt
                    echo '(setq c-basic-offset 4)' >> /home/$USERNAME/.emacs-mutt
                    echo '(mouse-wheel-mode t)' >> /home/$USERNAME/.emacs-mutt
                    echo '(setq make-backup-files t)' >> /home/$USERNAME/.emacs-mutt
                    echo '(setq version-control t)' >> /home/$USERNAME/.emacs-mutt
                    echo '(setq backup-directory-alist (quote ((".*" . "~/.emacs_backups/"))))' >> /home/$USERNAME/.emacs-mutt
                    echo "(setq default-major-mode 'text-mode)" >> /home/$USERNAME/.emacs-mutt
                    echo "(dolist (hook '(text-mode-hook))" >> /home/$USERNAME/.emacs-mutt
                    echo '    (add-hook hook (lambda () (flyspell-mode 1))))' >> /home/$USERNAME/.emacs-mutt
                    echo '(setq-default fill-column 72)' >> /home/$USERNAME/.emacs-mutt
                    echo '(setq auto-fill-mode 0)' >> /home/$USERNAME/.emacs-mutt
                    echo "(add-hook 'text-mode-hook 'turn-on-auto-fill)" >> /home/$USERNAME/.emacs-mutt
                    echo "(setq-default auto-fill-function 'do-auto-fill)" >> /home/$USERNAME/.emacs-mutt
                    chown $USERNAME:$USERNAME /home/$USERNAME/.emacs-mutt

                    # add the emacs mutt configuration to the user profile skeleton
                    if [ ! -f /etc/skel/.emacs-mutt ]; then
                        cp /home/$USERNAME/.emacs-mutt /etc/skel/.emacs-mutt
                        chown root:root /etc/skel/.emacs-mutt
                    fi
                fi

            fi
        done
    fi

    APP_INSTALLED=1
}

function install_interactive_emacs {
    install_emacs
}

# NOTE: deliberately no exit 0