#!/usr/bin/env bash
# HEADER
#=======================================================================
#
#  email -- Shell script to sync my emails with isync and read 
#           them with mutt.
#
#  SYNOPSIS
#    email <account>
#
#  DESCRIPTION
#    Shell script to get my email with `isync` (tool to sync mail 
#    from IMAP servers) and read them width `mutt`.
#
#  EXAMPLES
#    $ email account
#    $ email -n account
#
#  POSITIONAL ARGUMENT
#    <account>              mail account
#
#   known as "account" in your isync configuration file
#       ~/.mbsyncrc
#   that is in
#      grep -e "^IMAPAccount" ~/.mbsyncrc | cut -d" " -f2
#   and define with a mutt configuration file in
#      ~/Mail/.config/${MailAccount}.rc
#                           
#
#  OPTIONAL ARGUMENTS
#    -h, --help             show this help message and exit
#    -l, --list             list mail accounts
#    -n, --new              just check for new emails
#    -N, --allnew           just check for new emails for all accounts
#    -o, --offline          offline mode - do not call offlineimap
#    -r, -R, --readonly     read only mode - do not write anything
#
#  DEPENDENCIES
#    - isync
#    - mutt
# 
#  INSTALLATION
#     - link file in $PATH (~/bin/)
#     - add completion script in "~/.bashrc":
#         _email_completions(){
#             local cur prev opts
#             COMPREPLY=()
#             cur="${COMP_WORDS[COMP_CWORD]}"
#             prev="${COMP_WORDS[COMP_CWORD-1]}"
#             opts=$(grep -e "^IMAPAccount" ~/.mbsyncrc \
#                   | cut -d" " -f2 | tr -d ']' | xargs )" local -o -n"
#             if [[ ${cur} == * ]] ; then
#                 COMPREPLY=( $(compgen -W "${opts}" -- ${cur}) )
#                 return 0
#             fi
#         }
#         complete -F _email_completions email
#
#  Copyright (C) 2020 Nicolas Mesnier <nmesnier@free.fr>
#
#  This program is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License version 3 or
#  above as published by the Free Software Foundation.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with this program. If not, see <http://www.gnu.org/licenses/>.
#
#=======================================================================
# END_OF_HEADER
#-----------------------------------------------------------------------
# *** read this header to display help and version
#-----------------------------------------------------------------------
BOH=$(head -200 ${0} | grep -n "^# HEADER" | cut -f1 -d:)
EOH=$(head -200 ${0} | grep -n "^# END_OF_HEADER" | cut -f1 -d:)
function Help(){
  head -$(($EOH-1)) ${0} | tail -$(($EOH-$BOH-1)) \
    | grep -e "^#$" -e "^# " | sed -e "s/^#=*//g"
}
#-----------------------------------------------------------------------
# *** parameters ***
#-----------------------------------------------------------------------
account_list=$(grep -e "^IMAPAccount" ~/.mbsyncrc | cut -d" " -f2 | xargs )
accounts="@("$(echo ${account_list}| tr ' ' '|')")"
#-----------------------------------------------------------------------
# *** get options ***
#-----------------------------------------------------------------------
MailAccount=""
muttOptions=""
OnlyNew=false
offline=false
readOnly=false
AllNew=false
shopt -s extglob
while [[ ${1} ]]; do
    case "${1}" in
        -h|--help) 
            Help
            exit 0 ;;
        -l|--list) 
            echo " *** List of accounts:"
            echo " "${account_list}
            exit 0 ;;
        -n|--new)
            OnlyNew=true
            ;;
        -N|--allnew)
            AllNew=true
            ;;
        -o|--offline)
            offline=true
            ;;
        -r|-R|--readonly)
            readOnly=true
            ;;
        *)
            if [ -z ${MailAccount} ];then
                case "${1}" in
                    ${accounts}|local)
                        MailAccount=${1}
                        ;;
                    *)
                    echo "Uknown mail account \"${1}\"." >&2
                    echo "Must be part of: "${account_list} >&2
                    exit 1
                    ;;
                esac
            else
                echo "Mail account \"${MailAccount}\" allready given." >&2
                exit 1
            fi
            ;;
    esac
    if ! shift; then
        echo 'Missing parameter argument.' >&2
        exit 1
    fi
done
#-----------------------------------------------------------------------
# *** run
#-----------------------------------------------------------------------
if [ "${AllNew}" = true ];then
    for MailAccount in ${account_list};do
        echo " *** Processing account "${MailAccount}
        mbsync -q ${MailAccount} \
        && mutt -F ~/Mail/.config/${MailAccount}.rc -Z
    done
else
    case ${MailAccount} in 
        ${accounts})
            if [ "${OnlyNew}" = true ];then
                mbsync -nd -q ${MailAccount} \
                && mutt -F ~/Mail/.config/${MailAccount}.rc -Z
            elif [ "${offline}" = true ];then
                mutt -F ~/Mail/.config/${MailAccount}.rc
            elif [ "${readOnly}" = true ];then
                mutt -R -F ~/Mail/.config/${MailAccount}.rc
            else
                mbsync -q ${MailAccount} \
                && mutt -F ~/Mail/.config/${MailAccount}.rc
            fi
            ;;
        local)
            mutt -F ~/Mail/.config/${MailAccount}.rc
            ;;
    esac
fi
#====================================================================eof
# vim: set tw=72 ts=4 sw=4 nu: