#!/bin/sh

prefix="/usr/local"
maildir="${XDG_DATA_HOME:-$HOME/.local/share}/mail"
muttshare="$prefix/share/mutt-wizard"
cachedir="${XDG_CACHE_HOME:-$HOME/.cache}/mutt-wizard"
muttrc="${XDG_CONFIG_HOME:-$HOME/.config}/mutt/muttrc"
accdir="${XDG_CONFIG_HOME:-$HOME/.config}/mutt/accounts"
msmtprc="${XDG_CONFIG_HOME:-$HOME/.config}/msmtp/config"
msmtplog="${XDG_CONFIG_HOME:-$HOME/.config}/msmtp/msmtp.log"
mbsyncrc="${MBSYNCRC:-$HOME/.mbsyncrc}"
mpoprc="${XDG_CONFIG_HOME:-$HOME/.config}/mpop/config"
alias mbsync='mbsync -c "$mbsyncrc"'

for x in "/etc/ssl/certs/ca-certificates.crt" "/etc/pki/tls/certs/ca-bundle.crt" "/etc/ssl/ca-bundle.pem" "/etc/pki/tls/cacert.pem" "/etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem" "/etc/ssl/cert.pem" "/usr/local/share/ca-certificates/"; do
	[ -f "$x" ] && sslcert="$x" && break
done || { echo "CA Certificate not found. Please install one or link it to /etc/ssl/certs/ca-certificates.crt" && exit 1 ;}

checkbasics() { command -V gpg >/dev/null 2>&1 && GPG="gpg" || GPG="gpg2"
	PASSWORD_STORE_DIR="${PASSWORD_STORE_DIR:-$HOME/.password-store}"
	[ -r "$PASSWORD_STORE_DIR/.gpg-id" ] &&
	"$GPG" --list-secret-keys "$(cat "$PASSWORD_STORE_DIR/.gpg-id")" >/dev/null 2>&1 || {
	echo "First run \`pass init <yourgpgemail>\` to set up a password archive."
	echo "(If you don't already have a GPG key pair, first run \`$GPG --full-generate-key\`.)"
       	exit 1 ;} ;}

getaccounts() { accounts="$(find -L "$accdir" -type f 2>/dev/null | grep -o "[0-9]-.*.muttrc" | sed "s/-/: /;s/\.muttrc$//" | sort -n)" ;}

list() { getaccounts && [ -n "$accounts" ] && echo "$accounts" || exit 1 ;}

prepmsmtp() { echo "account $fulladdr
host $smtp
port ${sport:-587}
from $fulladdr
user $login
passwordeval \"pass $fulladdr\"
auth ${auth:-on}
${tlsline:-tls on}
tls_trust_file	$sslcert
logfile $msmtplog
" >> "$msmtprc"
	# On Ubuntu/Debian, a link is needed since they use an older version.
	command -V apt-get >/dev/null 2>&1 && ln -s "$msmtprc" "$HOME/.msmtprc" 2>/dev/null
}

prepmbsync() { mkdir -p "${mbsyncrc%/*}"
	echo "
IMAPStore $fulladdr-remote
Host $imap
Port ${iport:-993}
User $login
PassCmd \"pass $fulladdr\"
AuthMechs LOGIN
SSLType ${imapssl:-IMAPS}
CertificateFile $sslcert

MaildirStore $fulladdr-local
Subfolders Verbatim
Path ${XDG_DATA_HOME:-$HOME/.local/share}/mail/$fulladdr/
Inbox ${XDG_DATA_HOME:-$HOME/.local/share}/mail/$fulladdr/${inbox:-INBOX}

Channel $fulladdr
Expunge Both
Master :$fulladdr-remote:
Slave :$fulladdr-local:
Patterns * !\"[Gmail]/All Mail\"
Create Both
SyncState *
MaxMessages ${maxmes:-0}
ExpireUnread no
# End profile
" >> "$mbsyncrc" ;}

prepmpop() { mkdir -p "${mpoprc%/*}"
	echo "
account $fulladdr
tls on
user $login
host $imap
delivery maildir ${XDG_DATA_HOME:-$HOME/.local/share}/mail/$fulladdr/${inbox:-INBOX}
passwordeval pass $fulladdr
" >> "$mpoprc" ;}

prepmutt() { echo "# vim: filetype=neomuttrc
# muttrc file for account $fulladdr
set realname = \"$realname\"
set from = \"$fulladdr\"
set sendmail = \"msmtp -a $fulladdr\"
alias me $realname <$fulladdr>
set folder = \"$folder\"
set header_cache = $cachedir/$fulladdr/headers
set message_cachedir = $cachedir/$fulladdr/bodies
set mbox_type = Maildir
$extra

bind index,pager gg noop
bind index,pager g noop
bind index,pager M noop
bind index,pager C noop
bind index gg first-entry
unmailboxes *
unalternates *
unset signature
$synccmd
" > "$accdir/$idnum-$fulladdr.muttrc"

	[ ! -f "$muttrc" ] && echo "# vim: filetype=neomuttrc" > "$muttrc"
	! grep -q "^source.*mutt-wizard.muttrc" "$muttrc" && echo "source $muttshare/mutt-wizard.muttrc" >> "$muttrc"
	! grep "^source.*.muttrc" "$muttrc" | grep -qv "$muttshare/mutt-wizard.muttrc" && echo "source $accdir/$idnum-$fulladdr.muttrc" >> "$muttrc"
	echo "macro index,pager i$idnum '<sync-mailbox><enter-command>source $accdir/$idnum-$fulladdr.muttrc<enter><change-folder>!<enter>;<check-stats>' \"switch to $fulladdr\"" >> "$muttrc"
}

getprofiles() { \
	mkdir -p "${muttrc%/*}" "$accdir" "$cachedir/$fulladdr/bodies" "${XDG_CONFIG_HOME:-$HOME/.config}/msmtp"
	unset msmtp_header msmtp_profile mutt_profile mbsync_profile
	case "$iport" in
		1143) imapssl=None ;;
		143) imapssl=STARTTLS ;;
	esac
	case "$type" in
		online) folder="imaps://$login@$imap:${iport:-993}"
extra="set imap_user = \"$login\"
set imap_pass = \"\`pass $fulladdr\`\"
set ssl_starttls = yes
set ssl_force_tls = yes"
			;;
		pop) synccmd="macro index o \"<shell-escape>mpop $fulladdr<enter>\" \"run mpop to get $fulladdr's mail\""
			folder="$maildir/$fulladdr"
			prepmpop ;;
		*) synccmd="macro index o \"<shell-escape>mbsync $fulladdr<enter>\" \"run mbsync to sync $fulladdr\""
			folder="$maildir/$fulladdr"
			prepmbsync ;;
	esac
	prepmsmtp
	prepmutt

	prepnotmuch # Create a notmuch config file if not present already.
}

parsedomains(){ serverinfo="$(grep "^${fulladdr#*@}" "$muttshare/domains.csv" 2>/dev/null)"

	[ -z "$serverinfo" ] && serverinfo="$(grep "$(echo "${fulladdr#*@}" | sed "s/\.[^\.]*$/\.\\\*/")" "$muttshare/domains.csv" 2>/dev/null)"

	IFS=, read -r service imapsugg iportsugg smtpsugg sportsugg <<EOF
$serverinfo
EOF
	imap="${imap:-$imapsugg}"
	smtp="${smtp:-$smtpsugg}"
	sport="${sport:-$sportsugg}"
	iport="${iport:-$iportsugg}"
}

delete() { if [ -z "${fulladdr+x}" ]; then
		echo "Select the account you would like to delete (by number):"
		list || exit 1
		read -r input
		match="^$input:"
	else
		match=" $fulladdr$"
		getaccounts
	fi

	fulladdr="$(echo "$accounts" | grep "$match" | cut -f2 -d' ')"

	[ -z "$fulladdr" ] && echo "$fulladdr is not a valid account name." && return 1

	sed -ibu "/IMAPStore $fulladdr-remote$/,/# End profile/d" "$mbsyncrc" 2>/dev/null ; rm -f "$mbsyncrc"bu
	rm -rf "${cachedir:?}/${fulladdr:?}" "$accdir/"[1-9]"-$fulladdr.muttrc"
	sed -ibu "/[0-9]-$fulladdr.muttrc/d" "$muttrc" 2>/dev/null; rm -f "$muttrc"bu
	sed -ibu "/account $fulladdr$/,/^\(\s*$\|account\)/d" "$msmtprc" 2>/dev/null; rm -f "$msmtprc"bu
	sed -ibu "/account $fulladdr$/,/^\(\s*$\|account\)/d" "$mpoprc" 2>/dev/null; rm -f "$mpoprc"bu
	pass rm -f "$fulladdr" >/dev/null 2>&1
	[ -n "${purge+x}" ] && rm -rf "${maildir:?}/${fulladdr:?}"

	for file in "$msmtprc" "$mbsyncrc" "$mpoprc"; do
		sed -ibu 'N;/^\n$/D;P;D;' "$file" 2>/dev/null; rm -f "$file"bu
	done
}

askinfo() { \
	[ -z "$fulladdr" ] && echo "Give the full email address to add:" &&
		read -r fulladdr
	while ! echo "$fulladdr" | grep -qE "^.+@.+\.[A-Za-z]+$"; do
		echo "\`$fulladdr\` is not a valid email address. Please retype the address:"
		read -r fulladdr
	done
	getaccounts; echo "$accounts" | grep -q "\s$fulladdr$" 2>/dev/null &&
		{ echo "$fulladdr has already been added" && exit 1 ;}
	{ [ -z "$imap" ] || [ -z "$smtp" ] ;} && parsedomains
	[ -z "$imap" ] && echo "Give your email server's IMAP address (excluding the port number):" &&
		read -r imap
	[ -z "$smtp" ] && echo "Give your email server's SMTP address (excluding the port number):" &&
		read -r smtp
	[ "$sport" = 465 ] && tlsline="tls_starttls off"
	[ -z "$realname" ] && realname="${fulladdr%%@*}"
	login="${login:-$fulladdr}"
	if [ -n "${password+x}" ]; then
		createpass
	else
		getpass
	fi
}

createpass() { echo "$password" > "$PASSWORD_STORE_DIR/$fulladdr"
	"$GPG" -qer "$(cat "$PASSWORD_STORE_DIR/.gpg-id")" "$PASSWORD_STORE_DIR/$fulladdr"
	rm -f "$PASSWORD_STORE_DIR/$fulladdr" ;}

getpass() { while : ; do pass rm -f "$fulladdr" >/dev/null 2>&1
		pass insert -f "$fulladdr" && break; done ;}

formatShortcut() { toappend="$toappend
macro index,pager g$1 \"<change-folder>=$3<enter>\" \"go to $2\"
macro index,pager M$1 \";<save-message>=$3<enter>\" \"move mail to $2\"
macro index,pager C$1 \";<copy-message>=$3<enter>\" \"copy mail to $2\"" ;}

setBox() { toappend="$toappend
set $1 = \"+$2\"" ;}

getboxes() { if [ -n "${force+x}" ] ; then
		mailboxes="$(printf "INBOX\\nDrafts\\nJunk\\nTrash\\nSent\\nArchive")"
	else
		info="$(curl --location-trusted -s -m 5 --user "$login:$(pass "$fulladdr")" --url "${protocol:-imaps}://$imap:${iport:-993}")"
		[ -z "$info" ] && echo "Log-on not successful." && return 1
		mailboxes="$(echo "$info" | grep -v HasChildren | sed "s/.*\" //;s/\"//g" | tr -d '
')"
	fi
	[ "$type" = "pop" ] && mailboxes="INBOX"
	getaccounts; for x in $(seq 1 9); do echo "$accounts" | grep -q "^$x:" || { export idnum="$x"; break ;}; done
	toappend="mailboxes $(echo "$mailboxes" | sed "s/^/\"=/;s/$/\"/" | paste -sd ' ' - )"
	for x in $mailboxes; do
		case "$x" in
			*[Ss][Ee][Nn][Tt]*) setBox record "$x"; formatShortcut s sent "$x" ;;
			*[Dd][Rr][Aa][Ff][Tt][Ss]*) setBox postponed "$x"; formatShortcut d drafts "$x" ;;
			*[Tt][Rr][Aa][Ss][Hh]*) formatShortcut t trash "$x"; setBox trash "$x" ;;
			*[Jj][Uu][Nn][Kk]*) formatShortcut j junk "$x" ;;
			*[Aa][Rr][Cc][Hh][Ii][Vv][Ee]*) formatShortcut a archive "$x" ;;
			*[Ss][Pp][Aa][Mm]*) formatShortcut S spam "$x" ;;
			*[Ii][Nn][Bb][Oo][Xx]) formatShortcut i inbox "$x"; setBox spoolfile "$x" inbox="$x" ;;
		esac
	done
}

finalize() { echo "$toappend" >> "$accdir/$idnum-$fulladdr.muttrc"
	[ "$type" != "online" ] && echo "$mailboxes" | xargs -I {} mkdir -p "$maildir/$fulladdr/{}/cur" "$maildir/$fulladdr/{}/tmp" "$maildir/$fulladdr/{}/new"
	echo "$fulladdr (account #$idnum) added successfully."
	command -V urlview >/dev/null 2>&1 && [ ! -f "$HOME/.urlview" ] && echo "COMMAND \$BROWSER" > "$HOME/.urlview"
	return 0 ;}

prepnotmuch() { \
	[ -z "$NOTMUCH_CONFIG" ] && NOTMUCH_CONFIG="$HOME/.notmuch-config"
	[ -f "$NOTMUCH_CONFIG" ] && return 0
	nmbasic="[database]
path=$maildir
[user]
name=$realname
primary_email=$fulladdr
[new]
tags=unread;inbox;
ignore=.mbsyncstate;.uidvalidity
[search]
exclude_tags=deleted;spam;
[maildir]
synchronize_flags=true
[crypto]
gpg_path=$GPG"
	echo "$nmbasic" > "$NOTMUCH_CONFIG" ;}

togglecron() { cron="$(mktemp)"
	crontab -l > "$cron"
	if grep -q mailsync "$cron"; then
		echo "Removing automatic mailsync..."
		sed -ibu /mailsync/d "$cron"; rm -f "$cron"bu
	else
		echo "Adding automatic mailsync every ${cronmin:-10} minutes..."
		echo "*/${cronmin-10} * * * * $prefix/bin/mailsync" >> "$cron"
	fi &&
	crontab "$cron"; rm -f "$cron" ;}

setact() { if [ -n "${action+x}" ] && [ "$action" != "$1" ]; then
		echo "Running $1 with $action..."
		echo "Incompatible options given. Only one action may be specified per run."
		return 1
	else
		action="$1"
	fi; }

mwinfo() { cat << EOF
mw: mutt-wizard, auto-configure email accounts for mutt
including downloadable mail with \`isync\`.

Main actions:
  -a your@email.com	Add an email address
  -l			List email addresses configured
  -d			Remove an already added address
  -D your@email.com	Force remove account without confirmation
  -y your@email.com	Sync mail for account by name
  -Y			Sync mail for all accounts
  -t number		Toggle automatic mailsync every <number> minutes
  -T			Toggle automatic mailsync

Options allowed with -a:
  -u	Account login name if not full address
  -n	"Real name" to be on the email account
  -i	IMAP/POP server address
  -I	IMAP/POP server port
  -s	SMTP server address
  -S	SMTP server port
  -x	Password for account (recommended to be in double quotes)
  -p	Install for a Protonmail account.
  -P	Add for a POP server instead of IMAP.
  -X	Delete an account's local email too when deleting.
  -o	Configure address, but keep mail online.
  -f	Assume typical English mailboxes without attempting log-on.

NOTE: Once at least one account is added, you can run
\`mbsync -a\` to begin downloading mail.

To change an account's password, run \`pass edit your@email.com\`.
EOF
}

while getopts "fpPXlhodTYD:y:i:I:s:S:u:a:n:x:m:t:" o; do case "${o}" in
	l) setact list || exit 1 ;;
	d) setact delete || exit 1 ;;
	D) setact delete || exit 1 ; fulladdr="$OPTARG" ;;
	y) setact sync || exit 1 ; fulladdr="$OPTARG" ;;
	Y) setact sync || exit 1 ;;
	a) setact add || exit 1 ; fulladdr="$OPTARG" ;;
	i) setact add || exit 1 ; imap="$OPTARG" ;;
	I) setact add || exit 1 ; iport="$OPTARG" ;;
	s) setact add || exit 1 ; smtp="$OPTARG" ;;
	S) setact add || exit 1 ; sport="$OPTARG" ;;
	u) setact add || exit 1 ; login="$OPTARG" ;;
	n) setact add || exit 1 ; realname="$OPTARG" ;;
	m) setact add || exit 1 ; maxmes="$OPTARG" ;;
	o) setact add || exit 1 ; type="online" ;;
	P) setact add || exit 1 ; type="pop"; protocol="pop3s" ; iport="${iport:-995}" ;;
	f) setact add || exit 1 ; force=True ;;
	x) setact add || exit 1 ; password="$OPTARG" ;;
	X) setact delete || exit 1 ; purge=True ;;
	t) setact toggle || exit 1 ; cronmin="$OPTARG" ;;
	T) setact toggle || exit 1 ;;
	p) echo "NOTE: Protonmail users must install and configure Protonmail Bridge first for the first sync to work."
		protocol="imap"
		imap="127.0.0.1"
		iport="1143"
		smtp="127.0.0.1"
		sport="1025"
		auth="login"
  		tlsline="tls_fingerprint $(msmtp --serverinfo --host=$smtp --port=$sport --tls --tls-certcheck=off | awk '/SHA256:/ {print $2}')"
		setact add || exit 1
		;;
	*) mwinfo;  exit 1 ;;
esac done

case "$action" in
	list) list ;;
	add) checkbasics && askinfo && getboxes && getprofiles && finalize ;;
	delete) delete ;;
	sync) mailsync $fulladdr ;;
	toggle) togglecron ;;
	*) mwinfo; exit 1 ;;
esac