#!/bin/sh
#
# x-app-open - open remote X app windows on Windows desktop with Cygwin
#
# Copyright (C) 2013 Marko Myllynen <myllynen@redhat.com>
# This program is free software; it is released under the GPLv3.
#
# Installation instructions for Cygwin and this script:
#
# 1) Install from http://www.cygwin.com/ using 32 or 64-bit setup*.exe
# 2) During installation, select at least these additional packages:
#
# keychain openssh psmisc xorg-server xterm
#
# 3) Place this script in C:\cygwin\bin
# 4) Create a shortcut on Windows desktop with
#    a) "Start in" being the bin path 3) above
#    b) "Target" being
#
# C:\cygwin\bin\run.exe -p /bin /bin/sh -c "/bin/x-app-open host application"
#
# In case a user name needs to be specified use the form user@host.
#

SSH_OPTS="-oBatchMode=yes -oConnectTimeout=20 -oStrictHostKeyChecking=no"

# Launch XWin if not there already
XPID=$(ps -ef | grep /bin/XWin | grep -v grep | awk '{print $2}')
if [ "$XPID" = "" ]; then
  run cygstart --hide /bin/XWin :0 -clipboard -multiwindow
  XPID=$(ps -ef | grep /bin/XWin | grep -v grep | awk '{print $2}')
fi
export DISPLAY=$HOSTNAME:0

# Setup SSH keys if needed
while [ ! -f "$HOME/.ssh/id_rsa" ]; do
  xterm +tb -T "Setting up SSH keys..." -e \
    "echo Generating SSH keys, enter a new passphrase, at least 5 characters.;\
      ssh-keygen -f \"$HOME/.ssh/id_rsa\" > /dev/null; \
        echo Copying SSH public key to the remote host...; \
          ssh-copy-id -i \"$HOME/.ssh/id_rsa.pub\" \
            -oStrictHostKeyChecking=no $1 2>&1 | grep -v INFO"
done

# Add SSH keys to ssh-agent with keychain if needed
[[ -f "$HOME/.keychain/$HOSTNAME-sh" ]] && \
  . "$HOME/.keychain/$HOSTNAME-sh" > /dev/null 2>&1
ssh-add -l 2>/dev/null | grep -q "$HOME/.ssh/id_rsa"
if [ $? -ne 0 ]; then
  cygstart --hide xterm +tb -T '"Loading SSH keys..."' -e "keychain -q \"$HOME/.ssh/id_rsa\""
  sleep 3
  while true; do
    sleep 1
    pstree -aA | grep -q -- "[-]xterm +tb -T Loading SSH keys..." || break
  done
  [[ -f "$HOME/.keychain/$HOSTNAME-sh" ]] && \
    . "$HOME/.keychain/$HOSTNAME-sh" > /dev/null 2>&1
fi

# Do the actual work
ssh $SSH_OPTS -X $1 "${@:2}" > /dev/null 2>&1
if [ $? -eq 255 ]; then
  # Connection failed, perhaps a new host, try to copy the key
  xterm +tb -T "Setting up SSH keys..." -e \
    "echo Copying SSH public key to the remote host...; \
      ssh-copy-id -i \"$HOME/.ssh/id_rsa.pub\" \
        -oStrictHostKeyChecking=no $1 2>&1 | grep -v INFO"
  ssh $SSH_OPTS -X $1 "${@:2}" > /dev/null 2>&1
fi

# Terminate XWin if no active connections left
sleep 1
sessions=$(pstree -aA | grep "[s]h $0" | wc -l)
if [ $sessions -le 2 ]; then
  /bin/kill $XPID > /dev/null 2>&1 ; /bin/kill -f $XPID > /dev/null 2>&1
fi