#!/bin/sh
#
# Copyright © 2008 Mike O'Connor <stew@vireo.org>
#
# This program is free software; you can redistribute it and/or modify it
# under the terms of the GNU General Public License as published by the
# Free Software Foundation; either version 2, 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 General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
# USA.  


set -e

usage() {
    bn=$(basename $0)
    cat <<EOF
$0: manage home directory using mr

NAME
  $bn - a command to manage detached git repositories using mr

SYNOPSIS
  $bn command [options]

  $bn init
  $bn ls
  $bn list
  $bn ls-r
  $bn list-remote
  $bn add repository_name
  $bn new repository_name file1 [file2 file3...]
  $bn login repository_name
  $bn exec repository_name command [arg1 arg2...]

COMMANDS
  init 
      create ~/.moveinrc, create/update  ~/.mrconfig

  ls
  list
      show a list of local repositories

  ls-r
  list-remote
      show a list of remote repositories

  add repository_name
      checkout the repository from the remote host and add it to
      mr's configuration

  new repository_name file1 [file2 file3...]  
      create a new repository on the remote host, and checkin the
      listed files to the new repository.   Add the new repository
      to mr's configuration

  login repository_name
      start a subshell in repository_name

  exec repository_name command [arg1 arg2...]
      execute a command in the context of repository_name, for example:
        $bn exec myrepo git status
        $bn exec myrepo git ls-files

EOF

    exit 1
}

[ $# -ge 1 ] || usage

GIT_HOST=git.vireo.org
REMOTE_REPOS=~/git
LOCAL_REPOS=~/.movein
MRCONFIG=~/.mrconfig
MOVEINRC=~/.moveinrc

[ -e "$MOVEINRC" ] && . "$MOVEINRC"

init() {

    if [ $# -ne 0 ]; then 
	usage
    fi
    
    if [ -e $MOVEINRC ]; then
	echo $MOVEINRC already exists
	exit 1
    fi

    echo -n "git server hostname? [git.vireo.org] " 
    read GIT_HOST
    if [ -z "$GIT_HOST" ]; then 
	GIT_HOST=git.vireo.org
    fi

    echo -n "path to remote repositories? [~/git] " 
    read REMOTE_REPOS
    if [ -z "$REMOTE_REPOS" ]; then 
	REMOTE_REPOS=~/git
    fi

    echo -n "Local repository directory? [~/.movein] " 
    read LOCAL_REPOS
    if [ -z "$LOCAL_REPOS" ]; then 
	LOCAL_REPOS=~/.movein
    fi

    echo -n "Location of .mrconfig file? [~/.mrconfig] " 
    read MRCONFIG
    if [ -z "$MRCONFIG" ]; then 
	MRCONFIG=~/.mrconfig
    fi

    cat <<EOF > $MOVEINRC
GIT_HOST=$GIT_HOST
REMOTE_REPOS=$REMOTE_REPOS
LOCAL_REPOS=$LOCAL_REPOS
MRCONFIG=$MRCONFIG
EOF

    if [ ! -d "$LOCAL_REPOS" ]; then 
	mkdir -p "$LOCAL_REPOS"
    fi

    mr -c "$MRCONFIG" config DEFAULT include="cat /usr/share/mr/git-fake-bare"
    
}

login() {
    if [ $# -ne 1 ]; then 
	usage
    fi

    export GIT_DIR="$LOCAL_REPOS/${1}.git"
    export GIT_WORK_TREE="$GIT_DIR/$(git config --get core.worktree)"

    GIT_PS1_SHOWUNTRACKEDFILES= PSMOVEIN="movein:${1}" $SHELL -i || :
}

execin() {
    local REPO
    if [ $# -lt 1 ]; then
	usage
    fi

    REPO=$1;shift

    export GIT_DIR="$LOCAL_REPOS/${REPO}.git"
    export GIT_WORK_TREE="$GIT_DIR/$(git config --get core.worktree)"

    "$@"
}

add() {
    if [ $# -ne 1 ]; then 
	usage
    fi
    REPO_NAME=$1.git ; shift
    LOCAL_REPO=$LOCAL_REPOS/$REPO_NAME
    REPO_URL=ssh://$GIT_HOST/$REMOTE_REPOS/$REPO_NAME

    if [ -e "$LOCAL_REPO" ]; then
	echo $LOCAL_REPO already exists
	exit 1
    else
	trap "rm -rf $LOCAL_REPO" 0
	mkdir "$LOCAL_REPO"
	export GIT_DIR="$LOCAL_REPO"
	git init --bare
	git remote add origin $REPO_URL
	git config branch.master.remote origin
	git config branch.master.merge refs/heads/master
	git config core.bare false
	git config core.worktree ../../
	git config status.showUntrackedFiles no
	GIT_WORK_TREE="$LOCAL_REPO/../../" git pull
	trap - 0

	mr -c "$MRCONFIG" config "$LOCAL_REPO" checkout="git_fake_bare_checkout '$REPO_URL' 'REPO_NAME' '../../'"
    fi
}

list() {
    find "${LOCAL_REPOS}" -mindepth 1 -maxdepth 1 -type d | sed 's,^.*/\([^/]*\).git$,\1,'
}

listremote() {
    ssh $GIT_HOST "
        find '${REMOTE_REPOS}' -mindepth 1 -maxdepth 1 -type d | sed 's,^.*/\([^/]*\).git$,\1,'
    " </dev/null
}

new() {
    if [ $# -lt 2 ]; then 
	usage
    fi
    REPO_NAME=$1.git ; shift
    LOCAL_REPO="$LOCAL_REPOS/$REPO_NAME"
    REPO_URL="ssh://$GIT_HOST/$REMOTE_REPOS/$REPO_NAME"

    if [ ! -e "$1" ]; then
	echo $1 not found
	exit 1
    fi

    if [ -e "$LOCAL_REPO" ]; then
	echo $LOCAL_REPO already exists
	exit 1
    else
	trap "rm -rf $LOCAL_REPO" 0
	mkdir -p "$LOCAL_REPO"

	ssh $GIT_HOST "
               GIT_DIR=$REMOTE_REPOS/$REPO_NAME git --bare init
        " </dev/null

	export GIT_DIR="$LOCAL_REPO"
	git init --bare
	git remote add origin $REPO_URL
	git config branch.master.remote origin
	git config branch.master.merge refs/heads/master
	git config core.bare false
	git config core.worktree ../../
	git config status.showUntrackedFiles no
	export GIT_WORK_TREE="$LOCAL_REPO/../../"
	git add "$@"
	git commit -m "initial checkin"
	git push --all
	
	trap - 0

	mr -c "$MRCONFIG" config "$LOCAL_REPO" checkout="git_fake_bare_checkout '$REPO_URL' 'REPO_NAME' '../../'"
    fi

}


command=$1 ; shift
case "$command" in 
    init)
	init $@
	;;
    add)
	add $@
	;;
    new)
	new $@
	;;
    login)
	login $@
	;;
    exec)
	execin "$@"
	;;
    ls)
	list
	;;
    list)
	list
	;;
    ls-r)
	listremote
	;;
    list-remote)
	listremote
	;;

    *)
	usage
	exit 1
	;;
esac