#!/bin/sh

. $(dirname $0)/adc.common-functions

# Copyright 2010 Massachusetts Institute of Technology
#
# Licensed under the MIT license: http://www.opensource.org/licenses/mit-license.php

# This "watch" ADC can be used to maintain a list of watchers to a
# repository. You can then perform actions on the watchlist from a
# hook or ADC.
#
# An obvious function of this would be to maintain a list of email
# addresses that are sent commit notifications. There are however
# unlimited uses, such as:
#
# * Specifying Twitter accounts that should receive notifications
#   of new clones created via the "fork" ADC
# * Specifying hostnames of machines that should be poked to update
#   their repository web views
# * Etc...
#
# The parameters are the repository path, "add"/"remove", and the
# identifier. These are added along with your system identifier to a 
# gl-watchers file. However, there is an optional argument that allows you
# specify what the identifier is used for. This allows you to perform
# a default action if there is no optional argument, or a specific action
# depending on what the optional argument. For instance, the gl-watchers
# file on the server might look like this (note the actions described would
# only occur if you actually code it in!):
# 
# mitchell  mitchell@kde.org [no optional argument; would default to email]
# mitchell  mitchell@kde.org email [will send email on pushes]
# mitchell  projects.kde.org httppost [will send commit details in an
#                                      HTTP POST to proejcts.kde.org]
#
#
# Note that there is no authentication here; any user is allowed to
# set any identifier, although users can only modify their own
# identifiers. (This applies of course only to repositories a user can read
# in the first place!) This script can easily be modified to only allow only
# administrators (those with write access to the gitolite
# administration repository) to add or remove watchers. See the
# commented code below; uncomment it to enable this functionality.

# Adminstrators can use the "sudo" ADC to add entries for specific
# users.

# Uncomment this and comment the corresponding block below to 
# restrict this functionality to administrators only
#get_rights_and_owner gitolite-admin
#[ -z "$perm_write" ] && die "just *what* are you trying to pull, young man?"
#get_rights_and_owner $1;

# all the can_* functions set $repo
can_read $1 || die "no read permissions on $repo"

cmd=$2
identifier=$3
arg=$4
[ -z "$cmd" -o -z "$identifier" -o "$cmd" != "add" -a "$cmd" != "remove" ] && die "paramters must be <repopath> <add|remove> <identifier> <optional argument>"

if [ ! -z "$arg" ]
  then
    identarg="$identifier $arg"
  else
    identarg="$identifier"
fi

cd $GL_REPO_BASE_ABS/$repo.git
[ ! -e gl-watchers ] && { touch gl-watchers || die "cannot create blank watchers file"; }
[ ! -r gl-watchers ] && die "cannot read watchers file"

grep "^$GL_USER $identarg$" gl-watchers > /dev/null
found=$?

[ $found -eq 0 -a $cmd == "add" ] && die "There is already a watch \"$identarg\" for user $GL_USER"
[ $found -ne 0 -a $cmd == "remove" ] && die "No watch \"$identarg\" found for user $GL_USER"

[ $cmd == "add" ] && echo "$GL_USER $identarg" >> gl-watchers && { echo "Added a watch \"$identarg\" for user $GL_USER"; exit 0; }

[ $cmd == "remove" ] && sed -i -e "/^$GL_USER $identarg$/d" gl-watchers && { echo "Removed a watch \"$identarg\" for user $GL_USER"; exit 0; }

die "16 cores, 320GB of RAM, 4TB of disk, and you give me a command I am not programmed to do. Humans..."