#!/bin/bash

if [ $# -lt 2 ]
then
	echo "USAGE: $0 <git-ref-1> <git-ref-2>"
	echo "Ex: $0 v0.14.0-a2 v0.14.0-a3"
	echo "Ex: $0 f9af2a72 master"
	exit 1
fi

# 1. Get git log between the requested commits
# 2. Get lines +2 after date and bug. This pulls in the commit heading which shows 2nd line after date and all Bug: lines
# 3. Get rid of anything not relevant from output of 2.
# 4. Initial sed processing to strip whitespace, add "* " on all lines except "Bug: " lines, convert "Bug: " lines to [[phab: ..]] links
#    - In the edge case that a commit heading starts with a %, the "* " will not be appended.
# 5. Further sed processing to collapse phab links onto previous lines
git log $1..$2 | egrep -A+2 "^\s*(Date|Bug):\s*" | egrep -v "Change-Id:|Depends-On:|Date:|--|^\n*$" | sed 's/^[ \t]*//g;s/^Bug:/%%%:/g;s/^[^%]/* &/g;s/%%%:\s*\(.*\)/[[phab:\1|\1]]/g;' | sed -e ':a' -e 'N;$!ba' -e 's/\n*\[\[phab/, [[phab/g;'

# You will have to edit this output to:
# 1. switch up the commit heading and phab numbers (if you want to follow the current format on [[mw:Parsoid/Deployments]])
# 2. get rid of any commit summaries not relevant to the deployment summary (unless we decide we no longer care about that and it is simpler to just dump this output there)