#!/bin/bash

set -euf -o pipefail

scripts=$(dirname $0)
# shellcheck source=jenkins-helpers.sh
. $scripts/jenkins-helpers.sh

convert_args_to_variables "$@"
shift "$SHIFT_CONVERTED_ARGS"

obligatory_variables \
    artifacts BUILD_URL ci_project ci_config current_project \
    first_bad last_good summary
declare \
    artifacts BUILD_URL ci_project ci_config current_project \
    first_bad last_good summary

dryrun="${dryrun-false}"
icommits="interesting-commits"
verbose="${verbose-true}"

if $verbose; then
    set -x
fi

if $dryrun; then
    dryrun="echo DRYRUN: "
else
    dryrun=""
fi

prepare_interesting_commits ()
{
    (
    set -euf -o pipefail

    # Clone interesting-commits.git repo, which contains a regression
    # summaries for SHA1s.  These are the "first_bad" commits.
    clone_or_update_repo $icommits master \
			 https://git-us.linaro.org/toolchain/ci/interesting-commits.git \
			 auto master
    git_init_linaro_local_remote $icommits baseline false
    )
}

# Update interesting-commit's entry for a given commit
# $1: component
# $2: sha1 of first_bad commit
# $3: sha1 of last_good commit
#
# Interesting-commits store regression history in the following hierarchy:
# 1. At the top level we have COMPONENT directories.
# 2. At the 2nd level we have SHA1 directories.
# 2a. We also have "git describe" symlinks to SHA1 directories for convenience.
# 3. At the 3rd level we have CI_PROJECT directories.
# 4. At the 4th level we have CI_CONFIG directories, and ...
# 4a. ... status.txt, which contains status of changes from SHA1 across all
#     CI_CONFIGs in CI_PROJECT.
# 5. At the 5th level we have per-build files last_good, summary.txt, etc.
update_interesting_entry ()
{
    (
    set -euf -o pipefail

    local component="$1"
    local first_bad="$2"
    local last_good="$3"

    local subdir
    subdir=$(interesting_subdir "$component" "$first_bad")

    local describe
    describe=$(describe_sha1 "$component" "$first_bad" false)

    if ! [ -d $icommits/$subdir ] && [ x"$describe" != x"" ]; then
	local d
	d=$(dirname "$describe")
	mkdir -p $icommits/$component/$d
	local symlink=""
	while [ x"$d" != x"." ]; do
	    symlink="../$symlink"
	    d=$(dirname "$d")
	done
	symlink="${symlink}sha1/$first_bad"
	ln -s $symlink $icommits/$component/$describe
	git -C $icommits add $component/$describe
    fi

    # shellcheck disable=SC2154
    subdir=$(interesting_subdir "$component" "$first_bad" \
				"$ci_project" "$ci_config")
    mkdir -p "$icommits/$subdir"
    echo "$BUILD_URL" > "$icommits/$subdir/build_url"
    echo "$last_good" > "$icommits/$subdir/last_good"
    git -C "$icommits" add "$subdir/build_url" "$subdir/last_good"

    cp $summary "$icommits/$subdir/summary.txt"
    git -C "$icommits" add "$subdir/summary.txt"

    local status="$subdir/../status.txt"
    if [ x"$describe" = x"" ]; then
	describe=$(describe_sha1 "$component" "$first_bad" true)
    fi
    cat > $icommits/$status <<EOF
Status of $describe commit for $ci_project:
$(git -C "$component" log -n1 "$first_bad")
EOF
    local ci_config
    while read ci_config; do
	if ! [ -f "$icommits/$subdir/../$ci_config/summary.txt" ]; then
	    continue
	fi

	echo "* $ci_config"
	(
	    cat $icommits/$subdir/../$ci_config/summary.txt
	    cat $icommits/$subdir/../$ci_config/build_url
	) | sed "s/^/** /"
    done < <(cd $icommits/$subdir/..; ls) >> $icommits/$status
    git -C "$icommits" add "$status"
    )
}

update_interesting_commits ()
{
    (
    set -euf -o pipefail

    # Reset to master branch
    git -C $icommits remote update -p
    git -C $icommits reset -q --hard refs/remotes/baseline/master

    local isubdir
    isubdir=$(interesting_subdir "$current_project" "$first_bad" \
				 "$ci_project")
    local reported_before=false
    if [ -d "$icommits/$isubdir/$ci_config" ]; then
	reported_before=true
    fi

    # We have successfully identified a bad commit with a good parent!
    # Add $first_bad to interesting commits.
    update_interesting_entry "$current_project" "$first_bad" "$last_good"

    # Commit and push
    git -C $icommits commit -m "Add entry $first_bad from ${BUILD_URL-$(pwd)}"
    $dryrun git -C $icommits push baseline HEAD:refs/heads/master

    if $reported_before; then
	# This is a re-occurring problem (usually, in linux-next).
	# Don't spam developers.
	rm -f $artifacts/jira-status.txt $artifacts/mail-recipients.txt
    else
	touch $artifacts/jira-status.txt $artifacts/mail-recipients.txt
    fi
    )
}

# Update mail files with status of $first_bad regression
update_mail_files ()
{
    (
    set -euf -o pipefail

    if ! [ -f $artifacts/mail-recipients.txt ]; then
	return
    fi

    local isubdir
    isubdir=$(interesting_subdir "$current_project" "$first_bad" \
				 "$ci_project")

    sed -e "/#INTERESTING_COMMIT_STATUS#/r $icommits/$isubdir/status.txt" \
	-e "/#INTERESTING_COMMIT_STATUS#/d" \
	< $artifacts/mail-body.draft > $artifacts/mail-body.txt

    cp $artifacts/mail-subject.draft $artifacts/mail-subject.txt
    if [ "$(ls "$icommits/$isubdir" | wc -l)" = 2 ]; then
	cp $artifacts/mail-recipients.draft $artifacts/mail-recipients.txt
    else
	# This is not the first entry for $first_bad in $ci_project --
	# don't notify the patch author.
	# One line for ci_config, and one for status.txt.
	echo "bcc:tcwg-validation@linaro.org" \
	    > $artifacts/mail-recipients.txt
    fi
    )
}

# Post update to Jira
post_to_jira ()
{
    (
    set -euf -o pipefail

    if ! [ -f $artifacts/jira-status.txt ]; then
	return
    fi

    local isubdir
    isubdir=$(interesting_subdir "$current_project" "$first_bad" \
				 "$ci_project")

    sed -e "/#INTERESTING_COMMIT_STATUS#/r $icommits/$isubdir/status.txt" \
	-e "/#INTERESTING_COMMIT_STATUS#/d" \
	< $artifacts/jira-status.draft > $artifacts/jira-status.txt

    if [ -f $HOME/.jipdate.yml ]; then
	echo y | $dryrun jipdate.py -f $artifacts/jira-status.txt
    fi
    )
}

prepare_interesting_commits

while true; do
    update_interesting_commits &
    if wait $!; then
	update_mail_files
	post_to_jira
	break
    fi
done