#!/bin/bash

# Load params as local variables
for kv in $*; do
    [[ $kv =~ ^.*=.*$ ]] && eval $kv
done

[[ -z $GIT_SSH_URL ]] && echo "missing env GIT_SSH_URL" && exit 1
[[ -z $GIT_BRANCH ]] && echo "missing env GIT_BRANCH" && exit 1
[[ -z $GIT_SSH_KEY_FILE ]] && echo "missing env GIT_SSH_KEY_FILE" && exit 1
[[ -z $FLATNOTES_ROOT ]] && echo "missing env FLATNOTES_ROOT" && exit 1
[[ ! -e $FLATNOTES_ROOT ]] && echo "flatnotes directory does not exist" && exit 1
[[ ! -e $GIT_SSH_KEY_FILE ]] && echo "ssh key file not found" && exit 1

CHANGELOG="[flatnotes] Changelog.md"

cd $FLATNOTES_ROOT

git_bin=$(which git)
function git
{
    echo "[$(basename $0)] exec cmd: git $*"
    $git_bin $*
}

function build_changelog
{
    echo "| Date | Commit | Message |"
    echo "| --- | --- | --- |"
    $git_bin -C $FLATNOTES_ROOT log --date=iso --pretty=format:'| %ad | %h | %s |' $GIT_BRANCH
}

function url_parser {
    url=$1

    protocol=$(echo "$1" | grep "://" | sed -e's,^\(.*://\).*,\1,g')
    url_no_protocol=$(echo "${1/$protocol/}")
    protocol=$(echo "$protocol" | tr '[:upper:]' '[:lower:]' | cut -d: -f1)
    userpass=$(echo "$url_no_protocol" | grep "@" | cut -d"/" -f1 | rev | cut -d"@" -f2- | rev)
    pass=$(echo "$userpass" | grep ":" | cut -d":" -f2)
    if [ -n "$pass" ]; then
      user=$(echo "$userpass" | grep ":" | cut -d":" -f1)
    else
      user="$userpass"
    fi
    hostport=$(echo "${url_no_protocol/$userpass@/}" | cut -d"/" -f1)
    host=$(echo "$hostport" | cut -d":" -f1)
    port=$(echo "$hostport" | grep ":" | cut -d":" -f2)
    path=$(echo "$url_no_protocol" | grep "/" | cut -d"/" -f2-)

    export url_parser_proto=$protocol
    export url_parser_user=$user
    export url_parser_host=$host
    export url_parser_port=$port
}

function ssh_init
{
    mkdir -p $HOME/.ssh && chmod 700 $HOME/.ssh
    touch $HOME/.ssh/config
    chmod 600 $HOME/.ssh/config
    cp $GIT_SSH_KEY_FILE $HOME/.ssh/privkey
    chmod 400 $HOME/.ssh/privkey

    echo "
    Host $url_parser_host
        IdentityFile $HOME/.ssh/privkey
        User $url_parser_user
        Port $url_parser_port
        UserKnownHostsFile /dev/null
        StrictHostKeyChecking no
    " > $HOME/.ssh/config
}

function git_init
{
    git config --global user.name "Flatnotes"
    git config --global user.email "flatnotes@autocommit"
    git config --global --add safe.directory $FLATNOTES_ROOT
    git config --global pull.rebase true

    if [[ ! -d ${FLATNOTES_ROOT}/.git ]]; then
        echo ".flatnotes" > ${FLATNOTES_ROOT}/.gitignore
        echo $CHANGELOG | sed -e 's, ,*,g' -re 's,(\[|\]),\\\1,g' >> ${FLATNOTES_ROOT}/.gitignore
        git init
        git branch -m $GIT_BRANCH
        git remote add origin $GIT_SSH_URL
        git fetch && git reset --hard origin/$GIT_BRANCH
    else
        git remote set-url origin $GIT_SSH_URL
        git branch -m $GIT_BRANCH
        git branch --set-upstream-to=origin/$GIT_BRANCH $GIT_BRANCH
        # update
        autocommit_on_event "fake" "ACCESS" "fake"

    fi
}

function start_inotify
{
    inotifywait -q -m $FLATNOTES_ROOT -e access -e modify -e create -e delete  | \
    while read -r directory action file; do
        if [[ "$file" == "$CHANGELOG" ]]; then
            echo "$CHANGELOG modified, skip"
        elif [[ "$file" =~ .*md$ || "$directory" == "${FLATNOTES_ROOT}/attachments" ]]; then
            echo "[inotifywait] event catched action=$action on directory=$directory file=$file"
            autocommit_on_event "$directory" "$action" "$file"
            build_changelog > "${FLATNOTES_ROOT}/${CHANGELOG}"
            sleep 1
        fi
    done
}

function autocommit_on_event
{
    directory="$1"
    action="$2"
    file="$3"

    local_change=$(git status --short  | wc -l)

    if [[ $action == ACCESS ]]; then
        # update local repo in case some file has been updated by other method than flatnotes
        [[ $local_change > 0 ]] && git stash save -a local_changes
        git pull -X ours
        [[ $local_change > 0 ]] && git stash pop && git stash clear
    else
        [[ $local_change == 0 ]] && echo "autocommit_on_event: nothing to commit" && return
        git add --all
        git commit -m "Autocommit action=$action on file=$file detected"
        git push
    fi
}

url_parser $GIT_SSH_URL
if [[ $url_parser_proto != ssh ]]; then
    echo "Need a git ssh url"
    exit 1
fi
ssh_init
git_init
start_inotify