#!/bin/bash

# Copyright (c) 2015, Intel Corporation
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
#     * Redistributions of source code must retain the above copyright notice,
#       this list of conditions and the following disclaimer.
#     * Redistributions in binary form must reproduce the above copyright
#       notice, this list of conditions and the following disclaimer in the
#       documentation and/or other materials provided with the distribution.
#     * Neither the name of Intel Corporation nor the names of its contributors
#       may be used to endorse or promote products derived from this software
#       without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

function usage() {
    echo "Usage: $0 SHA1_DB sha1 (add version path upstream | add_git git_repo binary_path | read_attr (version | path | upstream | \$attr) | write_attr \$attr \$value)"

    exit $1
}

function exit_error() {
    echo $@
    exit 1
}

function db_get_file() {
    sha1_db=$1
    sha1=$2

    echo "$sha1_db/db/$sha1"
}

function db_add() {
    sha1_db=$1
    sha1=$2
    version=$3
    path=$4
    upstream=$5

    sha1_db_file=$(db_get_file $sha1_db $sha1)
    if [ -f $sha1_db_file ]
    then
        orig_path=$(db_read $sha1_db $sha1 path)
        echo "SHA1_DB: The SHA1 $sha1 already exists (orig=$orig_path vs new=$path), exit..."
        exit 0
    fi

    mkdir -p $(dirname $sha1_db_file) 2> /dev/null

    echo "SHA1_DB_VERSION=1" > $sha1_db_file
    echo "version=$version" >> $sha1_db_file
    echo "path=$path" >> $sha1_db_file
    echo "upstream=$upstream" >> $sha1_db_file

    echo "SHA1_DB: '$path' ($sha1) add under version=$version, upstream=$upstream"

    exit 0
}

function db_add_git() {
    sha1_db=$1
    sha1=$2
    git_repo=$3
    binary=$4

    if [ "$sha1" == "-" ]
    then
        sha1=$(sha1sum $binary | cut -d ' ' -f 1)
    fi

    pwd=$(pwd)
    cd $git_repo 2> /dev/null || exit_error "Error: cannot open the folder '$git_repo'."
    git status > /dev/null 2>&1 || exit_error "Error: the folder '$git_repo' is not a git repo."

    git_sha1=$(git rev-parse --short HEAD)
    tracked_branch=$(git branch -vv --no-color | grep --color=never "^*" | cut -d '[' -f 2 | cut -d ']' -f 1 | cut -d : -f 1)
    remote=$(echo "$tracked_branch" | cut -d '/' -f 1)
    branch=$(echo "$tracked_branch" | cut -d '/' -f 2)

    # handle local branches by just using the local
    if [ -n "$(echo "$branch" | grep " ")" ]
    then
        # Local branch detected
        fetch_url="$USER@$(hostname):$(pwd)"
        branch=$(git rev-parse --abbrev-ref HEAD)
    else
        fetch_url=$(git remote show -n origin | grep "Fetch URL:" | cut -d ':' -f 2- | cut -d ' ' -f 2-)
    fi
    cd $pwd

    db_add "$sha1_db" "$sha1" "$git_sha1" "$binary" "$fetch_url/$branch"
}

function db_read() {
    sha1_db=$1
    sha1=$2
    attribute=$3

    sha1_db_file=$(db_get_file $sha1_db $sha1)
    [ ! -f $sha1_db_file ] && exit 1

    value=$(grep $attribute $sha1_db_file | cut -d '=' -f 2-)
    [ -z "$value" ] && exit 1

    echo $value
    exit 0
}

function db_write() {
    sha1_db=$1
    sha1=$2
    attribute=$3
    value=$4

    sha1_db_file=$(db_get_file $sha1_db $sha1)
    [ ! -f $sha1_db_file ] && exit 1

    existing_value=$(grep $attribute $sha1_db_file | cut -d '=' -f 2-)
    if [ -z "$value" ]
    then
        # add the value
         echo "$attribute=$value" > $sha1_db_file
    else
        #replace the value
        sed -i "s~$attribute=$existing_value~$attribute=$value~g" $sha1_db_file
    fi
    exit 0
}

if [[ $# -lt 4 ]]
then
    usage 1
fi

sha1_db=$1
sha1=$2
action=$3

case "$action" in
    add)
       if [[ $# -ne 6 ]]
       then
           usage 1
       fi
       version=$4
       path=$5
       upstream=$6
       db_add "$sha1_db" "$sha1" "$version" "$path" "$upstream"
       ;;

    add_git)
        if [[ $# -ne 5 ]]
        then
            usage 1
        fi
        git_repo=$4
        binary=$5
        db_add_git "$sha1_db" "$sha1" "$git_repo" "$binary"
        ;;
    read_attr)
       attribute=$4
       db_read "$sha1_db" "$sha1" "$attribute"
       ;;
    write_attr)
        if [[ $# -ne 5 ]]
       then
           usage 1
       fi
       attribute=$4
       value=$5
       db_write "$sha1_db" "$sha1" "$attribute" "$value"
       ;;
    *) echo "SHA1_DB: invalid action '$action'"
       ;;
esac