# This software is a part of ISAR.
# Copyright (C) 2017-2018 Mixed-Mode GmbH
#
# This class implements common functionality for the apt cache.
#
# Todo:
# 1. When a function of this API return an error, bitbake should output the last function produced the error!
#
# 2. Add functionality of creating snapshots of local isar repo.
#
#
CFG_FILE = "${CACHE_CONF_DIR}/${CACHE_CFG_FILE}"
MIRROR = "${DISTRO_SUITE}-mirror"
SNAPSHOT_BASENAME="snapshot"
ISAR_REPO_LOCAL = "isar-repo-local"
ISAR_FIRST_BUILD_DONE = "${TMPDIR}/first_build_done"

# Reproducible build is not default
ISAR_REPRODUCIBLE_BUILD ?= "1"


# Rename a snapshot
# $1: Old name.
# $2: New name.
_rename_snapshot() {
	aptly -config=${CFG_FILE} snapshot rename $1 $2
}


# Create a new repository database for Isar generated packages.
# $1: Repository database name
_repo_db_create() {
    aptly -config=${CFG_FILE} \
          repo create \
          -component="main" \
          -distribution="${DISTRO_SUITE}" \
          $1
}


# Drop a created repository database silenty.
_repo_db_drop() {
    aptly -config=${CFG_FILE} \
          repo drop \
          $1 || bbwarn "drop db failed"

}


# Add packages to the local repository database.
# $1: Repository database name.
# $*: Packages to add.
_repo_db_add_package() {
    repo=$1
    shift
    aptly -config=${CFG_FILE} repo add -force-replace $repo $*
}


# Delete packages from the repository database.
# $1: Repository database name.
# $*: Packages to delete.
_repo_db_delete_package() {
    #
    # Todo: Remove from pool? But maybe this is required for snapshots?
    # We have build fragments saved at the pool! That is good.
    #
    # After 3 rebuilds:
    #
    #./public/isar/pool/main/s/swupdate/swupdate_1.0_armhf.deb
    #./pool/df/88/702fa609fbd90b735d7cdb6dfeef_swupdate_1.0_armhf.deb
    #./pool/f0/6e/21d09a07366d7f9f7f6690ea7656_swupdate_1.0_armhf.deb
    #./pool/bd/c3/974c8903d41666d23239a8330627_swupdate_1.0_armhf.deb

    repo=$1
    shift
    aptly -config=${CFG_FILE} repo remove $repo $*
}


# Publish repository consumed by apt. This function can only be called
# for repositories
# $1: Repository database name
# $2: Path Prefix
_repo_db_publish(){
    aptly -config=${CFG_FILE} \
          publish repo \
          -architectures="${DEB_HOST_ARCH},${DISTRO_ARCH}" \
          $1 \
          $2

}


# Drop an already published repository.
# $1: Path prefix
_repo_db_publish_drop() {
    aptly -config=${CFG_FILE} \
          publish drop \
          ${DISTRO_SUITE} \
          $1 || bbwarn "drop published failed"
}


# Switch already published repository to new repository. This
# will change the content of the published repository. This function
# can only be called on published repos.
# $1: Prefix.
_repo_db_published_update() {
    aptly -config=${CFG_FILE} \
          publish update \
          -force-overwrite \
          ${DISTRO_SUITE} $1
}


# Add packages to the isar cache.
# $1: Repository database name.
# $2: Repository prefix
# $*: Packages to add.
cache_add_package() {
    repo=$1
    prefix=$2
    shift 2
    _repo_db_add_package $repo $*
    _repo_db_published_update $prefix
}


# Delete a package from the apt cache.
# This function is used to be called within do_clean(all) task.
# $1: Repository database name.
# $2: Repository prefix
# $*: Packages to delete.
cache_delete_package() {
    repo=$1
    prefix=$2
    shift 2
    _repo_db_delete_package $repo $*
    _repo_db_published_update $prefix
}


cache_create_snapshot() {
    aptly -config=${CFG_FILE} \
          snapshot create ${SNAPSHOT_BASENAME}_${DATETIME} from repo ${ISAR_REPO_LOCAL}
}


cache_load_snapshot() {
  "${FUNCNAME[1]} not implemented."
}

# Setup the apt cache, only if no cache is available, yet.
do_cache_setup() {
    set -E
    _cleanup() {
        ret=$?
        bbwarn "Error in apt-cache.bblcass: ${BASH_SOURCE[0]}: (Line ${BASH_LINENO[0]}, Func:${FUNCNAME[1]})"
        (exit $ret) || bb_exit_handler
    }
    trap '_cleanup' ERR

    # Very first build of isar. Setting up the cache.
    if [ ! -e "${CFG_FILE}" ]; then
        bbplain "Creating local apt cache for first build."
        sed -e 's|##CACHE_DIR##|${CACHE_DIR}|' \
            ${FILESDIR}/${CACHE_CFG_FILE}.in > ${CFG_FILE}

        _repo_db_create ${ISAR_REPO_LOCAL} ${ISAR_CACHE_LOCAL_PREFIX}
        _repo_db_publish ${ISAR_REPO_LOCAL} ${ISAR_CACHE_LOCAL_PREFIX}
    fi


    if [ -e "${ISAR_FIRST_BUILD_DONE}" ] && [ "${REPRODUCIBLE_BUILD_ENABLED}" == "1" ]; then
        bbplain "Reusing last apt cache snapshot: $(aptly --config=${CFG_FILE} --raw -sort=time snapshot list | tail -n 1)"
        return
    fi

    #bbwarn "Republishing repo of last build"
    #_repo_db_publish_drop ${ISAR_CACHE_LOCAL_PREFIX}
    #_repo_db_drop ${ISAR_REPO_LOCAL}
    #_repo_db_create ${ISAR_REPO_LOCAL} ${ISAR_CACHE_LOCAL_PREFIX}
    #_repo_db_publish ${ISAR_REPO_LOCAL} ${ISAR_CACHE_LOCAL_PREFIX}

}
addtask do_cache_setup before do_rootfs
do_cache_setup[dirs] += "${CACHE_CONF_DIR}"
do_cache_setup[lockfiles] = "${DPKG_LOCK}"