# Check either a package is installed or not
#
# example: ynh_package_is_installed 'yunohost' && echo "ok"
#
# usage: ynh_package_is_installed name
# | arg: name - the package name to check
ynh_package_is_installed() {
    dpkg-query -W -f '${Status}' "$1" 2>/dev/null \
        | grep -c "ok installed" &>/dev/null
}

# Get the version of an installed package
#
# example: version=$(ynh_package_version 'yunohost')
#
# usage: ynh_package_version name
# | arg: name - the package name to get version
# | ret: the version or an empty string
ynh_package_version() {
    if ynh_package_is_installed "$1"; then
        dpkg-query -W -f '${Version}' "$1" 2>/dev/null
    else
        echo ''
    fi
}

# APT wrapper for non-interactive operation
#
# usage: ynh_apt update
ynh_apt() {
    DEBIAN_FRONTEND=noninteractive sudo apt-get -y -qq $@
}

# Update package index files
#
# usage: ynh_package_update
ynh_package_update() {
    ynh_apt update
}

# Install package(s)
#
# usage: ynh_package_install name [name [...]]
# | arg: name - the package name to install
ynh_package_install() {
    ynh_apt -o Dpkg::Options::=--force-confdef \
            -o Dpkg::Options::=--force-confold install $@
}

# Remove package(s)
#
# usage: ynh_package_remove name [name [...]]
# | arg: name - the package name to remove
ynh_package_remove() {
    ynh_apt remove $@
}

# Remove package(s) and their uneeded dependencies
#
# usage: ynh_package_autoremove name [name [...]]
# | arg: name - the package name to remove
ynh_package_autoremove() {
    ynh_apt autoremove $@
}

# Build and install a package from an equivs control file
#
# example: generate an empty control file with `equivs-control`, adjust its
#          content and use helper to build and install the package:
#              ynh_package_install_from_equivs /path/to/controlfile
#
# usage: ynh_package_install_from_equivs controlfile
# | arg: controlfile - path of the equivs control file
ynh_package_install_from_equivs () {
    controlfile=$1

    # Check if the equivs package is installed. Or install it.
    ynh_package_is_installed 'equivs' \
        || ynh_package_install equivs

    # retrieve package information
    pkgname=$(grep '^Package: ' $controlfile | cut -d' ' -f 2)	# Retrieve the name of the debian package
    pkgversion=$(grep '^Version: ' $controlfile | cut -d' ' -f 2)	# And its version number
    [[ -z "$pkgname" || -z "$pkgversion" ]] \
        && echo "Invalid control file" && exit 1	# Check if this 2 variables aren't empty.

    # Update packages cache
    ynh_package_update

    # Build and install the package
    TMPDIR=$(ynh_mkdir_tmp)
    cp "$controlfile" "${TMPDIR}/control" && pushd "$TMPDIR"	# pushd is like a cd, but it stores the previous directory
    # Create a fake deb package with equivs-build and the given control file
    # Install the fake package without its dependencies with dpkg
    # Install missing dependencies with ynh_package_install
    equivs-build ./control 1>/dev/null \
     && sudo dpkg --force-depends \
          -i "./${pkgname}_${pkgversion}_all.deb" 2>&1 \
     && ynh_package_install -f
    [[ -n "$TMPDIR" ]] && rm -rf $TMPDIR	# Remove the temp dir.

    # check if the package is actually installed
    ynh_package_is_installed "$pkgname"
    popd	# Like a cd on the directory stored by pushd
}

# Install dependencies with a equivs control file
#
# usage: ynh_app_dependencies dep [dep [...]]
# | arg: dep - the package name to install in dependence
ynh_app_dependencies () {
	dependencies=$1
	version=$(sudo python3 -c "import sys, json;print(json.load(open('../manifest.json'))['version'])")	# Retrieve the version number in the manifest file.
    dep_app=${app/_/-}	# Replace all '_' by '-'
    cat > ./${dep_app}-ynh-deps.control << EOF	# Make a control file for equivs-build
Section: misc
Priority: optional
Package: ${dep_app}-ynh-deps
Version: ${version}
Depends: ${dependencies}
Architecture: all
Description: Fake package for ${app} (YunoHost app) dependencies
 This meta-package is only responsible of installing its dependencies.
EOF
    ynh_package_install_from_equivs ./${dep_app}-ynh-deps.control \
        || ynh_die "Unable to install dependencies"	# Install the fake package and its dependencies
}

# Remove fake package and its dependencies
#
# Dependencies will removed only if no other package need them.
#
# usage: ynh_remove_app_dependencies
ynh_remove_app_dependencies () {
    dep_app=${app/_/-}	# Replace all '_' by '-'
    ynh_package_autoremove ${dep_app}-ynh-deps	# Remove the fake package and its dependencies if they not still used.
}