#!/bin/sh
# shellcheck source=/dev/null
#
# pkg - package manager for kiss linux.

die() {
    printf '\033[31mERROR>\033[m %s\n' "$@" >&2
    exit 1
}

log() {
    printf '\033[32m=>\033[m %s\n' "$@"
}

clean() {
    rm -rf "$build_dir" "$pkg_dir"
}

pkg_info() {
    [ -z "$1" ]    && die "No package specified."
    cd "repo/$1"   || die "Package '$1' not in repository."
    [ -f version ] || die "Version file not found."
    [ -f depends ] || die "Depends file not found."
    [ -f sources ] || die "Sources file not found."

    read -r version release < version
    name=$1
    pkg=$name-$version-$release
}

pkg_depends() {
    while read -r dependency; do
        # TODO: Handle dependencies.
        log "Found dependency $dependency"
    done < depends
}

pkg_sources() {
    while read -r source; do
        source_name=${source##*/}

        if [ -f "$source" ]; then
            continue

        elif [ -f "$source_dir/$source_name" ]; then
            log "Found cached $source_name."
            continue

        elif [ -z "${source##*://*}" ]; then
            log "Downloading '$source'."
            wget -P "$source_dir" "$source" || die "Failed to download $source."

        else
            die "Source file '$source' not found."
        fi
    done < sources
}

pkg_extract() {
    while read -r source; do
        source_name=${source##*/}

        if [ -f "$source" ]; then
            cp -f "$source" "$build_dir"

        elif [ -f "$source_dir/$source_name" ]; then
            # TODO: Handle extraction based on file type.
            tar xf "$source_dir/$source_name" -C "$build_dir" \
                --strip-components 1 || die "couldn't extract $source_name"
        fi
    done < sources
}

pkg_build() {
    log "Building $pkg"

    cd "$build_dir"
    set -e
    . "$OLDPWD/build"
    set +e
    cd -

    log "Sucessfully built $pkg"
}

pkg_manifest() {
    cd "$pkg_dir"

    _() { find . -mindepth 1 "$@" | sed 's/^\.//'; }
    _ -not -type d  > "$OLDPWD/manifest"
    _ -type d | sort -r >> "$OLDPWD/manifest"

    cd -
}

args() {
    pkg_info "$2"

    case $1 in
        b*)
            pkg_depends
            pkg_sources
            pkg_extract
            pkg_build
            pkg_manifest
        ;;
    esac
}

main() {
    trap clean EXIT
    clean

    mkdir -p sources build pkg || die "Couldn't create directories at '$PWD'".

    source_dir=$PWD/sources
    build_dir=$PWD/build
    pkg_dir=$PWD/pkg
    sys_dir=$PWD/sys

    args "$@"
}

main "$@"