#!/bin/bash -e

SCRIPT_PATH="$(dirname "$0")"
APK_FILE=/apks.txt

function is_newer() {
    local url="$1"
    local remote_date local_date
    local headers; headers="$(curl -sSLI "$url")"
    local file; file="$(grep -Po '(?<=filename=).*\.apk' <<< "$headers")"

    if ! [ -f "$file" ]; then
        return 0
    fi
    remote_date="$(sed -n 's/last-modified: //p' <<< "$headers")"
    local_date="$(stat "$file" | sed -n 's/^Modify: //p')"
    [ "$(date -d "$remote_date" '+%s')" -gt "$(date -d "$local_date" '+%s')" ]
}

function filter_links() {
    links=()

    for link in "$@"; do
        if is_newer "$link"; then
            links+=("$link")
        fi
    done
    echo "${links[@]}"
}

function get_links() {
    local file="$1"
    local url
    local tag
    local line

    while read -r line; do
        IFS=' ' read -r url tag <<< "$line"

        case "$url" in
            *github.com/*)
                "$SCRIPT_PATH/get_github_dl_links.sh" "$url" "$tag"
                ;;
            *gitlab.com/*)
                "$SCRIPT_PATH/get_gitlab_dl_links.sh" "$url" "$tag"
                ;;
            *)
                ;;
        esac
    done < <(awk 'NF && $1!~/^#/' "$file" | sort -u)
}

function main() {
    local links

    readarray -t links < <(get_links "$APK_FILE" | sort -u)
    read -ra links < <(filter_links "${links[@]}")

    (cd /repo/repo/ && xargs -n1 -P8 curl -sSLO <<< "${links[@]}")
    (cd /repo/ && fdroid update -c)

    if [ -n "$PUID" ]; then
        chown -R "$PUID:$PGID" /repo/
    fi
}

main "$@"