# Alerts, for when user needs to read something.
alert() {
    play -qnV0 synth 3 pluck D3 pluck A3 pluck D4 pluck F4 pluck A4 delay 0 .1 .2 .3 .4 remix - chorus 0.9 0.9 38 0.75 0.3 0.5 -t
    echo
    read -rp "Press enter to continue." continue
}

check_requirements() {
    # Make sure the minimum of curl, sox, wine, and winetricks are installed or fex-emu on aarch64
    if [[ "$(uname -m)" == "aarch64" ]]; then
        minimumDependencies=("FEXLoader")
        wine="FEXLoader -- /usr/bin/wine"
    else
        minimumDependencies=("curl" "sox" "wine")
    fi
    for i in "${minimumDependencies[@]}" ; do
        if ! command -v $i &> /dev/null ; then
            echo "Please install $i before continuing."
            return 1
        fi
    done
    return 0
}

download() {
   local source=($@)
   for i in "${source[@]}" ; do
       local dest="${i##*/}"
       dest="${dest//%20/ }"
       dest="${dest#*\?filename=}"
       dest="${dest%\?*}"
       # Remove the destination file if it is empty.
       [[ -s "${cache}/${dest}" ]] || rm -f "${cache}/${dest}" 2> /dev/null
       if [[ "${redownload}" == "true" ]] && [[ -e "${cache}/${dest}" ]]; then
           rm -v "${cache}/${dest}"
       fi
       # Skip if the item is in cache.
       [[ -e "${cache}/${dest}" ]] && continue
       { if ! curl -L4 -C - --retry 10 --output "${cache}/${dest}" "${i}" ; then
           echo "Could not download \"$i\"..."
           exit 1
       fi; } | dialog --backtitle "Audio Game Manager" \
           --progressbox "Downloading \"$dest\" from \"$i\"" -1 -1
       local downloadError=1
       case "${dest##*.}" in
           "pk3"|"zip")
               unzip -tq "${cache}/${dest}"  | dialog --backtitle "Audio Game Manager" \
                   --progressbox "Validating ${dest##*.} file" -1 -1 --stdout
                   downloadError=$?
           ;;
           "7z")
               7z t "${cache}/${dest}" | dialog --backtitle "Audio Game Manager" \
                   --progressbox "Validating 7z file" -1 -1 --stdout
                   downloadError=$?
           ;;
           "exe")
               # Check if it's a valid Windows executable by looking at the MZ header
               hexdump -n 2 -v -e '/1 "%02X"' "${cache}/${dest}" | grep -q "4D5A"
                   downloadError=$?
           ;;
           "wad")
               if [[ "$(file -b --mime-type "${cache}/${dest}")" != "application/octet-stream" ]]; then
                   downloadError=0
               fi
           ;;
           *)
               # Add HTML check for other file types
               if file -b "${cache}/${dest}" | grep -q "HTML document" ; then
                   echo "File not found: \"$i\" (HTML document probably 404)"
                   downloadError=1
               else
                   downloadError=0
               fi
           ;;
       esac
       if [[ $downloadError -ne 0 ]]; then
           rm -fv "${cache}/${dest}"
                   dialog --backtitle "Audio Game Manager" \
                       --infobox "Error downloading \"${dest}\". Installation cannot continue." -1 -1 --stdout
                   alert
                   exit 1
       fi
   done
}

# Function to open urls across OS.
open_url() {
    if [[ "$(uname)" == "Darwin" ]]; then
        open "${*}" 2> /dev/null
    else
        xdg-open "${*}" 2> /dev/null
    fi
}