#!/bin/bash

### @accetto, September 2022
### updated: January 2023

echo -e "\n==> EXECUTING @$(date -u +'%Y-%m-%d_%H-%M-%S'): ${0} $@\n"

declare _mydir=$(dirname $0)

source "${_mydir}"/env.rc

use_wget() {
    local section="${1?Expected section name}"
    local file=${2?Expected file name}
    local source=${3?Expected source path}
    local target=${4?Expected target path}
    local -i error_code=0

    ### try-catch
    (
        ### this is a subshell block, so no changes to outside variables will persist
        set -o pipefail
        set -ex

        ### Warning, do not enclose '${_quiet:+-q}' into quotes, otherwise it'll cause the message
        ### 'http://: Invalid host name.' and the error code '1'.
        ### However, the download would proceed.
        wget --show-progress --progress=bar:force:noscroll ${_quiet:+-q} -O "${target}" "${source}"

    ) ; {
        
        ### catch - this block is entered only by errors in the try-block
        error_code=$?

        if [[ ${error_code} -ne 0 ]] ; then

            echo -e "${_mark} error '${error_code}' by downloading file '${file}' in section '${section}'" >&2

            echo -e "${_mark} renaming file '${file}' to '${file}_failed' in section '${section}'" >&2

            mv -f "${target}" "${target}_failed"
        fi
    }

    ### This procedure reports the 'wget' errors, but it does not fail on them.
    ### However, the created target file will be renamed with the suffix '_failed'.
    return 0
}

refresh_file() {
    local section="${1?Expected section name}"
    local file=${2?Expected file name}
    local source_url=${3?Expected source URL}
    local target=${4?Expected target path}

    local source="${_shared_cache_path}/${section}/${file}"

    if [[ ! -s "${target}" ]] ; then

        ### first try to copy the file from the shared cache
        if [[ -s "${source}" ]] ; then

            echo -e "${_mark} refreshing section '${section}' by copying shared file '${file}'\n"
            cp "${source}" "${target}"

        else
            ### otherwise download the file from the Internet

            echo -e "${_mark} refreshing section '${section}' by downloading file '${file}'\n"
            use_wget "${section}" "${file}" "${source_url}" "${target}"

            ### copy the downloaded file to the shared cache
            if [[ -n "${_shared_cache_path}" && -s "${target}" ]] ; then

                echo -e "${_mark} refreshing shared section '${section}' by copying downloaded file '${file}'\n"

                mkdir -p "${_shared_cache_path}/${section}"
                
                cp "${target}" "${source}"
            fi
        fi
    else
        echo -e "${_mark} hit file '${file}' in section '${section}'"
    fi
}

cache_tigervnc() {
    local section="tigervnc"
    local source_base_url="https://sourceforge.net/projects/tigervnc/files/stable"
    local target_path="${_cache}/${section}"
    local target=""
    local file=""

    mkdir -p "${target_path}"

    file="tigervnc-${TIGERVNC_VERSION}.${TIGERVNC_DISTRO}.tar.gz"
    source_url="${source_base_url}/${TIGERVNC_VERSION}/${file}"
    target="${target_path}/${file}"

    refresh_file "${section}" "${file}" "${source_url}" "${target}"
}

cache_novnc() {
    local section="novnc"
    local source_base_url="https://github.com/novnc/noVNC/archive/"
    local target_path="${_cache}/${section}"
    local target=""
    local file=""

    mkdir -p "${target_path}"

    file="v${NOVNC_VERSION}.tar.gz"
    source_url="${source_base_url}/${file}"
    target="${target_path}/${file}"

    refresh_file "${section}" "${file}" "${source_url}" "${target}"
}

cache_websockify() {
    local section="websockify"
    local source_base_url="https://github.com/novnc/websockify/archive"
    local target_path="${_cache}/${section}"
    local target=""
    local file=""

    mkdir -p "${target_path}"

    file="v${WEBSOCKIFY_VERSION}.tar.gz"
    source_url="${source_base_url}/${file}"
    target="${target_path}/${file}"

    refresh_file "${section}" "${file}" "${source_url}" "${target}"
}

### ==========
### cache_main
### ==========

### usage:
### PWD=<project root>
### ./docker/hooks/cache <branch> <blend> [-q|--quiet]

main() {

    if [[ "${FEATURES_VNC}" == "1" ]] ; then
        cache_tigervnc
    fi

    if [[ "${FEATURES_NOVNC}" == "1" ]] ; then

        cache_novnc
        cache_websockify
    fi

    echo
}

declare _quiet=""
declare _mark="\n==> G3-CACHE"
declare _cache="${_build_context}/.g3-cache"
declare _shared_cache_path="${SHARED_G3_CACHE_PATH}"

if [[ $# -gt 0 && "${1}" =~ -q|--quiet ]] ; then 

    _quiet="q"
    shift
fi

### main entry point
declare -i __exit_code=0
main $@

__exit_code=$?

echo -e "\n==> FINISHED  @$(date -u +'%Y-%m-%d_%H-%M-%S'): ${0} $@\n"

exit ${__exit_code}