#!/bin/bash
# LinuxGSM core_dl.sh function
# Author: Daniel Gibbs
# Contributor: UltimateByte
# Website: https://linuxgsm.com
# Description: Deals with all downloads for LinuxGSM.

# remote_fileurl: The URL of the file: http://example.com/dl/File.tar.bz2
# local_filedir: location the file is to be saved: /home/server/lgsm/tmp
# local_filename: name of file (this can be different from the url name): file.tar.bz2
# chmodx: Optional, set to "chmodx" to make file executable using chmod +x
# run: Optional, set run to execute the file after download
# forcedl: Optional, force re-download of file even if exists
# md5: Optional, set an md5 sum and will compare it against the file.
#
# Downloads can be defined in code like so:
# fn_fetch_file "${remote_fileurl}" "${local_filedir}" "${local_filename}" "${chmodx}" "${run}" "${forcedl}" "${md5}"
# fn_fetch_file "http://example.com/file.tar.bz2" "/some/dir" "file.tar.bz2" "chmodx" "run" "forcedl" "10cd7353aa9d758a075c600a6dd193fd"

local commandname="DOWNLOAD"
local commandaction="Download"
local function_selfname="$(basename "$(readlink -f "${BASH_SOURCE[0]}")")"

# Emptys contents of the LinuxGSM tmpdir.
fn_clear_tmp(){
	echo -en "clearing LinuxGSM tmp directory..."
	if [ -d "${tmpdir}" ]; then
		rm -rf "${tmpdir:?}/"*
		local exitcode=$?
		if [ ${exitcode} -eq 0 ]; then
			fn_print_ok_eol_nl
			fn_script_log_pass "clearing LinuxGSM tmp directory"
		else
			fn_print_error_eol_nl
			fn_script_log_error "clearing LinuxGSM tmp directory"
		fi
	fi	
}

fn_dl_md5(){
	# Runs MD5 Check if available.
	if [ "${md5}" != "0" ]&&[ "${md5}" != "nomd5" ]; then
		echo -en "verifying ${local_filename} with MD5..."
		fn_sleep_time
		local md5sumcmd=$(md5sum "${local_filedir}/${local_filename}"|awk '{print $1;}')
		if [ "${md5sumcmd}" != "${md5}" ]; then
			fn_print_fail_eol_nl
			echo "${local_filename} returned MD5 checksum: ${md5sumcmd}"
			echo "expected MD5 checksum: ${md5}"
			fn_script_log_fatal "Verifying ${local_filename} with MD5"
			fn_script_log_info "${local_filename} returned MD5 checksum: ${md5sumcmd}"
			fn_script_log_info "Expected MD5 checksum: ${md5}"
			core_exit.sh
		else
			fn_print_ok_eol_nl
			fn_script_log_pass "Verifying ${local_filename} with MD5"
			fn_script_log_info "${local_filename} returned MD5 checksum: ${md5sumcmd}"
			fn_script_log_info "Expected MD5 checksum: ${md5}"
		fi
	fi
}

# Extracts bzip2, gzip or zip files.
# Extracts can be defined in code like so:
# fn_dl_extract "${local_filedir}" "${local_filename}" "${extractdir}"
# fn_dl_extract "/home/gameserver/lgsm/tmp" "file.tar.bz2" "/home/gamserver/serverfiles"
fn_dl_extract(){
	local_filedir="${1}"
	local_filename="${2}"
	extractdir="${3}"
	# Extracts archives.
	echo -en "extracting ${local_filename}..."
	mime=$(file -b --mime-type "${local_filedir}/${local_filename}")
	if [ ! -d "${extractdir}" ]; then
		mkdir "${extractdir}"
	fi
	if [ "${mime}" == "application/gzip" ]||[ "${mime}" == "application/x-gzip" ]; then
		extractcmd=$(tar -zxf "${local_filedir}/${local_filename}" -C "${extractdir}")
	elif [ "${mime}" == "application/x-bzip2" ]; then
		tarcmd=$(tar -jxf "${local_filedir}/${local_filename}" -C "${extractdir}")
	elif [ "${mime}" == "application/x-xz" ]; then
		tarcmd=$(tar -xf "${local_filedir}/${local_filename}" -C "${extractdir}")
	elif [ "${mime}" == "application/zip" ]; then
		extractcmd=$(unzip -d "${extractdir}" "${local_filedir}/${local_filename}")
	fi
	local exitcode=$?
	if [ ${exitcode} -ne 0 ]; then
		fn_print_fail_eol_nl
		fn_script_log_fatal "Extracting download"
		if [ -f "${lgsmlog}" ]; then
			echo "${extractcmd}" >> "${lgsmlog}"
		fi
		echo "${extractcmd}"
		core_exit.sh
	else
		fn_print_ok_eol_nl
		fn_script_log_pass "Extracting download"
	fi
}

# Trap to remove file download if canceled before completed.
fn_fetch_trap(){
	echo ""
	echo -en "downloading ${local_filename}..."
	fn_print_canceled_eol_nl
	fn_script_log_info "Downloading ${local_filename}...CANCELED"
	fn_sleep_time
	rm -f "${local_filedir}/${local_filename}"
	echo -en "downloading ${local_filename}..."
	fn_print_removed_eol_nl
	fn_script_log_info "Downloading ${local_filename}...REMOVED"
	core_exit.sh
}

fn_fetch_file(){
	remote_fileurl="${1}"
	local_filedir="${2}"
	local_filename="${3}"
	chmodx="${4:-0}"
	run="${5:-0}"
	forcedl="${6:-0}"
	md5="${7:-0}"

	# Download file if missing or download forced.
	if [ ! -f "${local_filedir}/${local_filename}" ]||[ "${forcedl}" == "forcedl" ]; then
		if [ ! -d "${local_filedir}" ]; then
			mkdir -p "${local_filedir}"
		fi
		# Trap will remove part downloaded files if canceled.
		trap fn_fetch_trap INT
		# Larger files show a progress bar.
		if [ "${local_filename##*.}" == "bz2" ]||[ "${local_filename##*.}" == "gz" ]||[ "${local_filename##*.}" == "zip" ]||[ "${local_filename##*.}" == "jar" ]||[ "${local_filename##*.}" == "xz" ]; then
			echo -en "downloading ${local_filename}..."
			fn_sleep_time
			echo -en "\033[1K"
			curlcmd=$(${curlpath} --progress-bar --fail -L -o "${local_filedir}/${local_filename}" "${remote_fileurl}")
			echo -en "downloading ${local_filename}..."
		else
			echo -en "    fetching ${local_filename}...\c"
			curlcmd=$(${curlpath} -s --fail -L -o "${local_filedir}/${local_filename}" "${remote_fileurl}" 2>&1)
		fi
		local exitcode=$?
		if [ ${exitcode} -ne 0 ]; then
			fn_print_fail_eol_nl
			if [ -f "${lgsmlog}" ]; then
				fn_script_log_fatal "Downloading ${local_filename}"
				echo -e "${remote_fileurl}" >> "${lgsmlog}"
				echo "${curlcmd}" >> "${lgsmlog}"
			fi
			echo -e "${remote_fileurl}"
			echo "${curlcmd}"
			core_exit.sh
		else
			fn_print_ok_eol_nl
			if [ -f "${lgsmlog}" ]; then
				fn_script_log_pass "Downloading ${local_filename}"
			fi
		fi
		# Remove trap.
		trap - INT
		# Make file executable if chmodx is set.
		if [ "${chmodx}" == "chmodx" ]; then
			chmod +x "${local_filedir}/${local_filename}"
		fi
	fi

	if [ -f "${local_filedir}/${local_filename}" ]; then
		fn_dl_md5
		# Execute file if run is set.
		if [ "${run}" == "run" ]; then
			source "${local_filedir}/${local_filename}"
		fi
	fi
}

# GitHub file download functions.
# Used to simplify downloading specific files from GitHub.

# github_file_url_dir: the directory of the file in the GitHub: lgsm/functions
# github_file_url_name: the filename of the file to download from GitHub: core_messages.sh
# githuburl: the full GitHub url

# remote_fileurl: The URL of the file: http://example.com/dl/File.tar.bz2
# local_filedir: location the file is to be saved: /home/server/lgsm/tmp
# local_filename: name of file (this can be different from the url name): file.tar.bz2
# chmodx: Optional, set to "chmodx" to make file executable using chmod +x
# run: Optional, set run to execute the file after download
# forcedl: Optional, force re-download of file even if exists
# md5: Optional, set an md5 sum and will compare it against the file.

# Fetches any files from the GitHub repo.
fn_fetch_file_github(){
	github_file_url_dir="${1}"
	github_file_url_name="${2}"
	githuburl="https://raw.githubusercontent.com/${githubuser}/${githubrepo}/${githubbranch}/${github_file_url_dir}/${github_file_url_name}"

	remote_fileurl="${githuburl}"
	local_filedir="${3}"
	local_filename="${github_file_url_name}"
	chmodx="${4:-0}"
	run="${5:-0}"
	forcedl="${6:-0}"
	md5="${7:-0}"
	# Passes vars to the file download function.
	fn_fetch_file "${remote_fileurl}" "${local_filedir}" "${local_filename}" "${chmodx}" "${run}" "${forcedl}" "${md5}"
}

fn_fetch_config(){
	github_file_url_dir="${1}"
	github_file_url_name="${2}"
	githuburl="https://raw.githubusercontent.com/${githubuser}/${githubrepo}/${githubbranch}/${github_file_url_dir}/${github_file_url_name}"

	remote_fileurl="${githuburl}"
	local_filedir="${3}"
	local_filename="${4}"
	chmodx="nochmodx"
	run="norun"
	forcedl="noforce"
	md5="nomd5"
	# Passes vars to the file download function.
	fn_fetch_file "${remote_fileurl}" "${local_filedir}" "${local_filename}" "${chmodx}" "${run}" "${forcedl}" "${md5}"
}

# Fetches functions.
fn_fetch_function(){
	github_file_url_dir="lgsm/functions"
	github_file_url_name="${functionfile}"
	githuburl="https://raw.githubusercontent.com/${githubuser}/${githubrepo}/${githubbranch}/${github_file_url_dir}/${github_file_url_name}"

	remote_fileurl="${githuburl}"
	local_filedir="${functionsdir}"
	local_filename="${github_file_url_name}"
	chmodx="chmodx"
	run="run"
	forcedl="noforce"
	md5="nomd5"
	# Passes vars to the file download function.
	fn_fetch_file "${remote_fileurl}" "${local_filedir}" "${local_filename}" "${chmodx}" "${run}" "${forcedl}" "${md5}"
}

fn_update_function(){
	exitbypass=1
	github_file_url_dir="lgsm/functions"
	github_file_url_name="${functionfile}"
	githuburl="https://raw.githubusercontent.com/${githubuser}/${githubrepo}/${githubbranch}/${github_file_url_dir}/${github_file_url_name}"

	remote_fileurl="${githuburl}"
	local_filedir="${functionsdir}"
	local_filename="${github_file_url_name}"
	chmodx="chmodx"
	run="norun"
	forcedl="noforce"
	md5="nomd5"
	fn_fetch_file "${remote_fileurl}" "${local_filedir}" "${local_filename}" "${chmodx}" "${run}" "${forcedl}" "${md5}"
}

# Defines curl path.
curlpath=$(command -v curl 2>/dev/null)

if [ "$(basename "${curlpath}")" != "curl" ]; then
	echo "[ FAIL ] Curl is not installed"
	exit 1
fi