#!/usr/bin/env bash

SCRIPT_NAME="$(basename "${0}")"
FALLOUT4_EXECUTABLE="Fallout4.exe"
WINE_REGISTRY_KEY="HKEY_CURRENT_USER\\Software\\Wine"
FALLOUT4_APPDEFAULTS_REGISTRY_KEY="HKEY_CURRENT_USER\\Software\\Wine\\AppDefaults\\${FALLOUT4_EXECUTABLE}"
FALLOUT4_INSTALL_REGISTRY_KEY='HKEY_LOCAL_MACHINE\Software\Bethesda Softworks\Fallout4'
USER_SHELL_FOLDERS_REGISTRY_KEY='HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Shell Folders'


function die() {
    printf "%s : %s() : %s\\n" "${SCRIPT_NAME}" "${FUNCNAME[1]}" "${1}" >&2
    exit 1
}

# get_registry_value()
#   Returns "data" from a specified Registry key and value, where "value"="data".
#   Note: the Wine reg query result will use \r\n CR linefeeds - strip these!
function get_registry_value() {
    local registry_key="${1}" registry_value="${2}"
    declare -n data="${3}"

    data="$(wine reg query "${registry_key}" /v "${registry_value}" 2>/dev/null \
        | awk -F 'REG_[A-Z]*' \
            -vregistry_value="${registry_value}" \
        '{
            for (i=1;i<=NF;++i)
                gsub("(^[[:blank:]]*|[[:blank:]]*$)","",$i)
            if ($1 == registry_value)
                print $2
        }' 2>/dev/null \
        | sed 's/\r//g'
    )"
    [[ -z "${data}" ]] && die "Registry key data lookup [${registry_key}] \"${registry_value}\"=... failed"
}

# add_registry_value()
#   Adds a Wine Registry key or a key plus "value"="data".
function add_registry_value() {
	local registry_key="${1}" registry_value="${2}" data="${3}" type="${4}"

	if [[ -z "${registry_value}" ]]; then
		wine reg add "${registry_key}" /f 2>/dev/null \
			|| die "Failed to add Registry key [${registry_key}]"
	else
		wine reg add "${registry_key}" /v "${registry_value}" /t "${type}" /d "${data}" /f 2>/dev/null \
			|| die "Failed to add Registry key+value: [${registry_key}] \"${registry_value}\"=\"${data}\" (${type})"
	fi
}

# delete_registry_value()
#   Deletes a Wine Registry key or key plus value pair.
function delete_registry_value() {
	local registry_key="${1}" registry_value="${2}"

	if [[ -z "${registry_value}" ]]; then
		wine reg delete "${registry_key}" /va /f &>/dev/null
	else
		wine reg delete "${registry_key}" /v "${registry_value}" /f &>/dev/null
	fi
}

# convert_windows_to_unix_path()
#   Convert a Windows path to a canonical Unix path - follows all symbolic links.
#   Note: winepath outputs \r\n CR linefeeds - so we must strip these!
function convert_windows_to_unix_path() {
	local windows_path="${1}" unix_path
	declare -n canonical_unix_path="${2}"

	unix_path="$(winepath -u ''"${windows_path}"'' 2>/dev/null | sed 's/\r//g')"
	canonical_unix_path="$(readlink -f "${unix_path}")"
	if [[ ! -d "${canonical_unix_path}" ]]; then
		die "Unable to convert Windows directory: \"${windows_path}\"; to a Unix directory."
	fi
}

# find_file()
#   Finds a specified file, using a specified base directory+relative path offset.
#   Note: must use a case-insensitive search!
function find_file() {
	local search_path="${1}" relative_path="${2}" depth relative_path_regex
	declare -n target="${3}"
	[[ -d "${search_path}" ]] || die "File search directory does not exist \"${search_path}\""
	depth="$(echo "${relative_path}" | awk -F'/' '{ print NF }')"
	relative_path_regex=".*$(echo "${relative_path}" | sed 's/[-.()\/]/\\&/g' 2>/dev/null)"
# Without this last grep you will end up finding multiple directories
	target="$(find "${search_path}" -mindepth "$((depth-1))" -maxdepth "$((depth))" -iregex "${relative_path_regex}" 2>/dev/null | grep "${2}")"
	[[ -f "${target}" ]] || die "File search failed: \"${search_path}${relative_path}\""
}

# ini_file_overwrite_value()
#   Add/Overwrite name=value pair in a specified .ini file section.
#   Note: Windows .ini files will use \r\n CR linefeeds - don't break this!
function ini_file_overwrite_value() {
	local ini_file="${1}" name="${2}" value="${3}" section="${4}"
	[[ -f "${ini_file}" ]] || die ".ini file path not valid: \"${ini_file}\""

	# shellcheck disable=SC1004
	sed -i -e '\|^'"${name}"'=|d' -e '\|^\['"${section}"'\]|a\
'"${name}=${value}\\r" "${ini_file}" 2>/dev/null \
		|| die "sed operation failed on: \"${ini_file}\""
}

# I don't like it when scripts are messy and dirty like they lack a main function.
# Makes it so much harder to read them.
function main {
	[[ -z "${WINEPREFIX}" ]] && die "WINEPREFIX env variable not set"
	[[ -d "${WINEPREFIX}" ]] || die "WINEPREFIX env variable is set to an invalid path: \"${WINEPREFIX}\""
	((EUID==0)) && die "Do not run this script as the root user!"

# Get Wine user 'My Documents' folder from Wine Registry.
	get_registry_value "${USER_SHELL_FOLDERS_REGISTRY_KEY}" \
		'Personal' "WINDOWS_USER_DOCUMENTS_PATH"
	convert_windows_to_unix_path "${WINDOWS_USER_DOCUMENTS_PATH}" "UNIX_USER_DOCUMENTS_PATH"

# Get install directory of Fallout 4 from Wine Registry.
	get_registry_value "${FALLOUT4_INSTALL_REGISTRY_KEY}" \
		'installed path' "WINDOWS_FALLOUT4_INSTALL_PATH"
	convert_windows_to_unix_path "${WINDOWS_FALLOUT4_INSTALL_PATH}" "UNIX_FALLOUT4_INSTALL_PATH"

# Find 2 main Fallout 4 configuration files.
	find_file "${UNIX_USER_DOCUMENTS_PATH}" '/My Games/Fallout4/Fallout4.ini' "USER_FALLOUT4_INI_FILE"
	find_file "${UNIX_FALLOUT4_INSTALL_PATH}" 'Fallout4_Default.ini' "GAME_FALLOUT4DEFAULT_INI_FILE"

# Set bBackgroundMouse=1 : Switches between the game controlling the mouse position (0) or the operating system (1).
	ini_file_overwrite_value "${USER_FALLOUT4_INI_FILE}" "bBackgroundMouse" "1" "Controls"
	ini_file_overwrite_value "${GAME_FALLOUT4DEFAULT_INI_FILE}" "bBackgroundMouse" "1" "Controls"

# GrabFullscreen=Y
	add_registry_value "${WINE_REGISTRY_KEY}\\X11 Driver" 'GrabFullscreen' 'Y' 'REG_SZ'

# Version=win7
	add_registry_value "${FALLOUT4_APPDEFAULTS_REGISTRY_KEY}" 'Version' 'win7' 'REG_SZ'

# Setup winetricks xact
	winetricks -q --force xact &>/dev/null || die "winetricks xact failed"

# Move xact audio Dll Overrides to Fallout 4 AppDefaults. So this set of DLL Overrides
# doesn't affect other games/applications in the same Wineprefix.
	for dll in "xaudio2_0" "xaudio2_1" "xaudio2_2" "xaudio2_3" "xaudio2_4" "xaudio2_5" "xaudio2_6" "xaudio2_7" "x3daudio1_0" "x3daudio1_1" "x3daudio1_2" "x3daudio1_3" "x3daudio1_4" "x3daudio1_5" "x3daudio1_6" "x3daudio1_7"; do
		delete_registry_value "${WINE_REGISTRY_KEY}\\DllOverrides" "*${dll}"
		delete_registry_value "${WINE_REGISTRY_KEY}\\DllOverrides" "*${dll}"
		delete_registry_value "${FALLOUT4_APPDEFAULTS_REGISTRY_KEY}\\DllOverrides" "*${dll}"
		add_registry_value "${FALLOUT4_APPDEFAULTS_REGISTRY_KEY}\\DllOverrides" "${dll}" 'native,builtin' 'REG_SZ'
	done

# Delete all xact DLL Overrides we don't required (2D audio as well?)
	for dll in "xapofx1_1" "xapofx1_2" "xapofx1_3" "xapofx1_4" "xapofx1_5"; do
		delete_registry_value "${WINE_REGISTRY_KEY}\\DllOverrides" "${dll}"
		delete_registry_value "${WINE_REGISTRY_KEY}\\DllOverrides" "*${dll}"
	done
}

main $@