#!/usr/bin/env bash

APP=bat
VERSION=${VERSION:-v0.17.1}
DATA_DIR="${XDG_DATA_HOME}/apps/releases"
DEST_DIR="${DATA_DIR}/${APP}/${VERSION}"

OS=
ARCH=
case $(uname -s) in
    Linux*)                 OS=unknown-linux-gnu;;
    Darwin*)                OS=apple-darwin;;
    CYGWIN_NT*|Windows_NT*) OS=pc-windows-msvc;;
    *) >&2 echo "unsupported os"; return;
esac

case $(uname -m) in
    amd64*|x86_64*)     ARCH=x86_64;;
    i686*|i386*)        ARCH=i686;;
    arm|armv7*|armv6*)  ARCH=arm;;
    aarch64*|armv8*)    ARCH=arm64;;
    *) >&2 echo "unsupported architecture: $(uname -m)"; exit 1;;
esac

function bail () {
    echo "unexpected error $1"
    exit 1
}

function do_link () {
    local dir="$1"
    local link="$2"
    if [[ ! -d "${dir}" ]] ; then
        return
    fi
    if [[ -L "${dir}/$(basename "${link}")" ]] ; then
        return
    fi
    cd "${dir}" || bail "failed to change directory: ${dir}"
    ln --symbolic "${link}" "$(basename "${link}")"
}

URL="https://github.com/sharkdp/bat/releases/download/${VERSION}/bat-${VERSION}-${ARCH}-${OS}.tar.gz"
TMP_DIR=
if [[ ! -d "${DEST_DIR}" ]] ; then
    set -x
    TMP_DIR=$(mktemp --directory)
    TAR_GZ="${TMP_DIR}/release.tar.gz"
    echo "start download: ${URL}"
    curl --location --silent --output "${TAR_GZ}" "${URL}"
    echo "stop download: ${URL}"
    mkdir -p "${DEST_DIR}"
    tar xzf "${TAR_GZ}" --strip-components 1 --directory "${DEST_DIR}"
    rm -rf "${TMP_DIR}"
fi
unset TMP_DIR

cd "${DATA_DIR}/${APP}" || bail "directory change failed: ${DATA_DIR}/${APP}"
[[ -s current ]] && unlink current
ln -s "${VERSION}" current

ZSH_CONFIG_D="${XDG_CONFIG_HOME}/zsh/zshrc.d"
FISH_CONFIG_D="${XDG_CONFIG_HOME}/fish/functions"
MAN_DIR="${XDG_DATA_HOME}/man/man1"
[[ -d ${MAN_DIR} ]] || mkdir -p "${MAN_DIR}"

do_link "${XDG_BIN_HOME}" "${DATA_DIR}/${APP}/current/bat"
do_link "${ZSH_CONFIG_D}" "${DATA_DIR}/${APP}/current/autocomplete/bat.zsh"
do_link "${FISH_CONFIG_D}" "${DATA_DIR}/${APP}/current/autocomplete/bat.fish"
do_link "${MAN_DIR}" "${DATA_DIR}/${APP}/current/bat.1"