#!/bin/sh

# This script installs the Nix package manager on your system by
# downloading a binary distribution and running its installer script
# (which in turn creates and populates /nix).

{ # Prevent execution if this script was only partially downloaded
oops() {
    echo "$0:" "$@" >&2
    exit 1
}

umask 0022

tmpDir="$(mktemp -d -t nix-binary-tarball-unpack.XXXXXXXXXX || \
          oops "Can't create temporary directory for downloading the Nix binary tarball")"
cleanup() {
    rm -rf "$tmpDir"
}
trap cleanup EXIT INT QUIT TERM

require_util() {
    command -v "$1" > /dev/null 2>&1 ||
        oops "you do not have '$1' installed, which I need to $2"
}

case "$(uname -s).$(uname -m)" in
    Linux.x86_64)
        hash=bbb319ff15a2445963064eb96fb08eb252a3991accc90c3db3379dd3668128be
        path=nwkcpknqva8hpxd4p1ardx0hysxhxbsq/nix-2.32.0-x86_64-linux.tar.xz
        system=x86_64-linux
        ;;
    Linux.i?86)
        hash=d7f00238e326907632542a2ea17f0476444a7d9797226e21d28245c4d24e042d
        path=nxnxq7qlszplfbmjnnpq5amrhiif6y4i/nix-2.32.0-i686-linux.tar.xz
        system=i686-linux
        ;;
    Linux.aarch64)
        hash=e0ffb3e30f995008206325aa028f8d062fc7466c7471ca957c0374ad7c39a133
        path=zj8dkvl3vyl56lbgyxnxlvwhz2lnm71g/nix-2.32.0-aarch64-linux.tar.xz
        system=aarch64-linux
        ;;
    Linux.armv6l)
        hash=8bbb580bd4e13f028cc7358c3030c3deb641d0862016304687eea5ca446b4163
        path=8dnjadnzr74bj7bw3qvs2pzyr0pdxcig/nix-2.32.0-armv6l-linux.tar.xz
        system=armv6l-linux
        ;;
    Linux.armv7l)
        hash=9af51e345e2a351bb1227c74e500de53c24f320d8a03a4f6d257089db4274a70
        path=zfr91x8hwi8ag83fgm5nl30a5kqn6054/nix-2.32.0-armv7l-linux.tar.xz
        system=armv7l-linux
        ;;
    Linux.riscv64)
        hash=427545cabb8b4cd61f681c0be2a376de686871ea95dcd1a82d085b0cb7133964
        path=sgk3fgdhi2m44cnmh81hv9i17nvbrihz/nix-2.32.0-riscv64-linux.tar.xz
        system=riscv64-linux
        ;;
    Darwin.x86_64)
        hash=aa1696e73e57a3f189874c3d1f3c4437bd20697a6bb26bc9987286f1faa8e09d
        path=xqj1p6vkmbppz5d1lanhimmixgxbzpqh/nix-2.32.0-x86_64-darwin.tar.xz
        system=x86_64-darwin
        ;;
    Darwin.arm64|Darwin.aarch64)
        hash=04b83f51286912ec14f3b3bf125353152b6a56a0fde974edd738a8418fde68de
        path=qazmgwx4jd3qzzjyghc3bx1ck40va6mq/nix-2.32.0-aarch64-darwin.tar.xz
        system=aarch64-darwin
        ;;
    *) oops "sorry, there is no binary distribution of Nix for your platform";;
esac

# Use this command-line option to fetch the tarballs using nar-serve or Cachix
if [ "${1:-}" = "--tarball-url-prefix" ]; then
    if [ -z "${2:-}" ]; then
        oops "missing argument for --tarball-url-prefix"
    fi
    url=${2}/${path}
    shift 2
else
    url=https://mirrors.tuna.tsinghua.edu.cn/nix//nix-2.32.0/nix-2.32.0-$system.tar.xz
fi

tarball=$tmpDir/nix-2.32.0-$system.tar.xz

require_util tar "unpack the binary tarball"
if [ "$(uname -s)" != "Darwin" ]; then
    require_util xz "unpack the binary tarball"
fi

if command -v curl > /dev/null 2>&1; then
    fetch() { curl --fail -L "$1" -o "$2"; }
elif command -v wget > /dev/null 2>&1; then
    fetch() { wget "$1" -O "$2"; }
else
    oops "you don't have wget or curl installed, which I need to download the binary tarball"
fi

echo "downloading Nix 2.32.0 binary tarball for $system from '$url' to '$tmpDir'..."
fetch "$url" "$tarball" || oops "failed to download '$url'"

if command -v sha256sum > /dev/null 2>&1; then
    hash2="$(sha256sum -b "$tarball" | cut -c1-64)"
elif command -v shasum > /dev/null 2>&1; then
    hash2="$(shasum -a 256 -b "$tarball" | cut -c1-64)"
elif command -v openssl > /dev/null 2>&1; then
    hash2="$(openssl dgst -r -sha256 "$tarball" | cut -c1-64)"
else
    oops "cannot verify the SHA-256 hash of '$url'; you need one of 'shasum', 'sha256sum', or 'openssl'"
fi

if [ "$hash" != "$hash2" ]; then
    oops "SHA-256 hash mismatch in '$url'; expected $hash, got $hash2"
fi

unpack=$tmpDir/unpack
mkdir -p "$unpack"
tar -xJf "$tarball" -C "$unpack" || oops "failed to unpack '$url'"

script=$(echo "$unpack"/*/install)

[ -e "$script" ] || oops "installation script is missing from the binary tarball!"
export INVOKED_FROM_INSTALL_IN=1
"$script" "$@"

} # End of wrapping