#!/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=99362375dc92e24fdea3c7524b649b9b62eb7e6ce2d71a198c2c8959f299da43
        path=777m1q62klj19fl9vj73z0j386ycrfh5/nix-2.33.2-x86_64-linux.tar.xz
        system=x86_64-linux
        ;;
    Linux.i?86)
        hash=b16d2f60d02a35c2c5aea16ea546012e51c0a2398e50d8483fb0adea2877a385
        path=vd2r6wk7pam1g203g49vv4343140aazq/nix-2.33.2-i686-linux.tar.xz
        system=i686-linux
        ;;
    Linux.aarch64)
        hash=a08b201270dd5efef18c9c04eb807f6dce91b9e0293d7f255c10539b8d840bc5
        path=hfqzr1anp7mazagq9sjsjj4f32ma0a9f/nix-2.33.2-aarch64-linux.tar.xz
        system=aarch64-linux
        ;;
    Linux.armv6l)
        hash=205c8ae9114ec5c36643842c35e5c0b039319a9cce0d0dfeb1c18e76d36469f2
        path=vn1wdk8wmgjfhk69wp8q26g4r65k3isi/nix-2.33.2-armv6l-linux.tar.xz
        system=armv6l-linux
        ;;
    Linux.armv7l)
        hash=1315be4eaa4a0fa0513c1ce2e530a1acdc64b9b7aa3fcd30da6abb2021b02f5c
        path=yq10qd5skwjm7aabi7pwcfbx01qgxyzc/nix-2.33.2-armv7l-linux.tar.xz
        system=armv7l-linux
        ;;
    Linux.riscv64)
        hash=9b0d65434770864802b113f5b92a745207251ae9a3670fb9a5bfa068e3a5efd5
        path=7jn74rg8xjysrkb6929fkmm0v6875lyv/nix-2.33.2-riscv64-linux.tar.xz
        system=riscv64-linux
        ;;
    Darwin.x86_64)
        hash=962f8ef9e3fa2e4230e79e6e4acff024e66a3ca5d08d5e93c89ba649bed6878f
        path=mnqck57v3va8r751jvdrcslyqkx501f6/nix-2.33.2-x86_64-darwin.tar.xz
        system=x86_64-darwin
        ;;
    Darwin.arm64|Darwin.aarch64)
        hash=04b205612978e5304e5a3af020a75946580706103cb96446dc8e976f144f0c84
        path=azjdf8jid7l63bvz6jblwggk70n9z05s/nix-2.33.2-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-2.33.2/nix-2.33.2-$system.tar.xz
fi

tarball=$tmpDir/nix-2.33.2-$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 2.33.2 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