#!/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=d9d66e734641c3b9acf22ad0b52b165c0e887d10e4afce54c490228d9de406a4
        path=l1g8x8mvcfh14hcl7c7pa41iq6xfp997/nix-2.32.3-x86_64-linux.tar.xz
        system=x86_64-linux
        ;;
    Linux.i?86)
        hash=c7a943fcb6ca23e4b76d7aaf43947f637755bc2c8cb8408c480efd8b8a80b58e
        path=bsdsfskcd2dskmbydjwdk8l5w4gnqmr3/nix-2.32.3-i686-linux.tar.xz
        system=i686-linux
        ;;
    Linux.aarch64)
        hash=9f4e5ea6b5259e651d727646172f53c726ebf9b0f708dfb68ed2023698dd00a3
        path=8irwqqscv3hgymyfysy0kl45hqvs1mhx/nix-2.32.3-aarch64-linux.tar.xz
        system=aarch64-linux
        ;;
    Linux.armv6l)
        hash=2180b7b93118a4071793c26815ddb036a681067c51233b143d42103713a661fd
        path=j3hm7yjgbjjcnls5zva8lgf0qf33kd04/nix-2.32.3-armv6l-linux.tar.xz
        system=armv6l-linux
        ;;
    Linux.armv7l)
        hash=0be6653cc4961d1bbf06f859bf206899c019c1deab889fbece9a58c0861ceeb4
        path=vpkc4jwnx0xv36nm2lla4dlqrv44j1fq/nix-2.32.3-armv7l-linux.tar.xz
        system=armv7l-linux
        ;;
    Linux.riscv64)
        hash=2607cee5794bbb291c387ce4286ffa6faa84aaf1f8e2c2b9fa0dab8870212fa2
        path=wa7qj3g9lbdih6m8axgnk25w0acplbag/nix-2.32.3-riscv64-linux.tar.xz
        system=riscv64-linux
        ;;
    Darwin.x86_64)
        hash=efd314d1b155a5c95836af32033be39d6437570c2f671a55047d48634d8a20ac
        path=agwivwym0isiyfmhk9ssic0lr8ki1whg/nix-2.32.3-x86_64-darwin.tar.xz
        system=x86_64-darwin
        ;;
    Darwin.arm64|Darwin.aarch64)
        hash=e7080d2dd3c3a278736517e21f50ee99c93b8773b1ded4346b7ba6939a932c83
        path=7i6h311wr8yyiizmyrn51xdbr5wgmwsb/nix-2.32.3-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-2.32.3/nix-2.32.3-$system.tar.xz
fi

tarball=$tmpDir/nix-2.32.3-$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 2.32.3 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