#!/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=1906ee6528901761a3cafa73521a12f3e4d7203bd550af237ab8326d9aa20b0b
        path=znsa42x060fp46nfx5d0dfqkj3nykynb/nix-2.32.8-x86_64-linux.tar.xz
        system=x86_64-linux
        ;;
    Linux.i?86)
        hash=264aeb62800cf933d643bbf0bf9824ac42361b7bb0c24a923ec82293dc3cdd57
        path=k43mmshj31yccmrpr3g07n215byhyl25/nix-2.32.8-i686-linux.tar.xz
        system=i686-linux
        ;;
    Linux.aarch64)
        hash=8b32f26c85771e3582236fddb47da640d454258ac7fe0129b5483b1bafb1100b
        path=syjabac84dcbzg896rgrys2c6y5f6syh/nix-2.32.8-aarch64-linux.tar.xz
        system=aarch64-linux
        ;;
    Linux.armv6l)
        hash=b0ea2380a2feb88e5fa356b9e0a3adaf74c61677b73e47683d46a3b8564a7d11
        path=li0iwij3qj8wlbjm6lsar60db7zbmjsl/nix-2.32.8-armv6l-linux.tar.xz
        system=armv6l-linux
        ;;
    Linux.armv7l)
        hash=970460aba08a8b5a3fdb6d24aa3bf73b189d09baf723ed8b4615cd3fa4acc4d3
        path=n6sc4zz7bafkplhi73ycgyvnhabydf1r/nix-2.32.8-armv7l-linux.tar.xz
        system=armv7l-linux
        ;;
    Linux.riscv64)
        hash=c50bb77d35d0c8048fc64024dab7324e2e61ee9926e236c148302f24c0750a83
        path=xns08p4kkcxmvfsas0s85qpia8s8c6xs/nix-2.32.8-riscv64-linux.tar.xz
        system=riscv64-linux
        ;;
    Darwin.x86_64)
        hash=40d63861343a4d7d43dfac1f85753792d72811c13cf9692ca0343e153eee506d
        path=qnjz5g7vw4ky5r3kk32l9rlh7kay77jl/nix-2.32.8-x86_64-darwin.tar.xz
        system=x86_64-darwin
        ;;
    Darwin.arm64|Darwin.aarch64)
        hash=76b0abc1b76508df2b95b62b981af5069fae3dff4d31d8e10ce0fe90374e8ab1
        path=rf2q1sk1058bmagwyy2rijhz0lbm2bk3/nix-2.32.8-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://mirror.nju.edu.cn/nix/nix-2.32.8/nix-2.32.8-$system.tar.xz
fi

tarball=$tmpDir/nix-2.32.8-$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 2.32.8 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