#!/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=e8912e087582b3799e0e5a6b06f9d63386c54821f77ad4de3b9b748736ad364e
        path=5m7cq490y46wgl699hy6ds4z1mbrjka6/nix-2.34.9-x86_64-linux.tar.xz
        system=x86_64-linux
        ;;
    Linux.i?86)
        hash=f6280f8af31c5c44effc335e304a7315e82af2bd3396bafd8ab81340ecca6b69
        path=mqnlicjxfkz1zps6zp8gmn0ylmykr379/nix-2.34.9-i686-linux.tar.xz
        system=i686-linux
        ;;
    Linux.aarch64)
        hash=f0bb2518db6c9db3f925be3edb76f6e0da17cb72fba329493f510ca08e5111a7
        path=ida963gqmxgkcdjwnlqfdip239mjii9y/nix-2.34.9-aarch64-linux.tar.xz
        system=aarch64-linux
        ;;
    Linux.armv6l)
        hash=339496c636668cdd74f528de6d6d32994cba5ddb51651799b31a4cdd04ca5689
        path=dpvf9zfvw3v653irwwwiwvjsg0vbzbgv/nix-2.34.9-armv6l-linux.tar.xz
        system=armv6l-linux
        ;;
    Linux.armv7l)
        hash=82eac1ecee592f2c260d9841662264b8bb97b198d23ceed5134bf9bc5c2e9d60
        path=mnpy62ddxhrdv5j4dd5qi6zws5y97kjm/nix-2.34.9-armv7l-linux.tar.xz
        system=armv7l-linux
        ;;
    Linux.riscv64)
        hash=420314176149c7df7630181bfc7a73a61349f6b8129bcd2599fd511e8b5876f6
        path=rj56bf3slf4z1qr6c6fdh1vcjs46168q/nix-2.34.9-riscv64-linux.tar.xz
        system=riscv64-linux
        ;;
    Darwin.x86_64)
        hash=7bd63afd5c57231e948a0fb4708ff4c60ae1a7bc7c7c31154462a05d498d6209
        path=bjn4173j6sphvxpm9qg9nsfswaiwg4jn/nix-2.34.9-x86_64-darwin.tar.xz
        system=x86_64-darwin
        ;;
    Darwin.arm64|Darwin.aarch64)
        hash=2720033f9854c666988f65cb2a9a2f73bb5c34f71eea6e47f4826473583ac703
        path=k0k6kvwnsg0qpv54wdbxma60bnl1xjai/nix-2.34.9-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-2.34.9/nix-2.34.9-$system.tar.xz
fi

tarball=$tmpDir/nix-2.34.9-$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 2.34.9 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