#!/usr/bin/env nix-shell
#!nix-shell -i zsh -p zsh -p nix

set -e
set -u
set -o pipefail

source $DOTFILES_PATH/bin/lib/util.zsh

cmdname=$(basename $0)
usage() {
  print "Usage: $cmdname <via_host> <hostname>" >&2
}

if [[ $# -ge 1 ]]
then
  if [[ "$1" = "--help" || "$1" = "-h" ]]
  then
      usage
      exit 0
  fi
fi

if [ $# -ne 2 ]
then
  print "Invalid number of arguments." >&2
  usage
  exit 2
fi

via_host="$1"
hostname="$2"


nixos_system_file=$MACHINES_PATH/nixos.nix

# This script cannot run without the nixos configuration entry point
if [[ ! -f "$nixos_system_file" ]]
then
  print -P "%B%F{red}Error: %F{orange}nixos.nix%F{red} not found%b%f" >&2
  exit 2
fi


local_temp_dir=$(mktemp --tmpdir --directory install-via.XXXXXXXXXX)
trap "rm -rf $local_temp_dir" EXIT INT HUP TERM

# Pre-build installation helper
nix build --file $DOTFILES_PATH/bin/lib/format.nix --argstr hostname "$hostname" --arg template "(import $MACHINES_PATH).machineTemplates.$hostname" --out-link "$local_temp_dir/format_$hostname"

if ! ssh -o VisualHostKey=yes root@$via_host true
then
  print "Cannot connect to host '$via_host'" >&2
  exit 1
fi

if ! nix ping-store --store ssh://root@$via_host
then
  print "Cannot connect to nix store on '$via_host'" >&2
  exit 1
fi

local_config_file=$local_temp_dir/config

# Prepare config
#luks_key=$(pass hosts/$hostname/luks)
luks_key=""
> $local_config_file <<EOF
{
  "blockDevice": null,
  "luksKey": "$luks_key"
}
EOF
luks_key=""

nix copy --file $DOTFILES_PATH/bin/lib/format.nix --argstr hostname "$hostname" --arg template "(import $MACHINES_PATH).machineTemplates.$hostname" --to ssh://root@$via_host

remote_temp_dir=$(ssh root@$via_host mktemp --tmpdir --directory install-via.XXXXXXXXXX)
# copy install-helper and config
scp -r $local_temp_dir/* root@$via_host:$remote_temp_dir/
scp $DOTFILES_PATH/bin/message root@$via_host:$remote_temp_dir/

ssh root@$via_host "$remote_temp_dir/message" &

# -t: Force pseudo-terminal allocation
ssh -t root@$via_host "$remote_temp_dir/format_$hostname/bin/format_$hostname" "$remote_temp_dir/config" "$remote_temp_dir/output.json"
scp "root@$via_host:$remote_temp_dir/output.json" "$MACHINES_PATH/machines/$hostname/install-result.json"

# TODO: ensure the working directory is set correctly
print_info "Gathering hardware information..."
scp root@$via_host:/mnt/etc/nixos/hardware-configuration.nix "$MACHINES_PATH/machines/$hostname/"

print_info "Building target system configuration..."
nix build --file "$nixos_system_file" --argstr hostname "$hostname" --out-link "$local_temp_dir/nixos-config-$hostname"

print_info "Deploying target system configuration..."
nix copy --file "$nixos_system_file" --argstr hostname "$hostname" --to ssh://root@$via_host
nixos_config_path=$(realpath "$local_temp_dir/nixos-config-$hostname")

# TODO: merge commands
ssh root@$via_host "nixos-install --system $nixos_config_path && sync"
ssh root@$via_host mkdir --mode u=rwx,g=,o= --parents /mnt/secrets/passwords

# TODO: get host-specific password
#scp -r notThePassword root@$via_host:/mnt/secrets/passwords/root
#scp -r notThePassword root@$via_host:/mnt/secrets/passwords/jens

ssh root@$via_host sync

print_info "Installation completed"