# Command-line interface
# Copyright (C) 2023  Nguyễn Gia Phong
#
# This file if part of hybring.
#
# Hybring is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Hybring is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with hybring.  If not, see <https://www.gnu.org/licenses/>.

require "ini"
require "option_parser"

require "./http"

enum Subcommand
  Serve
  Usage
end

struct Configuration
  @sock : String
  getter sock
  @db : Path
  getter db
  @css : Path
  getter css

  @opennic_local : Path
  getter opennic_local
  @opennic_remote : String
  getter opennic_remote
  @opennic_api : String
  getter opennic_api

  @icann_local : Path
  getter icann_local
  @icann_remote : String
  getter icann_remote
  @icann_api : String
  getter icann_api

  def initialize(ini)
    @sock = ini["general"]["sock"]
    @db = Path[ini["general"]["db"]]
    @css = Path[ini["general"]["css"]]

    @opennic_local = Path[ini["opennic"]["local"]]
    @opennic_remote = ini["opennic"]["remote"]
    @opennic_api = ini["opennic"]["api"]

    @icann_local = Path[ini["icann"]["local"]]
    @icann_remote = ini["icann"]["remote"]
    @icann_api = ini["icann"]["api"]
  end
end

def die(error)
  STDERR << error
  exit 1
end

{% unless @top_level.constant("SPEC") %}
  subcmd = Subcommand::Usage
  usage = ""
  config_path, port = nil, 0

  parser = OptionParser.new do |parser|
    banner_prefix = "Usage: #{Path[PROGRAM_NAME].basename}"
    parser.banner = "#{banner_prefix} [subcommand] [arguments]"
    parser.on "serve", "start the HTTP server"  do
      subcmd = Subcommand::Serve
      parser.banner = "#{banner_prefix} serve --config=PATH [--port=N]"
      usage = parser.to_s
      parser.on "-c PATH", "--config=PATH",
                "path to configuration file (required)" do |path|
        config_path = path
      end
      parser.on "-p N", "--port=N", "listening port" do |n|
        port = n.to_i
      end
    end
    parser.on "-h", "--help", "show this help message and exit"  do
      puts parser
      exit
    end

    parser.invalid_option do |flag|
      STDERR.puts "Error: Invalid option: #{flag}"
      subcmd = Subcommand::Usage
    end
    parser.missing_option do |flag|
      STDERR.puts "Error: Missing argument for #{flag}"
      subcmd = Subcommand::Usage
    end
    parser.unknown_args do |before_dash, after_dash|
      next if before_dash.empty? && after_dash.empty?
      STDERR << "Error: Unknown arguments:"
      STDERR << " " << before_dash.join " "  if !before_dash.empty?
      STDERR << " -- " << after_dash.join " "  if !after_dash.empty?
      STDERR.puts
      subcmd = Subcommand::Usage
    end
  end

  parser.parse
  cfg = case subcmd
        when .serve?
          unless config_path
            die usage
          end
          begin
            Configuration.new INI.parse File.read config_path.not_nil!
          rescue ex
            die "Error: Failed to read config from #{config_path}: #{ex}\n"
          end
        end

  case subcmd
  in .serve?
    server = Server.new cfg.not_nil!
    server.listen port do |address|
      puts "Listening on #{address}"
    end
  in .usage?
    die parser
  end
{% end %}