#!/usr/bin/env ruby

# USAGE:
# * db postgres://xxx               # with connection url
# * db (echo $DATABASE_URL)         # with subshell
# * db heroku                       # same as: db (heroku config:get DATABASE_URL)
# * db heroku:production catalog    # same as: db (heroku config:get CATALOG_DATABASE_URL -r production)
# * db development                  # specific env from database.yml

require "yaml"
require "fileutils"
require "uri"

arg = ARGV.fetch(0, "development")

def clean(hash)
  hash.reject do |key, val|
    val.nil? || val == ''
  end
end

def yml_to_config(config)
  clean \
    type: config["adapter"]&.to_sym,
    database: config["database"],
    username: config["username"],
    password: config["password"],
    port: config["port"],
    host: config["host"]
end

def uri_to_config(uri)
  uri = URI(uri)
  clean \
    type: uri.scheme.to_sym,
    database: uri.path[1..-1],
    username: uri.user,
    password: URI.unescape(uri.password.to_s),
    port: uri.port,
    host: uri.host
end

db = case arg.downcase
  when lambda { |a| a.start_with?("postgres://", "mysql2://") }
    uri_to_config(arg)
  when lambda { |a| a.start_with?("heroku") }
    remote = arg.split(":")[1]
    env_var = ARGV[1] ? "#{ARGV[1].upcase}_DATABASE_URL" : "DATABASE_URL"
    cmd = "heroku config:get #{env_var}"
    cmd += " -r #{remote}" if remote
    uri_to_config(`#{cmd}`.strip)
  else
    env = arg || "development"
    yml_to_config YAML.load_file(Dir.pwd + '/config/database.yml')[env]
  end

cmd = []
case db[:type]
when :postgres, :postgresql then
  cmd<< %{env PGPASSWORD="#{db[:password]}"} if db[:password]
  cmd<< "psql"
  cmd<< "-d#{db[:database]}"
  cmd<< "-U#{db[:username]}" if db[:username]
  cmd<< "-h#{db[:host]}" if db[:host]
  cmd<< "-p#{db[:port]}" if db[:port]
when :mysql2 then
  cmd<< "mysql"
  cmd<< "-h #{db[:host]}" if db[:host]
  cmd<< "-P #{db[:port]}" if db[:port]
  cmd<< "-u #{db[:username]}" if db[:username]
  cmd<< "-p#{db[:password]}" if db[:password]
  cmd<< " #{db[:database]}"
end

$stdout << cmd.join(" ")