#!/usr/bin/ruby -wKU
#
# mailshears, to prune unused mail directories.
#
# Mail accounts for virtual hosts are stored in SQL, and managed by
# Postfixadmin. However, the physical directories are handled by
# Postfix/Dovecot and are left untouched by Postfixadmin. This is good
# for security, but comes at a cost: Postfixadmin can't remove a
# user's mail directory when his or her account is deleted.
#
# This program compares the list of filesystem accounts with the ones
# in the database. It outputs any accounts that exist in the
# filesystem, but not the database.
#

# Define a usage string using the program name.
exe = File.basename($PROGRAM_NAME)
usage = "#{exe} [prune | rm <target> | mv <src> <dst>]"

# Defaults
mode_name = 'prune'
mode = :prune

# Now, if a mode was supplied, it should be in ARGV[0].
if ARGV.length() > 0
  mode_names = ['prune', 'rm', 'mv']
  if mode_names.include?(ARGV.first().downcase()) then
    # Peel the mode name off the head of the list.
    mode_name = ARGV.shift()
  end
end

if mode_name == 'rm' then
  mode = :rm
elsif mode_name == 'mv' then
  mode = :mv
end

# Need this before referencing ExitCodes.
require 'mailshears'

# Since we removed both the executable name and the mode name (if it
# existed) from ARGV, what remains should be the required
# arguments.
if (mode == :prune and (ARGV.length() != 0)) or
    (mode == :rm and (ARGV.length() < 1))   or
    (mode == :mv and (ARGV.length() != 2))   then
  puts "ERROR: missing (or extra) command-line arguments."
  puts "Usage: #{usage}"
  Kernel.exit(ExitCodes::BAD_COMMAND_LINE)
end

cfg = Configuration.new()

# Load each of the plugins that we'll need.
cfg.plugins.each do |plugin_file|
  require "#{mode_name}/plugins/#{plugin_file}"
end

# Always enabled, for now.
require "#{mode_name}/plugins/postfixadmin_db"

# And the runners.
require "#{mode_name}/#{mode_name}_runner"
require "#{mode_name}/#{mode_name}_dummy_runner"

def make_header(plugin_name)
  # The header that we output before the list of domains/accounts.
  # Just the path of this script, the current time, and the plugin name.
  exe = File.basename($PROGRAM_NAME)
  header = "#{exe}, "

  current_time = Time.now()
  if current_time.respond_to?(:iso8601)
    # Somehow this method is missing on some machines.
    header += current_time.iso8601.to_s
  else
    # Fall back to whatever this looks like.
    header += current_time.to_s
  end

  header += ' (Plugin: ' + plugin_name + ")\n"
  header += '-' * header.size # Underline the header.

  return header
end


plugin_class = nil
runner_class = nil
dummy_runner_class = nil

if mode == :rm then
  plugin_class = RmPlugin
  runner_class = RmRunner
  dummy_runner_class = RmDummyRunner
elsif mode == :mv then
  plugin_class = MvPlugin
  runner_class = MvRunner
  dummy_runner_class = MvDummyRunner
else
  # Safe, catch-all default
  plugin_class = PrunePlugin
  runner_class = PruneRunner
  dummy_runner_class = PruneDummyRunner
end

puts make_header(plugin_class.to_s())

plugin_class.includers.each do |plugin_class_includer|
  plugin = plugin_class_includer.new()

  if cfg.i_mean_business then
    runner = runner_class.new()
  else
    runner = dummy_runner_class.new()
  end

  # The splat passes the correct (we hope) number of arguments to the
  # appropriate runner. The Rm(Dummy)Runner have splats on their
  # *target arguments as well, to turn ARGV back into an array.
  runner.run(plugin, *ARGV)

  puts ""
end



Kernel.exit(0)


begin
  # Get a list of domains from the Postfixadmin database.
  db_domains = pgadb.get_domains_from_db()
rescue DatabaseError => e
  puts "There was an error connecting to the database: #{e.to_s}"
  Kernel.exit(ExitCodes::DATABASE_ERROR)
end

begin
  # And the accounts.
  db_accounts = pgadb.get_accounts_from_db()
rescue DatabaseError => e
  puts "There was an error connecting to the database: #{e.to_s}"
  Kernel.exit(ExitCodes::DATABASE_ERROR)
end


Plugin.includers.each do |plugin_class_includer|
  plugin = plugin_class_includer.new()

  begin
    leftover_domains = plugin.get_leftover_domains(db_domains)
  rescue StandardError => e
    puts "There was an error retrieving domains from the filesystem: #{e.to_s}"
    Kernel.exit(ExitCodes::FILESYSTEM_ERROR)
  end

  begin
    leftover_accounts = plugin.get_leftover_accounts(db_accounts)
  rescue StandardError => e
    puts "There was an error retrieving accounts from the filesystem: #{e.to_s}"
    Kernel.exit(ExitCodes::FILESYSTEM_ERROR)
  end

  if leftover_domains.size > 0 or leftover_accounts.size > 0
    puts make_header(plugin_class.to_s())

    leftover_domains.each do |domain|
      puts "Found: #{domain} (#{plugin.describe_domain(domain)})"
    end

    leftover_accounts.each do |account|
      puts "Found: #{account} (#{plugin.describe_account(account)})"
    end

    if cfg.i_mean_business
      # We have to delete the accounts before the domain,
      # otherwise they'd already be gone.
      leftover_accounts.each do |account|
        # Get the description before we delete the domain.
        # This can still fail if the account's domain is gone.
        account_description = plugin.describe_account(account)
        plugin.delete_account(account)
        puts "Removed: #{account} (#{account_description})"
      end

      leftover_domains.each do |domain|
        # Get the description before we delete the domain.
        domain_description = plugin.describe_domain(domain)
        plugin.delete_domain(domain)
        puts "Removed: #{domain} (#{domain_description})"
      end
    end

    puts ""
  end

end