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#
#  http://www.apache.org/licenses/LICENSE-2.0
#
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require "pluginmanager/bundler/logstash_uninstall"
require "pluginmanager/x_pack_interceptor.rb"
require "pluginmanager/command"

class LogStash::PluginManager::Remove < LogStash::PluginManager::Command
  parameter "PLUGIN", "plugin name"

  def execute
    signal_error("File #{LogStash::Environment::GEMFILE_PATH} does not exist or is not writable, aborting") unless File.writable?(LogStash::Environment::GEMFILE_PATH)

    LogStash::Bundler.prepare({:without => [:build, :development]})

    if LogStash::PluginManager::ALIASES.has_key?(plugin)
      unless LogStash::PluginManager.installed_plugin?(plugin, gemfile)
        aliased_plugin = LogStash::PluginManager::ALIASES[plugin]
        puts "Cannot remove the alias #{plugin}, which is an alias for #{aliased_plugin}; if you wish to remove it, you must remove the aliased plugin instead."
        return
      end
    end

    # If a user is attempting to uninstall X-Pack, present helpful output to guide
    # them toward the OSS-only distribution of Logstash
    LogStash::PluginManager::XPackInterceptor::Remove.intercept!(plugin)

    # if the plugin is provided by an integration plugin. abort.
    if integration_plugin = LogStash::PluginManager.which_integration_plugin_provides(plugin, gemfile)
      signal_error("This plugin is already provided by '#{integration_plugin.name}' so it can't be removed individually")
    end

    not_installed_message = "This plugin has not been previously installed"
    plugin_gem_spec = LogStash::PluginManager.find_plugins_gem_specs(plugin).any?
    if plugin_gem_spec
      # make sure this is an installed plugin and present in Gemfile.
      # it is not possible to uninstall a dependency not listed in the Gemfile, for example a dependent codec
      signal_error(not_installed_message) unless LogStash::PluginManager.installed_plugin?(plugin, gemfile)
    else
      # locally installed plugins are not recoginized by ::Gem::Specification
      # we may ::Bundler.setup to reload but it resets all dependencies so we get error message for future bundler operations
      # error message: `Bundler::GemNotFound: Could not find rubocop-1.60.2... in locally installed gems`
      # instead we make sure Gemfile has a definition and ::Gem::Specification recognizes local gem
      signal_error(not_installed_message) unless !!gemfile.find(plugin)

      local_gem = gemfile.locally_installed_gems.detect { |local_gem| local_gem.name == plugin }
      signal_error(not_installed_message) unless local_gem
    end

    exit(1) unless ::Bundler::LogstashUninstall.uninstall!(plugin)
    LogStash::Bundler.genericize_platform
    remove_unused_locally_installed_gems!
  rescue => exception
    report_exception("Operation aborted, cannot remove plugin", exception)
  end
end