#include "plugin.h"

#include <boost/beast/version.hpp>

#include <boost/dll/import.hpp>
#include <boost/filesystem.hpp>

#include <iostream>
#include <filesystem>

namespace dll = boost::dll;
namespace fs = std::filesystem;
using namespace std::string_literals;

PluginLoader::PluginLoader(Config& config): m_config{config}
{
}

void PluginLoader::load_plugins()
{
 const auto& plugin_directories{m_config.PluginDirectories()};

 for (const auto& dir: plugin_directories) {
  for (auto& path: fs::recursive_directory_iterator(dir)) {
   if (path.is_regular_file() && path.path().extension() == ".so"s) {

    dll::fs::path lib_path{path.path()};

    try {
     boost::shared_ptr<webserver_plugin_interface> plugin = dll::import<webserver_plugin_interface>(lib_path, "webserver_plugin", dll::load_mode::append_decorations);
     if (plugin) {
      if (plugin->version() != webserver_plugin_interface::interface_version)
       throw std::runtime_error("Bad interface version for "s + path.path().generic_string() + ": "s + std::to_string(plugin->version()) + " vs. "s + std::to_string(webserver_plugin_interface::interface_version));

      std::string name{plugin->name()};
      if (m_plugins.find(name) != m_plugins.end())
       throw std::runtime_error("Plugin already exists: "s + name);

      std::cout << "Found plugin: " << name << " (" << path.path().string() << "), ";
      if (m_config.PluginIsConfigured(name)) {
       std::cout << "loading.";
       m_plugins.emplace(plugin->name(), plugin);
      } else {
       std::cout << "ignored (not configured).";
      }
      std::cout << std::endl;

     } else
      std::cout << "Can't load plugin from " << path.path().generic_string() << std::endl;
    } catch (const std::exception& ex) {
     std::cout << "Can't load plugin from " << path.path().generic_string() << ": " << ex.what() << std::endl;
    }
   }
  }
 }
}

// validate config regarding plugins
bool PluginLoader::validate_config()
{
 const auto& sites{m_config.Sites()};

 for (const auto& site: sites) {
  for (const auto& path: site.second.paths) {
   // path must contain target and plugin
   auto it {path.params.find("target")};
   if (it == path.params.end()) {
    std::cout << "Path " << path.requested << " for site " << site.first << " is missing target specification." << std::endl;
    return false;
   }

   it = path.params.find("plugin");
   if (it == path.params.end()) {
    std::cout << "Path " << path.requested << " for site " << site.first << " is missing plugin specification." << std::endl;
    return false;
   }

   std::string plugin {it->second};

   // check if plugin exists
   if (m_plugins.find(plugin) == m_plugins.end()) {
    std::cout << "Configured plugin " << plugin << " not found" << std::endl;
    return false;
   }
  }
 }
 return true;
}

plugins_container_type& PluginLoader::get_plugins()
{
 return m_plugins;
}