#include "web_server.h"

#include <fstream>
#include <sstream>

#include "config/config_manager.h"
#include "nlohmann/json.hpp"
#include "spdlog/spdlog.h"

WebServer::WebServer(SystemMonitor::SystemMonitor &monitor,
                     DeviceManager &deviceManager, LiveDataCache &liveDataCache,
                     AlarmService &alarm_service, uint16_t port)
    : crow::Crow<crow::CORSHandler>(), m_monitor(monitor),
      m_device_manager(deviceManager), m_live_data_cache(liveDataCache),
      m_alarm_service(alarm_service), m_port(port) {
  auto &cors = this->get_middleware<crow::CORSHandler>();
  cors.global()
      .origin("*")
      .headers("Content-Type", "Authorization")
      .methods("GET"_method, "POST"_method, "OPTIONS"_method);

  this->loglevel(crow::LogLevel::Warning);
  setup_routes();
}

WebServer::~WebServer() { stop(); }

void WebServer::start() {
  if (m_thread.joinable()) {
    spdlog::warn("Web server is already running.");
    return;
  }
  m_thread = std::thread([this]() {
    spdlog::info("Starting Web server on port {}", m_port);
    this->bindaddr("0.0.0.0").port(m_port).run();
    spdlog::info("Web server has stopped.");
  });
}

void WebServer::stop() {
  crow::Crow<crow::CORSHandler>::stop();
  if (m_thread.joinable()) {
    m_thread.join();
  }
}

void WebServer::set_shutdown_handler(std::function<void()> handler) {
  m_shutdown_handler = handler;
}

bool WebServer::validate_video_config(const std::string &json_string,
                                      std::string &error_message) {
  try {
    auto config = nlohmann::json::parse(json_string);

    if (!config.is_object()) {
      error_message = "Root is not an object.";
      return false;
    }

    // 1. 验证 'video_service'
    if (!config.contains("video_service") ||
        !config["video_service"].is_object()) {
      error_message = "Missing 'video_service' object.";
      return false;
    }
    if (!config["video_service"].contains("enabled") ||
        !config["video_service"]["enabled"].is_boolean()) {
      error_message = "'video_service' must have 'enabled' (boolean).";
      return false;
    }

    // 2. 验证 'video_streams'
    if (!config.contains("video_streams") ||
        !config["video_streams"].is_array()) {
      error_message = "Missing 'video_streams' array.";
      return false;
    }

    // 3. 验证 'video_streams' 中的每个元素
    for (const auto &stream : config["video_streams"]) {
      if (!stream.is_object()) {
        error_message = "Item in 'video_streams' is not an object.";
        return false;
      }
      // 检查必需的键
      for (const char *key : {"id", "input_url", "module_type"}) {
        if (!stream.contains(key) || !stream[key].is_string() ||
            stream[key].get<std::string>().empty()) {
          error_message =
              "Stream missing or invalid key: '" + std::string(key) + "'.";
          return false;
        }
      }
      if (!stream.contains("enabled") || !stream["enabled"].is_boolean()) {
        error_message = "Stream missing or invalid key: 'enabled' (boolean).";
        return false;
      }
      if (!stream.contains("module_config") ||
          !stream["module_config"].is_object()) {
        error_message = "Stream missing 'module_config' (object).";
        return false;
      }

      // 4. 验证 'module_config' 的关键字段
      const auto &mod_cfg = stream["module_config"];
      for (const char *key : {"model_path", "label_path"}) {
        if (!mod_cfg.contains(key) || !mod_cfg[key].is_string() ||
            mod_cfg[key].get<std::string>().empty()) {
          error_message =
              "module_config missing or empty key: '" + std::string(key) + "'.";
          return false;
        }
      }
      if (!mod_cfg.contains("class_num") ||
          !mod_cfg["class_num"].is_number_integer() ||
          mod_cfg["class_num"].get<int>() <= 0) {
        error_message = "module_config missing or invalid 'class_num' (must be "
                        "integer > 0).";
        return false;
      }
      if (!mod_cfg.contains("rknn_thread_num") ||
          !mod_cfg["rknn_thread_num"].is_number_integer()) {
        error_message = "module_config missing 'rknn_thread_num' (integer).";
        return false;
      }
    }

    return true; // 所有检查通过

  } catch (const nlohmann::json::parse_error &e) {
    error_message = "Invalid JSON: " + std::string(e.what());
    return false;
  } catch (const std::exception &e) {
    error_message = "Validation error: " + std::string(e.what());
    return false;
  }
}

bool WebServer::validate_main_config(const std::string &json_string,
                                     std::string &error_message) {
  try {
    auto config = nlohmann::json::parse(json_string);

    if (!config.is_object()) {
      error_message = "Root is not an object.";
      return false;
    }

    // 1. 必需的字符串类型
    for (const char *key :
         {"device_id", "config_base_path", "mqtt_broker",
          "mqtt_client_id_prefix", "data_storage_db_path", "data_cache_db_path",
          "log_level", "alarm_rules_path", "piper_executable_path",
          "piper_model_path", "video_config_path"}) {
      if (!config.contains(key) || !config[key].is_string() ||
          config[key].get<std::string>().empty()) {
        error_message =
            "Missing or invalid/empty string key: '" + std::string(key) + "'.";
        return false;
      }
    }

    // 2. 必需的整数类型
    if (!config.contains("web_server_port") ||
        !config["web_server_port"].is_number_integer()) {
      error_message = "Missing or invalid 'web_server_port' (must be integer).";
      return false;
    }

    // 3. 必需的数组类型
    if (!config.contains("tcp_server_ports") ||
        !config["tcp_server_ports"].is_array()) {
      error_message = "Missing or invalid 'tcp_server_ports' (must be array).";
      return false;
    }
    for (const auto &port : config["tcp_server_ports"]) {
      if (!port.is_number_integer()) {
        error_message = "Item in 'tcp_server_ports' is not an integer.";
        return false;
      }
    }

    return true; // 所有检查通过

  } catch (const nlohmann::json::parse_error &e) {
    error_message = "Invalid JSON: " + std::string(e.what());
    return false;
  } catch (const std::exception &e) {
    error_message = "Validation error: " + std::string(e.what());
    return false;
  }
}

void WebServer::setup_routes() {

  CROW_ROUTE((*this), "/api/system/id").methods("GET"_method)([this] {
    auto deviceID = ConfigManager::getInstance().getDeviceID();
    crow::json::wvalue response;
    response["deviceID"] = deviceID;
    return response;
  });

  CROW_ROUTE((*this), "/api/system/status").methods("GET"_method)([this] {
    auto cpu_util = m_monitor.getCpuUtilization();
    auto mem_info = m_monitor.getMemoryInfo();

    crow::json::wvalue response;
    response["cpu_usage_percentage"] = cpu_util.totalUsagePercentage;
    response["memory_total_kb"] = mem_info.total_kb;
    response["memory_free_kb"] = mem_info.available_kb;
    response["memory_usage_percentage"] =
        (mem_info.total_kb > 0)
            ? (1.0 -
               static_cast<double>(mem_info.available_kb) / mem_info.total_kb) *
                  100.0
            : 0.0;

    return response;
  });

  CROW_ROUTE((*this), "/api/devices").methods("GET"_method)([this] {
    auto devices_info = m_device_manager.get_all_device_info();

    std::vector<crow::json::wvalue> devices_json;
    for (const auto &info : devices_info) {
      crow::json::wvalue device_obj;

      device_obj["id"] = info.id;
      device_obj["type"] = info.type;
      device_obj["is_running"] = info.is_running;

      crow::json::wvalue details_obj;
      for (const auto &pair : info.connection_details) {
        details_obj[pair.first] = pair.second;
      }
      device_obj["connection_details"] = std::move(details_obj);

      devices_json.push_back(std::move(device_obj));
    }
    auto res = crow::response(crow::json::wvalue(devices_json));
    res.set_header("Content-Type", "application/json");
    return res;
  });

  CROW_ROUTE((*this), "/api/data/latest").methods("GET"_method)([this] {
    auto latest_data_map = m_live_data_cache.get_all_data();

    crow::json::wvalue response;
    for (const auto &pair : latest_data_map) {
      response[pair.first] = crow::json::load(pair.second);
    }
    auto res = crow::response(response);
    res.set_header("Content-Type", "application/json");
    return res;
  });

  CROW_ROUTE((*this), "/api/alarms/active").methods("GET"_method)([this] {
    try {
      auto json_string = m_alarm_service.getActiveAlarmsJson().dump();

      auto res = crow::response(200, json_string);
      res.set_header("Content-Type", "application/json");
      return res;

    } catch (const std::exception &e) {
      spdlog::error("Error processing /api/alarms/active: {}", e.what());
      crow::json::wvalue error_resp;
      error_resp["error"] = "Failed to retrieve active alarms.";

      auto res = crow::response(500, error_resp.dump());
      res.set_header("Content-Type", "application/json");
      return res;
    }
  });

  CROW_ROUTE((*this), "/api/alarms/history")
      .methods("GET"_method)([this](const crow::request &req) {
        int limit = 100;
        if (req.url_params.get("limit")) {
          try {
            limit = std::stoi(req.url_params.get("limit"));
          } catch (const std::exception &) { /* ignore invalid */
          }
        }
        if (limit <= 0)
          limit = 100;

        try {
          auto json_string = m_alarm_service.getAlarmHistoryJson(limit).dump();

          auto res = crow::response(200, json_string);
          res.set_header("Content-Type", "application/json");
          return res;

        } catch (const std::exception &e) {
          spdlog::error("Error processing /api/alarms/history: {}", e.what());
          crow::json::wvalue error_resp;
          error_resp["error"] = "Failed to retrieve alarm history.";

          auto res = crow::response(500, error_resp.dump());
          res.set_header("Content-Type", "application/json");
          return res;
        }
      });

  CROW_ROUTE((*this), "/api/alarms/reload").methods("POST"_method)([this]() {
    spdlog::info("Web API: Received request to reload alarm rules...");

    bool success = m_alarm_service.reload_rules();

    if (success) {
      crow::json::wvalue response_json;
      response_json["status"] = "success";
      response_json["message"] = "Alarm rules reloaded successfully.";

      auto res = crow::response(200, response_json.dump());
      res.set_header("Content-Type", "application/json");
      return res;

    } else {
      crow::json::wvalue error_json;
      error_json["status"] = "error";
      error_json["message"] =
          "Failed to reload alarm rules. Check service logs for details.";
      auto res = crow::response(500, error_json.dump());
      res.set_header("Content-Type", "application/json");
      return res;
    }
  });

  CROW_ROUTE((*this), "/api/alarms/clear")
      .methods("POST"_method)([this](const crow::request &req) {
        crow::json::rvalue j_body;
        try {
          j_body = crow::json::load(req.body);
        } catch (const std::exception &e) {
          spdlog::warn("Failed to parse request body for /api/alarms/clear: {}",
                       e.what());
          auto res = crow::response(400, "{\"error\":\"Invalid JSON body.\"}");
          res.set_header("Content-Type", "application/json");
          return res;
        }

        if (!j_body.has("rule_id") || !j_body.has("device_id")) {
          auto res = crow::response(
              400, "{\"error\":\"Missing 'rule_id' or 'device_id'.\"}");
          res.set_header("Content-Type", "application/json");
          return res;
        }

        std::string rule_id = j_body["rule_id"].s();
        std::string device_id = j_body["device_id"].s();

        bool success = m_alarm_service.manually_clear_alarm(rule_id, device_id);

        if (success) {
          auto res = crow::response(
              200, "{\"status\":\"success\", \"message\":\"Alarm cleared.\"}");
          res.set_header("Content-Type", "application/json");
          return res;
        } else {
          auto res = crow::response(
              404, "{\"status\":\"error\", \"message\":\"Alarm not "
                   "found or not active.\"}");
          res.set_header("Content-Type", "application/json");
          return res;
        }
      });

  CROW_ROUTE((*this), "/api/alarms/config").methods("GET"_method)([this]() {
    std::string rules_json_string = m_alarm_service.get_rules_as_json_string();
    auto res = crow::response(200, rules_json_string);
    res.set_header("Content-Type", "application/json");
    return res;
  });

  CROW_ROUTE((*this), "/api/alarms/config")
      .methods("POST"_method)([this](const crow::request &req) {
        const std::string &new_rules_content = req.body;

        bool success =
            m_alarm_service.save_rules_from_json_string(new_rules_content);

        if (success) {
          crow::json::wvalue response_json;
          response_json["status"] = "success";
          response_json["message"] =
              "Rules saved successfully. A reload is required to apply.";

          auto res = crow::response(200, response_json.dump());
          res.set_header("Content-Type", "application/json");
          return res;

        } else {
          crow::json::wvalue error_json;
          error_json["status"] = "error";
          error_json["message"] =
              "Failed to save rules. Invalid JSON format or server error.";

          auto res = crow::response(400, error_json.dump());
          res.set_header("Content-Type", "application/json");
          return res;
        }
      });

  /**
   * @brief GET /api/devices/config
   * 获取设备配置 (devices.json) 的原始 JSON 字符串
   */
  CROW_ROUTE((*this), "/api/devices/config").methods("GET"_method)([this]() {
    std::string rules_json_string =
        m_device_manager.get_config_as_json_string();
    auto res = crow::response(200, rules_json_string);
    res.set_header("Content-Type", "application/json");
    return res;
  });

  /**
   * @brief POST /api/devices/config
   * 保存设备配置 (devices.json) 的原始 JSON 字符串
   */
  CROW_ROUTE((*this), "/api/devices/config")
      .methods("POST"_method)([this](const crow::request &req) {
        const std::string &new_rules_content = req.body;

        // save_config_from_json_string 内部包含 JSON 格式和 Schema 校验
        bool success =
            m_device_manager.save_config_from_json_string(new_rules_content);

        if (success) {
          crow::json::wvalue response_json;
          response_json["status"] = "success";
          response_json["message"] = "Device config saved successfully. A "
                                     "reload is required to apply.";

          auto res = crow::response(200, response_json.dump());
          res.set_header("Content-Type", "application/json");
          return res;

        } else {
          crow::json::wvalue error_json;
          error_json["status"] = "error";
          error_json["message"] = "Failed to save rules. Invalid JSON format "
                                  "or schema. Check service logs.";

          auto res = crow::response(400, error_json.dump());
          res.set_header("Content-Type", "application/json");
          return res;
        }
      });

  /**
   * @brief POST /api/devices/reload
   * 通知后端从磁盘重载 devices.json 并应用
   */
  CROW_ROUTE((*this), "/api/devices/reload").methods("POST"_method)([this]() {
    spdlog::info("Web API: Received request to reload device rules...");

    bool success = m_device_manager.reload_config_from_file();

    if (success) {
      crow::json::wvalue response_json;
      response_json["status"] = "success";
      response_json["message"] = "Device rules reload posted successfully.";

      auto res = crow::response(200, response_json.dump());
      res.set_header("Content-Type", "application/json");
      return res;

    } else {
      crow::json::wvalue error_json;
      error_json["status"] = "error";
      error_json["message"] =
          "Failed to post device rules reload. Check service logs.";
      auto res = crow::response(500, error_json.dump());
      res.set_header("Content-Type", "application/json");
      return res;
    }
  });

  /**
   * @brief GET /api/video_config
   * 获取 video_config.json 的原始 JSON 字符串
   */
  CROW_ROUTE((*this), "/api/video_config").methods("GET"_method)([this]() {
    std::string config_path;
    try {

      config_path = ConfigManager::getInstance().getVideoConfigPath();
    } catch (const std::exception &e) {
      spdlog::error("Failed to get video config path from ConfigManager: {}",
                    e.what());
      auto res = crow::response(500, "{\"error\":\"Server configuration error: "
                                     "cannot determine config path.\"}");
      res.set_header("Content-Type", "application/json");
      return res;
    }

    std::ifstream ifs(config_path);
    if (!ifs.is_open()) {
      spdlog::error("Failed to open video config file for reading: {}",
                    config_path);
      auto res =
          crow::response(404, "{\"error\":\"Video config file not found.\"}");
      res.set_header("Content-Type", "application/json");
      return res;
    }

    std::string content((std::istreambuf_iterator<char>(ifs)),
                        (std::istreambuf_iterator<char>()));

    auto res = crow::response(200, content);
    res.set_header("Content-Type", "application/json");
    return res;
  });

  /**
   * @brief POST /api/video_config
   * 验证并保存 video_config.json
   */
  CROW_ROUTE((*this), "/api/video_config")
      .methods("POST"_method)([this](const crow::request &req) {
        const std::string &new_config_content = req.body;
        std::string error_msg;

        if (!validate_video_config(new_config_content, error_msg)) {
          spdlog::warn("Web API: Failed to save video_config: {}", error_msg);
          crow::json::wvalue error_json;
          error_json["status"] = "error";
          error_json["message"] = "Invalid JSON format or schema: " + error_msg;
          auto res = crow::response(400, error_json.dump());
          res.set_header("Content-Type", "application/json");
          return res;
        }

        std::string config_path =
            ConfigManager::getInstance().getVideoConfigPath();

        std::ofstream ofs(config_path);
        if (!ofs.is_open()) {
          spdlog::error("Failed to open video config file for writing: {}",
                        config_path);
          auto res = crow::response(
              500, "{\"error\":\"Failed to write config file on server.\"}");
          res.set_header("Content-Type", "application/json");
          return res;
        }

        auto json_data = nlohmann::json::parse(new_config_content);
        ofs << json_data.dump(4); // 格式化写入
        ofs.close();

        // 4. 成功响应
        spdlog::info("Video config successfully updated via API at {}",
                     config_path);
        crow::json::wvalue response_json;
        response_json["status"] = "success";
        response_json["message"] =
            "Video config saved. Send POST to /api/service/reload to apply.";
        auto res = crow::response(200, response_json.dump());
        res.set_header("Content-Type", "application/json");
        return res;
      });

  CROW_ROUTE((*this), "/api/service/reload").methods("POST"_method)([this]() {
    if (m_shutdown_handler) {
      spdlog::info("Web API: Received request to reload service...");
      m_shutdown_handler();

      auto res =
          crow::response(202, "{\"status\":\"restarting\", "
                              "\"message\":\"Service is restarting...\"}");
      res.set_header("Content-Type", "application/json");
      return res;
    }

    spdlog::error("Web API: /api/service/reload called, but shutdown handler "
                  "is not set!");
    auto res = crow::response(
        500, "{\"error\":\"Shutdown handler not configured on server.\"}");
    res.set_header("Content-Type", "application/json");
    return res;
  });


  /**
   * @brief GET /api/config
   * 获取主 config.json 的原始 JSON 字符串
   */
  CROW_ROUTE((*this), "/api/config").methods("GET"_method)([this]() {
    std::string config_path;
    try {
      // 1. 从 ConfigManager 获取路径
      config_path = ConfigManager::getInstance().getConfigFilePath();
      if (config_path.empty()) {
        throw std::runtime_error("ConfigManager returned an empty path.");
      }
    } catch (const std::exception &e) {
      spdlog::error("Failed to get main config path from ConfigManager: {}",
                    e.what());
      auto res = crow::response(500, "{\"error\":\"Server configuration error: "
                                     "cannot determine config path.\"}");
      res.set_header("Content-Type", "application/json");
      return res;
    }

    // 2. 读取文件
    std::ifstream ifs(config_path);
    if (!ifs.is_open()) {
      spdlog::error("Failed to open main config file for reading: {}",
                    config_path);
      auto res =
          crow::response(404, "{\"error\":\"Main config file not found.\"}");
      res.set_header("Content-Type", "application/json");
      return res;
    }

    // 3. 返回内容
    std::string content((std::istreambuf_iterator<char>(ifs)),
                        (std::istreambuf_iterator<char>()));

    auto res = crow::response(200, content);
    res.set_header("Content-Type", "application/json");
    return res;
  });

  /**
   * @brief POST /api/config
   * 验证并保存主 config.json
   */
  CROW_ROUTE((*this), "/api/config")
      .methods("POST"_method)([this](const crow::request &req) {
        const std::string &new_config_content = req.body;
        std::string error_msg;

        if (!validate_main_config(new_config_content, error_msg)) {
          spdlog::warn("Web API: Failed to save main config: {}", error_msg);
          crow::json::wvalue error_json;
          error_json["status"] = "error";
          error_json["message"] = "Invalid JSON format or schema: " + error_msg;
          auto res = crow::response(400, error_json.dump());
          res.set_header("Content-Type", "application/json");
          return res;
        }

        std::string config_path =
            ConfigManager::getInstance().getConfigFilePath();
        if (config_path.empty()) {
          auto res = crow::response(
              500, "{\"error\":\"Failed to get config file path on server.\"}");
          res.set_header("Content-Type", "application/json");
          return res;
        }

        std::ofstream ofs(config_path);
        if (!ofs.is_open()) {
          spdlog::error("Failed to open main config file for writing: {}",
                        config_path);
          auto res = crow::response(
              500, "{\"error\":\"Failed to write config file on server.\"}");
          res.set_header("Content-Type", "application/json");
          return res;
        }

        try {
          auto json_data = nlohmann::json::parse(new_config_content);
          ofs << json_data.dump(4); 
          ofs.close();
        } catch (const std::exception &e) {
          spdlog::error("Failed to re-parse and dump main config: {}",
                        e.what());
          auto res = crow::response(
              500, "{\"error\":\"Failed to serialize config for writing.\"}");
          res.set_header("Content-Type", "application/json");
          return res;
        }

        spdlog::info("Main config successfully updated via API at {}",
                     config_path);
        crow::json::wvalue response_json;
        response_json["status"] = "success";
        response_json["message"] =
            "Main config saved. A full service restart (e.g., via "
            "/api/service/reload) is required to apply changes.";
        auto res = crow::response(200, response_json.dump());
        res.set_header("Content-Type", "application/json");
        return res;
      });
}