import type { DeviceType, MODBUS_COMSET, MeterTemplateUsage } from "@/types/evcc";
import { ConfigType } from "@/types/evcc";
import api from "@/api";
import { extractPlaceholders, replacePlaceholders } from "@/utils/placeholder";

// config write needs the admin password (script plugin)
export const ADMIN_PASSWORD_REQUIRED = 428;

const allowAdminPasswordRequired = (status: number) =>
  (status >= 200 && status < 300) || status === ADMIN_PASSWORD_REQUIRED;

function adminPasswordHeader(adminPassword = ""): Record<string, string> {
  return adminPassword ? { "X-Admin-Password": adminPassword } : {};
}

export type Product = {
  group: string;
  name: string;
  template: string;
};

export type Template = {
  Params: TemplateParam[];
  Auth?: {
    type: string;
    params?: string[];
  };
  Requirements: {
    Description: string;
  };
};

export type TemplateParamUsage = "vehicle" | "battery" | "grid" | "pv" | "charger" | "aux" | "ext";

export type TemplateParam = {
  Name: string;
  Required: boolean;
  Advanced: boolean;
  Deprecated: boolean;
  Default?: string | number | boolean;
  Type?: string;
  Choice?: string[];
  Service?: string;
  Usages?: TemplateParamUsage[];
};

export type ParamService = {
  name: string;
  service: string;
  url: (values: Record<string, any>) => string;
};

export type ModbusCapability = "rs485" | "tcpip";

export type ModbusParam = TemplateParam & {
  ID?: string;
  Comset?: MODBUS_COMSET;
  Baudrate?: number;
  Port?: number;
};

export type DeviceValues = {
  type: ConfigType;
  icon?: string;
  deviceProduct?: string;
  yaml?: string;
  template: string | null;
  deviceTitle?: string;
  deviceIcon?: string;
  deviceDisable?: boolean;
  usage?: MeterTemplateUsage;
  heating?: boolean;
  integrateddevice?: boolean;
  stationid?: string;
  [key: string]: any;
};

export type ApiData = {
  type?: ConfigType;
  icon?: string;
  usage?: MeterTemplateUsage;
  title?: string;
  priority?: number;
  identifiers?: string[];
  [key: string]: any;
};

export type AuthCheckResponse = {
  success: boolean;
  error?: string;
  authId?: string;
};

export function handleError(e: any, msg: string) {
  console.error(e);
  let message = msg;
  const { error } = e.response.data || {};
  if (error) message += `: ${error}`;
  alert(message);
}

export function applyDefaultsFromTemplate(template: Template | null, values: DeviceValues) {
  const params = template?.Params || [];
  params.forEach((p) => {
    if (p.Default && !values[p.Name]) {
      values[p.Name] = p.Default;
    } else if (p.Type === "Bool" && values[p.Name] === undefined) {
      values[p.Name] = false; // initialize
    }
  });
}

export function customChargerName(type: ConfigType, isHeating: boolean) {
  if (!type) {
    return "config.general.customOption";
  }
  const prefix = "config.charger.type.";
  const suffix = isHeating ? ".heating" : ".charging";
  if (type === ConfigType.Custom) {
    return `${prefix}custom${suffix}`;
  }
  return `${prefix}${type}`;
}

// flattenDeviceConfig converts a GET /config/devices/:class/:id response
// into the flat shape expected by POST/PUT/test (id and name are dropped).
//
// GET (config = device-specfic):
//   {
//     id: 26,
//     name: "db:26",
//     type: "template",
//     deviceTitle: "Espresso",
//     device__: "..",
//     config: {
//       template: "tasmota",
//       host: "192.168.1.2"
//     }
//   }
//
// PUT|POST|test (flat):
//   {
//     type: "template",
//     deviceTitle: "Espresso",
//     device__: "..",
//     template: "tasmota",
//     host: "192.168.1.2"
//   }
//
// TODO: align GET and PUT shapes — always nest device-specific values under
// `config` and drop the artificial `device` prefix (deviceTitle → title, ...)
// matching db structure. Once the API is symmetric this helper goes away.
export function flattenDeviceConfig(dev: any): Record<string, any> {
  const { id, name, config, ...rest } = dev;
  const flat = { ...config, ...rest };
  // title/icon are extracted from yaml on GET for display only; writing them
  // back is rejected ("cannot mix yaml and other")
  if (flat.yaml) {
    delete flat.title;
    delete flat.icon;
  }
  return flat;
}

export async function loadServiceValues(path: string) {
  try {
    const response = await api.get(`/config/service/${path}`, {
      validateStatus: (status) => status >= 200 && status < 500,
    });
    return (response.data as string[]) || [];
  } catch {
    return [];
  }
}

// Expand {modbus} to actual connection params based on values
const expandModbus = (service: string, values: Record<string, any>): string => {
  if (!service.includes("{modbus}")) return service;

  if (values["device"]) {
    return service.replace(
      "{modbus}",
      "device={device}&baudrate={baudrate}&comset={comset}&id={id}"
    );
  }
  if (values["host"]) {
    return service.replace("{modbus}", "uri={host}:{port}&id={id}");
  }
  return service;
};

export const createServiceEndpoints = (params: TemplateParam[]): ParamService[] => {
  return params
    .map((param) => {
      if (!param.Service) {
        return null;
      }
      const stringValues = (values: Record<string, any>): Record<string, string> =>
        Object.entries(values).reduce(
          (acc, [key, val]) => {
            if (val !== undefined && val !== null && val !== "" && key !== "modbus")
              acc[key] = String(val);
            return acc;
          },
          {} as Record<string, string>
        );

      return {
        name: param.Name,
        service: param.Service,
        url: (values: Record<string, any>) =>
          replacePlaceholders(expandModbus(param.Service!, values), stringValues(values)),
      } as ParamService;
    })
    .filter((endpoint): endpoint is ParamService => endpoint !== null);
};

export const fetchServiceValues = async (
  templateParams: TemplateParam[],
  values: DeviceValues
): Promise<Record<string, string[]>> => {
  const endpoints = createServiceEndpoints(templateParams);
  const result: Record<string, string[]> = {};

  await Promise.all(
    endpoints.map(async (endpoint) => {
      const url = endpoint.url(values);
      if (extractPlaceholders(url).length > 0) {
        // missing values, not all placeholders are filled
        return;
      }
      const data = await loadServiceValues(url);
      if (data) {
        result[endpoint.name] = data;
      }
    })
  );

  return result;
};

export function createDeviceUtils(deviceType: DeviceType) {
  function test(id: number | undefined, data: any, adminPassword = "") {
    let url = `config/test/${deviceType}`;
    if (id !== undefined) {
      url += `/merge/${id}`;
    }
    const opts = {
      headers: adminPasswordHeader(adminPassword),
      validateStatus: allowAdminPasswordRequired,
    };
    return api.post(url, data, opts);
  }

  function update(id: number, data: any, force = false, adminPassword = "") {
    const opts = {
      headers: adminPasswordHeader(adminPassword),
      validateStatus: allowAdminPasswordRequired,
      params: { force },
    };
    return api.put(`config/devices/${deviceType}/${id}`, data, opts);
  }

  function remove(id: number) {
    return api.delete(`config/devices/${deviceType}/${id}`);
  }

  // disable flips the disable flag by re-PUTing the existing config.
  // force=true so a broken device can still be toggled.
  async function disable(id: number, disable: boolean) {
    const dev = (await api.get(`config/devices/${deviceType}/${id}`)).data;
    const body = { ...flattenDeviceConfig(dev), deviceDisable: disable };
    return api.put(`config/devices/${deviceType}/${id}`, body, { params: { force: true } });
  }

  async function load(id: number) {
    const response = await api.get(`config/devices/${deviceType}/${id}`);
    return response.data;
  }

  function create(data: any, force = false, adminPassword = "") {
    const opts = {
      headers: adminPasswordHeader(adminPassword),
      validateStatus: allowAdminPasswordRequired,
      params: { force },
    };
    return api.post(`config/devices/${deviceType}`, data, opts);
  }

  async function loadProducts(lang?: string, usage?: string) {
    const params: Record<string, string | undefined> = { lang };
    if (usage) {
      params["usage"] = usage;
    }
    const response = await api.get(`config/products/${deviceType}`, { params });
    return response.data;
  }

  async function loadTemplate(templateName: string, lang?: string) {
    if (!templateName) return null;

    const opts = {
      params: {
        lang,
        name: templateName,
      },
    };
    const response = await api.get(`config/templates/${deviceType}`, opts);
    return response.data;
  }

  async function checkAuth(
    type: string,
    values: Record<string, any>,
    id?: number
  ): Promise<AuthCheckResponse> {
    const body = { type, ...values };
    let url = `config/auth`;
    if (id !== undefined) {
      url += `/${deviceType}/merge/${id}`;
    }
    try {
      const { status, data = {} } = await api.post(url, body, {
        validateStatus: (status) => [204, 400].includes(status),
      });
      // already set up
      if (status === 204) {
        return { success: true };
      }
      // auth error, user has to perform login
      if (status === 400) {
        return { success: false, error: data?.error, authId: data?.loginRequired };
      }
    } catch (error) {
      return { success: false, error: (error as any).message };
    }
    return { success: false, error: "unexpected error" };
  }

  return {
    test,
    update,
    remove,
    disable,
    load,
    create,
    loadProducts,
    loadTemplate,
    loadServiceValues,
    checkAuth,
  };
}