import {z} from 'zod'

export type ToolCallParams = {name: 'att-fiber-coverage-checker' | 'att-fiber-plan-recommender' | 'att-fiber-journey-data' | 'att-device-shop' | 'att-plan-shop' | 'att-addons-accessories' | 'att-cart-checkout' | 'att-widget-api' | 'att-store-finder' | 'att-address-autocomplete' | 'att-address-validate', arguments?: {[key: string]: unknown} | undefined};

export type GenericParams = {[key: string]: unknown};

export type JsonRpcRequest = {jsonrpc: '2.0', id?: (string | number) | undefined, method: 'initialize' | 'notifications/initialized' | 'tools/list' | 'tools/call', params?: (ToolCallParams | GenericParams) | undefined};

export type CreateApiChatgptappsMcpArgs = {body: JsonRpcRequest};

export type CreateApiChatgptappsMcpOptions = {baseUrl?: string | undefined, fetch?: typeof fetch | undefined};

export const jsonRpcError = z.object({code: z.number().int(), message: z.string(), data: z.unknown()}).and(z.record(z.string(), z.unknown()));

export const jsonRpcResponse = z.object({jsonrpc: z.literal("2.0"), id: z.union([z.string(), z.number().int()]).nullable(), result: z.record(z.string(), z.unknown()).optional(), error: jsonRpcError.optional()});

export const validateResponse = async <Output>(
  schema: {
    readonly '~standard': {
      readonly validate: (value: unknown) => ({ readonly value: Output; readonly issues?: undefined } | { readonly issues: ReadonlyArray<{ readonly message: string; readonly path?: ReadonlyArray<PropertyKey | { readonly key: PropertyKey }> | undefined }> }) | Promise<{ readonly value: Output; readonly issues?: undefined } | { readonly issues: ReadonlyArray<{ readonly message: string; readonly path?: ReadonlyArray<PropertyKey | { readonly key: PropertyKey }> | undefined }> }>
    }
  },
  value: unknown
): Promise<Output> => {
  const result = await schema['~standard'].validate(value)

  if (result.issues !== undefined) {
    const detail = result.issues
      .map(({ message, path }) =>
        path?.length
          ? `${path.map((segment) => String(typeof segment === 'object' ? segment.key : segment)).join('.')}: ${message}`
          : message
      )
      .join('; ')

    throw new Error(`Response does not match the schema: ${detail}`, { cause: { issues: result.issues } })
  }

  return result.value
};

/**
 * Send an MCP JSON-RPC request
 * 
 * POST /chatgptapps/mcp
 */
export const createApiChatgptappsMcp = async (args: CreateApiChatgptappsMcpArgs, options?: CreateApiChatgptappsMcpOptions) => {
const {baseUrl = "https://myhomenetwork.att.com", fetch: fetchFn = fetch} = options ?? {}

const query = new URLSearchParams()
const headers = new Headers()
headers.set('content-type', "application/json")
headers.set('accept', "application/json")

const url = `${baseUrl.replace(/\/+$/, '')}/chatgptapps/mcp${query.size > 0 ? `?${query}` : ''}`

const res = await fetchFn(url, {method: "POST", headers, body: JSON.stringify(args.body)})

if (!res.ok) throw new Error(`Request failed with status ${res.status}`, {cause: {status: res.status, body: await res.text()}})

return validateResponse(jsonRpcResponse, await res.json())
};