import {z} from 'zod'

export type Investment = {T: string, A: number};

export type Portfolio = Array<Investment>;

export type CreateApiPortfolioExposuresArgs = {body: {portfolio?: Array<Portfolio> | undefined}};

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

export const getPortfolioExposuresResponse = z.object({exposure_dicts: z.object({country: z.record(z.string(), z.number()).optional(), sector: z.record(z.string(), z.number()).optional(), holding: z.record(z.string(), z.number()).optional()}).optional(), country_exposure_chart_markdown: z.string().optional(), sector_exposure_chart_markdown: z.string().optional(), holding_exposure_chart_markdown: z.string().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
};

/**
 * Get sector, country, and holding exposures for the given portfolio and the markdown of respective charts
 * 
 * POST /portfolio_exposures
 */
export const createApiPortfolioExposures = async (args: CreateApiPortfolioExposuresArgs, options?: CreateApiPortfolioExposuresOptions) => {
const {baseUrl = "https://portfoliopilot.com/api/gpt", 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 = `${baseUrl.replace(/\/+$/, '')}/portfolio_exposures${query.size > 0 ? `?${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(getPortfolioExposuresResponse, await res.json())
};