import {z} from 'zod'

export type GetApiV1HistoricalArgs = {symbols: string, at: string, metric?: ('gamma' | 'vanna') | undefined, maxStrikes?: number | undefined};

export type GetApiV1HistoricalOptions = {baseUrl?: string | undefined, bearerApiKey?: string | undefined, fetch?: typeof fetch | undefined};

export const strikeNode = z.object({strike: z.number(), value: z.number(), nodeType: z.enum(["king", "gatekeeper", "pika", "barney", "significant", "normal"]), velocityPct: z.number().optional()});

export const symbolHeatmap = z.object({symbol: z.string(), asOf: z.string(), spot: z.number(), previousClose: z.number(), priceChange: z.number(), priceChangePercent: z.number(), expirations: z.array(z.string()), strikes: z.array(strikeNode)});

export const meta = z.object({timestamp: z.string(), requestId: z.string()});

export const getApiV1HistoricalResponse = z.object({data: z.object({symbols: z.array(symbolHeatmap)}), meta: meta});

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
};

/**
 * Replay per-strike heatmap at a past instant (one or more symbols)
 * 
 * GET /v1/historical
 */
export const getApiV1Historical = async (args: GetApiV1HistoricalArgs, options?: GetApiV1HistoricalOptions) => {
const {baseUrl = "https://flow-api.skylit.ai", fetch: fetchFn = fetch, bearerApiKey} = options ?? {}

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

if (args.symbols != null) query.append("symbols", String(args.symbols))
if (args.at != null) query.append("at", String(args.at))
if (args.metric != null) query.append("metric", String(args.metric))
if (args.maxStrikes != null) query.append("maxStrikes", String(args.maxStrikes))
if (bearerApiKey !== undefined) headers.set('authorization', `Bearer ${bearerApiKey}`)

const url = `${baseUrl.replace(/\/+$/, '')}/v1/historical${query.size > 0 ? `?${query}` : ''}`

const res = await fetchFn(url, {method: "GET", headers})

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

return validateResponse(getApiV1HistoricalResponse, await res.json())
};