import {z} from 'zod'

export type GetApiDexscreenerEventsArgs = {fromBlock: number, toBlock: number};

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

export const dexScreenerBlock = z.object({blockNumber: z.number().int(), blockTimestamp: z.number().int()});

export const dexScreenerSwapEvent = z.object({block: dexScreenerBlock, eventType: z.literal("swap"), txnId: z.string(), txnIndex: z.number().int(), eventIndex: z.number().int(), maker: z.string(), pairId: z.string(), asset0In: z.number().optional(), asset1In: z.number().optional(), asset0Out: z.number().optional(), asset1Out: z.number().optional(), priceNative: z.number(), reserves: z.object({asset0: z.number(), asset1: z.number()}).optional()});

export const dexScreenerEventsResponse = z.object({events: z.array(dexScreenerSwapEvent)});

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
};

/**
 * Swap events by block range
 * 
 * GET /dexscreener/events
 */
export const getApiDexscreenerEvents = async (args: GetApiDexscreenerEventsArgs, options: GetApiDexscreenerEventsOptions) => {
const {baseUrl, fetch: fetchFn = fetch, apiKey} = options ?? {}

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

if (args.fromBlock != null) query.append("fromBlock", String(args.fromBlock))
if (args.toBlock != null) query.append("toBlock", String(args.toBlock))
if (apiKey !== undefined) headers.set("X-API-Key", apiKey)

const url = `${baseUrl.replace(/\/+$/, '')}/dexscreener/events${query.size > 0 ? `?${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(dexScreenerEventsResponse, await res.json())
};