import {z} from 'zod'

export type DateRange = string | Array<string>;

export type Filter = {field: 'browser' | 'browser_version' | 'os' | 'os_version' | 'device' | 'country' | 'city' | 'region' | 'hostname' | 'utm_source' | 'utm_medium' | 'utm_campaign' | 'utm_content' | 'utm_term' | 'entry_page' | 'exit_page' | 'source' | 'channel' | 'referrer' | 'page' | 'code' | 'event', operator: 'is' | 'is_not' | 'contains' | 'does_not_contain', values: Array<string>};

export type FunnelReportRequest = {site_id?: number | undefined, date_range: DateRange, filters?: Array<Filter> | undefined};

export type CreateApiFunnelsIdReportArgs = {id: number, body: FunnelReportRequest};

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

export const funnelReportStep = z.object({index: z.number().int().optional(), name: z.string().optional(), kind: z.enum(["page", "event", "goal", "scroll", "entry_page", "exit_page"]).optional(), visitors: z.number().int().optional(), conversion_rate: z.number().optional(), dropoff: z.number().int().optional()});

export const funnelReportResponse = z.object({funnel: z.object({id: z.number().int().optional(), name: z.string().optional(), scope: z.enum(["visitor", "session"]).optional(), strict_order: z.boolean().optional()}).optional(), entering: z.number().int().optional(), all_visitors: z.number().int().optional(), steps: z.array(funnelReportStep).optional(), query: z.object({}).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
};

/**
 * Run a saved funnel and return per-step conversions
 * 
 * POST /funnels/{id}/report
 */
export const createApiFunnelsIdReport = async (args: CreateApiFunnelsIdReportArgs, options?: CreateApiFunnelsIdReportOptions) => {
const {baseUrl = "https://statable.com/api/v1", fetch: fetchFn = fetch, bearerAuth} = options ?? {}

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

if (bearerAuth !== undefined) headers.set('authorization', `Bearer ${bearerAuth}`)

const url = `${baseUrl.replace(/\/+$/, '')}/funnels/${encodeURIComponent(String(args.id))}/report${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(funnelReportResponse, await res.json())
};