import {z} from 'zod'

export type FunnelConversionWindowUnit = 'hours' | 'days' | 'weeks';

export type ExcludeFunnelDatePresetCustom = 'last_7_days' | 'last_14_days' | 'last_30_days' | 'last_90_days' | 'last_6_months' | 'last_12_months';

export type FunnelDateRange = {preset: ExcludeFunnelDatePresetCustom, type: 'preset'} | {end: string, start: string, type: 'custom'};

export type FunnelStep = {eventName: string, stepOrder: number};

export type FunnelQueryRequest = {breakdownDimensionId?: string | undefined, conversionWindow?: {unit: FunnelConversionWindowUnit, value: number} | undefined, dateRange: FunnelDateRange, steps: Array<FunnelStep>, eventNameFieldId: string, userIdFieldId: string, timestampFieldId: string, exploreName: string};

export type CreateApiApiV1ProjectsProjectUuidFunnelQueryArgs = {projectUuid: string, body: FunnelQueryRequest};

export type CreateApiApiV1ProjectsProjectUuidFunnelQueryOptions = {baseUrl: string, fetch?: typeof fetch | undefined};

export const funnelStepResult = z.object({breakdownValue: z.string().optional(), medianTimeToConvertSeconds: z.number().nullable(), stepConversionRate: z.number(), conversionRate: z.number(), totalUsers: z.number(), stepName: z.string(), stepOrder: z.number()});

export const funnelQueryResult = z.object({sql: z.string(), steps: z.array(funnelStepResult)});

export const apiFunnelQueryResponse = z.object({results: funnelQueryResult, status: z.literal("ok")});

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 funnel query
 * 
 * POST /api/v1/projects/{projectUuid}/funnel/query
 */
export const createApiApiV1ProjectsProjectUuidFunnelQuery = async (args: CreateApiApiV1ProjectsProjectUuidFunnelQueryArgs, options: CreateApiApiV1ProjectsProjectUuidFunnelQueryOptions) => {
const {baseUrl, 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 = `${baseUrl.replace(/\/+$/, '')}/api/v1/projects/${encodeURIComponent(String(args.projectUuid))}/funnel/query${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(apiFunnelQueryResponse, await res.json())
};