import {z} from 'zod'

export type GetApiFunnelsArgs = {project_id: number, workspace_id?: number | undefined, funnel_id: number, from_date: string, to_date: string, length?: number | undefined, length_unit?: ('day' | 'hour' | 'minute' | 'second') | undefined, interval?: number | undefined, unit?: ('day' | 'week' | 'month') | undefined, on?: string | undefined, where?: string | undefined, limit?: number | undefined};

export type GetApiFunnelsOptions = {baseUrl?: string | undefined, ServiceAccount?: {username: string, password: string} | undefined, fetch?: typeof fetch | undefined};

export const getApiFunnelsResponse = z.object({meta: z.object({dates: z.array(z.string()).optional()}).optional(), data: z.record(z.string(), z.object({steps: z.array(z.object({count: z.number().int().optional(), goal: z.string().optional(), step_conv_ratio: z.number().optional(), overall_conv_ratio: z.number().optional(), avg_time: z.number().int().optional(), avg_time_from_start: z.number().int().optional(), event: z.string().optional(), step_label: z.string().optional(), custom_event: z.boolean().optional(), custom_event_id: z.number().int().optional()})).optional(), analysis: z.object({completion: z.number().int().optional(), starting_amount: z.number().int().optional(), steps: z.number().int().optional(), worst: z.number().int().optional()}).optional()})).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
};

/**
 * Query Saved Report
 * 
 * GET /funnels
 * 
 * Also accepts auth: ProjectSecret
 */
export const getApiFunnels = async (args: GetApiFunnelsArgs, options?: GetApiFunnelsOptions) => {
const {baseUrl = "https://mixpanel.com/api/query", fetch: fetchFn = fetch, ServiceAccount} = options ?? {}

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

if (args.project_id != null) query.append("project_id", String(args.project_id))
if (args.workspace_id != null) query.append("workspace_id", String(args.workspace_id))
if (args.funnel_id != null) query.append("funnel_id", String(args.funnel_id))
if (args.from_date != null) query.append("from_date", String(args.from_date))
if (args.to_date != null) query.append("to_date", String(args.to_date))
if (args.length != null) query.append("length", String(args.length))
if (args.length_unit != null) query.append("length_unit", String(args.length_unit))
if (args.interval != null) query.append("interval", String(args.interval))
if (args.unit != null) query.append("unit", String(args.unit))
if (args.on != null) query.append("on", String(args.on))
if (args.where != null) query.append("where", String(args.where))
if (args.limit != null) query.append("limit", String(args.limit))
if (ServiceAccount !== undefined) headers.set('authorization', `Basic ${btoa(`${ServiceAccount.username}:${ServiceAccount.password}`)}`)

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