import {z} from 'zod'

export type MetricEvent = {id: string, occurred_at: string, session_id?: string | undefined, install_id?: string | undefined, harness?: string | undefined, provider?: string | undefined, model?: string | undefined, action_kind: 'unknown' | 'log' | 'test_build_lint' | 'search' | 'file_list' | 'document_read' | 'agent_handoff' | 'query' | 'verbatim', decision: string, reason?: string | undefined, original_bytes?: number | undefined, replacement_bytes?: number | undefined, provider_input_tokens?: number | undefined, provider_output_tokens?: number | undefined, provider_cache_read_tokens?: number | undefined, provider_cache_write_tokens?: number | undefined, estimated_cost_microusd?: number | undefined, reducer_cost_microusd?: number | undefined, elapsed_ms?: number | undefined, turn_count?: number | undefined, retry_count?: number | undefined, reread_count?: number | undefined, retrieval_count?: number | undefined, client_version?: string | undefined};

export type MetricsBatch = {events: Array<MetricEvent>};

export type CreateApiV1MetricsBatchArgs = {body: MetricsBatch};

export type CreateApiV1MetricsBatchOptions = {baseUrl: string, fetch?: typeof fetch | undefined};

export const createApiV1MetricsBatchResponse = z.record(z.string(), z.number().int());

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
};

/**
 * Record Metrics
 * 
 * POST /v1/metrics/batch
 */
export const createApiV1MetricsBatch = async (args: CreateApiV1MetricsBatchArgs, options: CreateApiV1MetricsBatchOptions) => {
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 = `${baseUrl.replace(/\/+$/, '')}/v1/metrics/batch${query.size > 0 ? `?${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(createApiV1MetricsBatchResponse, await res.json())
};