// Availability is computed by the server; never infer presence from HTTP success.
import { supportCalendarPayload } from "@/lib/support-availability"
import { request } from "@/lib/api/client"
import type { ServiceStatus } from "@/lib/generated/enums"
import { readSupportChatRuntimeConfig } from "@/lib/sdk/runtime-config"

export type SupportPeriod = { start: string; end: string }
export type SupportCalendar = {
  teamId: number
  mode: "legacy" | "recurring"
  timezone: string
  effectiveTimezone: string
  deploymentTimezone: string
  weekly: (SupportPeriod & { weekday: number })[]
  exceptions: { date: string; closed: boolean; periods: SupportPeriod[] }[]
}
export type AvailabilityReason = "eligible" | "profile_disabled" | "user_disabled" | "team_disabled" | "outside_hours" | "offline" | "busy" | "break" | "unavailable" | "vacation" | "auto_assign_disabled" | "capacity"
export type OperatorAvailability = {
  userId: number
  profileId: number
  teamId: number
  displayName?: string
  serviceStatus: ServiceStatus
  effectiveServiceStatus: ServiceStatus
  returnServiceStatus?: ServiceStatus
  absenceStartAt?: string
  absenceEndAt?: string
  online: boolean
  eligible: boolean
  reason: AvailabilityReason
  calendar: SupportCalendar
  calendarOpen: boolean
  nextOpeningAt?: string
}
export type AvailabilityUpdate = { serviceStatus: ServiceStatus; absenceStartAt?: string; absenceEndAt?: string }
export type CalendarPreview = { open: boolean; timezone: string; nextOpeningAt?: string; mode: SupportCalendar["mode"] }
export type PublicSupportStatus = { available: boolean; reason: "available" | "outside_hours" | "temporarily_absent" | "capacity"; timezone: string; nextOpeningAt?: string }
const base = "/api/dashboard/support_availability"
// Bound background reads so one hung request cannot freeze polling forever.
async function availabilityRead<T>(path: string, options: Parameters<typeof request>[1] = {}) {
  const controller = new AbortController()
  const abort = () => controller.abort()
  const source = options.signal
  if (source?.aborted) controller.abort()
  else source?.addEventListener("abort", abort, { once: true })
  const deadline = setTimeout(abort, 10000)
  try { return await request<T>(path, { ...options, signal: controller.signal }) }
  finally { clearTimeout(deadline); source?.removeEventListener("abort", abort) }
}
export function fetchMyAvailability(signal?: AbortSignal) { return availabilityRead<OperatorAvailability | null>(`${base}/me`, { signal }) }
export function updateMyAvailability(payload: AvailabilityUpdate) { return request<OperatorAvailability>(`${base}/me`, { method: "POST", body: JSON.stringify(payload) }) }
export function fetchAvailabilityAgents(conversationId?: number, signal?: AbortSignal) { return availabilityRead<OperatorAvailability[]>(`${base}/agents${conversationId ? `?conversationId=${conversationId}` : ""}`, { signal }) }
export function updateAgentAvailability(userId: number, payload: AvailabilityUpdate) { return request<OperatorAvailability>(`${base}/agent`, { method: "POST", body: JSON.stringify({ ...payload, userId }) }) }
export async function fetchSupportCalendar(teamId: number) {
  const data = await availabilityRead<SupportCalendar>(`${base}/calendar?teamId=${teamId}`)
  return { ...data, weekly: data.weekly ?? [], exceptions: (data.exceptions ?? []).map(item => ({ ...item, periods: item.periods ?? [] })) }
}
export function updateSupportCalendar(calendar: SupportCalendar) { return request<SupportCalendar>(`${base}/calendar`, { method: "POST", body: JSON.stringify(supportCalendarPayload(calendar)) }) }
export function previewSupportCalendar(calendar: SupportCalendar, at?: string) { return availabilityRead<CalendarPreview>(`${base}/calendar/preview`, { method: "POST", body: JSON.stringify({ calendar: supportCalendarPayload(calendar), at }) }) }
export function fetchPublicSupportStatus(signal?: AbortSignal) {
  const config = readSupportChatRuntimeConfig()
  return availabilityRead<PublicSupportStatus>("/api/support/status", {
    skipAuth: true, signal,
    baseUrl: (config.apiBaseUrl || config.baseUrl || process.env.NEXT_PUBLIC_API_BASE_URL || "").trim().replace(/\/$/, ""),
    headers: { "X-Channel-Id": config.channelId || process.env.NEXT_PUBLIC_OPEN_IM_CHANNEL_ID?.trim() || "" },
  })
}