import { initialsFromDisplayName } from "./column-filter-range-policy"
import type { ColumnCellKind } from "./column-cell-kind"

export type PersonFilterOption = {
  value: string
  label: string
  initials?: string
  email?: string
}

function personFromStub(raw: unknown): PersonFilterOption | null {
  if (!raw || typeof raw !== "object" || !("name" in raw)) return null
  const record = raw as { name?: unknown; initials?: unknown }
  const name = String(record.name ?? "").trim()
  if (!name) return null
  const initials =
    typeof record.initials === "string"
      ? record.initials
      : initialsFromDisplayName(name)
  return { value: name, label: name, initials }
}

/** Unique person options for avatar pickers — derived from the hub dataset. */
export function derivePersonFilterOptions<T extends Record<string, unknown>>(
  rows: T[],
  fieldKey: string,
  cellKind?: ColumnCellKind,
): PersonFilterOption[] {
  const seen = new Map<string, PersonFilterOption>()
  const emailKey = `${fieldKey}Email`

  for (const row of rows) {
    const val = row[fieldKey]

    if (cellKind === "people-rail" && Array.isArray(val)) {
      for (const entry of val) {
        const opt = personFromStub(entry)
        if (opt && !seen.has(opt.value)) seen.set(opt.value, opt)
      }
      continue
    }

    if (typeof val === "string" && val.trim()) {
      if (seen.has(val)) continue
      const email =
        typeof row[emailKey] === "string" ? (row[emailKey] as string) : undefined
      seen.set(val, {
        value: val,
        label: val,
        initials: initialsFromDisplayName(val),
        email,
      })
    }
  }

  return [...seen.values()].sort((a, b) => a.label.localeCompare(b.label))
}

export function isPersonSelectFilter(cellKind?: ColumnCellKind): boolean {
  return cellKind === "person" || cellKind === "people-rail"
}