// Local user preferences — title, signature, default agent, plus a cache
// mirror of the resolved avatar URL. Persisted in localStorage; reactive
// across tabs. Identity (name, email) is owned by the arcadia session
// (~/lib/session.ts); the public profile (bio, phone, location, timezone)
// is server-backed via /api/v1/profile (~/lib/arcadia/profiles.ts).

import { useEffect, useSyncExternalStore } from "react"

export type Profile = {
  title: string
  signature: string
  avatarUrl: string
  defaultAgentId: string
}

export const DEFAULT_PROFILE: Profile = {
  title: "",
  signature: "",
  avatarUrl: "",
  defaultAgentId: "",
}

const STORAGE_KEY = "crema.profile"
const CHANGE_EVENT = "crema:profile-change"

function readFromStorage(): Profile {
  if (typeof window === "undefined") return DEFAULT_PROFILE
  try {
    const raw = localStorage.getItem(STORAGE_KEY)
    if (!raw) return DEFAULT_PROFILE
    const parsed = JSON.parse(raw) as Partial<Profile>
    return {
      title:
        typeof parsed.title === "string" ? parsed.title : DEFAULT_PROFILE.title,
      signature:
        typeof parsed.signature === "string"
          ? parsed.signature
          : DEFAULT_PROFILE.signature,
      avatarUrl:
        typeof parsed.avatarUrl === "string"
          ? parsed.avatarUrl
          : DEFAULT_PROFILE.avatarUrl,
      defaultAgentId:
        typeof parsed.defaultAgentId === "string"
          ? parsed.defaultAgentId
          : DEFAULT_PROFILE.defaultAgentId,
    }
  } catch {
    return DEFAULT_PROFILE
  }
}

export function loadProfile(): Profile {
  return readFromStorage()
}

export function saveProfile(next: Profile) {
  if (typeof window === "undefined") return
  localStorage.setItem(STORAGE_KEY, JSON.stringify(next))
  window.dispatchEvent(new CustomEvent(CHANGE_EVENT))
}

export function resetProfile() {
  saveProfile(DEFAULT_PROFILE)
}

export function profileInitials(name: string): string {
  const words = name.trim().split(/\s+/).filter(Boolean)
  if (words.length === 0) return "?"
  if (words.length === 1) return words[0].slice(0, 2).toUpperCase()
  return (words[0][0] + words[words.length - 1][0]).toUpperCase()
}

let cached: Profile | null = null

function subscribe(cb: () => void): () => void {
  const onChange = () => {
    cached = null
    cb()
  }
  window.addEventListener(CHANGE_EVENT, onChange)
  window.addEventListener("storage", (e) => {
    if (e.key === STORAGE_KEY) onChange()
  })
  return () => {
    window.removeEventListener(CHANGE_EVENT, onChange)
  }
}

function getSnapshot(): Profile {
  if (!cached) cached = readFromStorage()
  return cached
}

function getServerSnapshot(): Profile {
  return DEFAULT_PROFILE
}

export function useProfile(): Profile {
  const value = useSyncExternalStore(subscribe, getSnapshot, getServerSnapshot)
  useEffect(() => {
    cached = null
  }, [])
  return value
}