export type PendingTextIntent = {
  text: string;
  dialogKey: string;
  messageKey: string;
  dialogId?: string;
};

const STORAGE_KEY = "han.pending-message";
let pendingTextIntent: PendingTextIntent | null = null;
let pendingFileIntent: PendingFileIntent | null = null;

export type PendingFileIntent = {
  file: File;
  dialogKey: string;
  dialogId?: string;
  messageKey: string;
};

export function createPendingTextIntent(text: string): PendingTextIntent {
  return {
    text,
    dialogKey: crypto.randomUUID(),
    messageKey: crypto.randomUUID(),
  };
}

export function savePendingTextIntent(intent: PendingTextIntent) {
  pendingTextIntent = intent;
  if (typeof window !== "undefined") {
    window.sessionStorage.setItem(STORAGE_KEY, JSON.stringify(intent));
  }
}

export function loadPendingTextIntent(): PendingTextIntent | null {
  if (pendingTextIntent) return pendingTextIntent;
  if (typeof window === "undefined") return null;
  const raw = window.sessionStorage.getItem(STORAGE_KEY);
  if (!raw) return null;
  try {
    const value = JSON.parse(raw) as Partial<PendingTextIntent>;
    if (
      typeof value.text !== "string"
      || typeof value.dialogKey !== "string"
      || typeof value.messageKey !== "string"
    ) {
      return null;
    }
    pendingTextIntent = {
      text: value.text,
      dialogKey: value.dialogKey,
      messageKey: value.messageKey,
      ...(typeof value.dialogId === "string" ? { dialogId: value.dialogId } : {}),
    };
    return pendingTextIntent;
  } catch {
    return null;
  }
}

export function bindPendingTextIntent(intent: PendingTextIntent, dialogId: string) {
  const bound = { ...intent, dialogId };
  savePendingTextIntent(bound);
  return bound;
}

export function clearPendingTextIntent() {
  pendingTextIntent = null;
  if (typeof window !== "undefined") {
    window.sessionStorage.removeItem(STORAGE_KEY);
  }
}

export function savePendingFileIntent(intent: PendingFileIntent) {
  pendingFileIntent = intent;
}

export function bindPendingFileIntent(dialogId: string) {
  if (pendingFileIntent) pendingFileIntent = { ...pendingFileIntent, dialogId };
}

export function pendingDialogKey() {
  return loadPendingTextIntent()?.dialogKey ?? pendingFileIntent?.dialogKey;
}

export function loadPendingFileIntent(dialogId: string) {
  return pendingFileIntent?.dialogId === dialogId ? pendingFileIntent : null;
}

export function clearPendingFileIntent() {
  pendingFileIntent = null;
}