import { storage } from "../lib/storage"

const MAX_HISTORY = 100

const instanceHistories = new Map<string, string[]>()
const historyLoaded = new Set<string>()

export async function addToHistory(instanceId: string, text: string): Promise<void> {
  await ensureHistoryLoaded(instanceId)

  const history = instanceHistories.get(instanceId) || []

  history.unshift(text)

  if (history.length > MAX_HISTORY) {
    history.length = MAX_HISTORY
  }

  instanceHistories.set(instanceId, history)

  try {
    await storage.saveInstanceData(instanceId, { messageHistory: history })
  } catch (err) {
    console.warn("Failed to persist message history:", err)
  }
}

export async function getHistory(instanceId: string): Promise<string[]> {
  await ensureHistoryLoaded(instanceId)
  return instanceHistories.get(instanceId) || []
}

export async function clearHistory(instanceId: string): Promise<void> {
  instanceHistories.delete(instanceId)
  historyLoaded.delete(instanceId)

  try {
    await storage.saveInstanceData(instanceId, { messageHistory: [] })
  } catch (error) {
    console.warn("Failed to clear history:", error)
  }
}

async function ensureHistoryLoaded(instanceId: string): Promise<void> {
  if (historyLoaded.has(instanceId)) {
    return
  }

  try {
    const data = await storage.loadInstanceData(instanceId)
    const history = Array.isArray(data.messageHistory) ? data.messageHistory : []
    instanceHistories.set(instanceId, history)
    historyLoaded.add(instanceId)
  } catch (error) {
    console.warn("Failed to load history:", error)
    instanceHistories.set(instanceId, [])
    historyLoaded.add(instanceId)
  }
}