import { reactive } from 'vue'

const STORAGE_KEY = 'overseas-pda-fulfillment-draft-v2'

const blankState = () => ({
	scopeKey: '',
	dispatch: { currentNo: '', palletCode: '', dispatchItemId: '', sourceKey: '', cartonCode: '', packages: 1 },
	outbound: { currentTaskNo: '', scanCode: '', packages: 1 }
})

export const fulfillment = reactive(blankState())

function storageAvailable() {
	return typeof uni !== 'undefined' && typeof uni.setStorageSync === 'function' && typeof uni.getStorageSync === 'function'
}

function safeDomain(value, fallback) { return Object.fromEntries(Object.keys(fallback).map(key => [key, value?.[key] ?? fallback[key]])) }

export function persistFulfillmentDraft() {
	if (!storageAvailable() || !fulfillment.scopeKey) return
	uni.setStorageSync(STORAGE_KEY, JSON.parse(JSON.stringify(fulfillment)))
}

export function restoreFulfillmentDraft(scopeKey) {
	const expected = String(scopeKey || '')
	if (!expected) return false
	const saved = storageAvailable() ? uni.getStorageSync(STORAGE_KEY) : null
	if (!saved || saved.scopeKey !== expected) {
		Object.assign(fulfillment, blankState(), { scopeKey: expected })
		if (storageAvailable()) uni.removeStorageSync(STORAGE_KEY)
		return false
	}
	const fresh = blankState()
	Object.assign(fulfillment, fresh, {
		scopeKey: expected,
		dispatch: safeDomain(saved.dispatch, fresh.dispatch),
		outbound: safeDomain(saved.outbound, fresh.outbound)
	})
	return true
}

export function updateFulfillmentDraft(domain, patch) {
	if (!fulfillment[domain]) throw new Error('未知海外 PDA 履约草稿')
	Object.assign(fulfillment[domain], patch)
	persistFulfillmentDraft()
}

function randomKey(domain, action) {
	return `pda-${domain}-${action}-${Date.now()}-${Math.random().toString(36).slice(2, 10)}`
}

export function fulfillmentIdempotencyKey(domain, action, _payload = {}) {
    if (!fulfillment[domain]) throw new Error('未知海外 PDA 履约类型')
    return { value: randomKey(domain, action) }
}

export function resetFulfillmentDomain(domain) {
	if (!fulfillment[domain]) return
	fulfillment[domain] = blankState()[domain]
	persistFulfillmentDraft()
}

export function resetFulfillmentSession() {
	Object.assign(fulfillment, blankState())
	if (typeof uni !== 'undefined' && typeof uni.removeStorageSync === 'function') uni.removeStorageSync(STORAGE_KEY)
}