import { reactive } from 'vue'
import { resetPickingSession } from '@/stores/picking.js'
import { PLATFORM_API_ROOT } from '@/config/runtime.js'
import { decodeAccessToken } from '@/utils/jwt-claims.js'

export { decodeAccessToken } from '@/utils/jwt-claims.js'

let sessionRevision = 0
export function getSessionRevision() { return sessionRevision }

const SESSION_KEY = 'pda-auth-session'
const LOGIN_PREFERENCE_KEY = 'pda-login-account-preference'

export const session = reactive({ currentUser: null, token: '', refreshToken: '', tenantId: '', apiBase: PLATFORM_API_ROOT })

export function isDomesticPdaOperator(user = session.currentUser) {
	return Array.isArray(user?.roles) && user.roles.includes('CN_FIRSTLEG_PDA_OPERATOR')
}

export function isAccessTokenExpiring(token = session.token, skewSeconds = 30) {
	try {
		const expiresAt = Number(decodeAccessToken(token).exp || 0) * 1000
		return !expiresAt || expiresAt <= Date.now() + skewSeconds * 1000
	} catch (_) {
		return true
	}
}

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

export function loadLoginPreference() {
	if (!storageAvailable()) return { rememberAccount: true, account: '' }
	const saved = uni.getStorageSync(LOGIN_PREFERENCE_KEY)
	if (!saved || typeof saved !== 'object') return { rememberAccount: true, account: '' }
	return { rememberAccount: saved.rememberAccount !== false, account: String(saved.account || '') }
}

export function saveLoginPreference(rememberAccount, account = '') {
	if (!storageAvailable()) return
	uni.setStorageSync(LOGIN_PREFERENCE_KEY, {
		rememberAccount: Boolean(rememberAccount),
		account: rememberAccount ? String(account || '').trim() : ''
	})
}

function persistSession() {
	if (!storageAvailable()) return
	uni.setStorageSync(SESSION_KEY, {
		currentUser: session.currentUser,
		token: session.token,
		refreshToken: session.refreshToken,
		tenantId: session.tenantId
	})
}

export function signIn(account, warehouse, options = {}) {
	sessionRevision++
	session.currentUser = { id: String(account.id), name: account.name, role: account.role, roles: account.roles || [], warehouse, warehouseId: account.warehouseId || null, domesticWarehouseId: account.domesticWarehouseId || null, warehouseBound: Boolean(account.domesticWarehouseId) }
	session.token = options.token || account.token || ''
	session.refreshToken = options.refreshToken || account.refreshToken || ''
	session.tenantId = options.tenantId || account.tenantId || ''
	// The endpoint belongs to the installed build, not to a persisted login.
	// Otherwise changing environments leaves existing devices on the old API.
	session.apiBase = PLATFORM_API_ROOT
	persistSession()
	return session.currentUser
}

export function signInWithTokens(tokens) {
	if (!tokens?.accessToken) throw new Error('登录响应缺少 accessToken')
	if (!tokens?.refreshToken) throw new Error('登录响应缺少 refreshToken')
	const claims = decodeAccessToken(tokens.accessToken)
	if (claims.app_code !== 'PLATFORM') throw new Error('当前账号不属于平台作业端')
	if (claims.exp && claims.exp * 1000 <= Date.now()) throw new Error('登录状态已过期')
	return signIn({
		id: claims.user_id ?? '',
		name: claims.username || '仓库作业员',
		role: Array.isArray(claims.roles || tokens.roles) ? (claims.roles || tokens.roles).join('、') : '',
		roles: claims.roles || tokens.roles || [],
		domesticWarehouseId: claims.domestic_warehouse_id || tokens.domesticWarehouseId || null
	}, '', {
		token: tokens.accessToken,
		refreshToken: tokens.refreshToken || '',
		tenantId: claims.tenant_id == null ? '' : String(claims.tenant_id)
	})
}

export function selectWarehouse(warehouse) {
	if (!session.currentUser) throw new Error('请先登录')
	if (!warehouse?.id || !warehouse?.warehouseName) throw new Error('请选择有效的作业仓库')
	const warehouseId = String(warehouse.id)
	if (isDomesticPdaOperator() && String(session.currentUser.domesticWarehouseId || '') !== warehouseId) throw new Error('当前账号已绑定固定作业仓库，不能切换')
	if (String(session.currentUser.warehouseId || '') !== warehouseId) resetPickingSession()
	session.currentUser = {
		...session.currentUser,
		warehouseId,
		warehouse: String(warehouse.warehouseName),
		warehouseCode: String(warehouse.warehouseCode || '')
	}
	persistSession()
	return session.currentUser
}

export function updateTokenPair(tokens) {
	if (!tokens?.accessToken) throw new Error('刷新响应缺少 accessToken')
	if (!tokens?.refreshToken) throw new Error('刷新响应缺少 refreshToken')
	const claims = decodeAccessToken(tokens.accessToken)
	if (claims.app_code !== 'PLATFORM') throw new Error('当前账号不属于平台作业端')
	if (claims.exp && claims.exp * 1000 <= Date.now()) throw new Error('刷新后的登录状态已过期')
	const previousUser = session.currentUser || {}
	session.currentUser = {
		...previousUser,
		id: String(claims.user_id ?? previousUser.id ?? ''),
		name: claims.username || previousUser.name || '仓库作业员',
		role: Array.isArray(claims.roles) ? claims.roles.join('、') : (previousUser.role || ''),
		roles: claims.roles || previousUser.roles || [],
		domesticWarehouseId: claims.domestic_warehouse_id || previousUser.domesticWarehouseId || null,
		warehouseBound: Boolean(claims.domestic_warehouse_id || previousUser.domesticWarehouseId)
	}
	session.token = tokens.accessToken
	session.refreshToken = tokens.refreshToken
	session.tenantId = claims.tenant_id == null ? session.tenantId : String(claims.tenant_id)
	persistSession()
	return session.token
}

export function restoreSession() {
	if (!storageAvailable()) return false
	const saved = uni.getStorageSync(SESSION_KEY)
	if (!saved?.token || !saved?.currentUser) return false
	try {
		const claims = decodeAccessToken(saved.token)
		if (claims.app_code !== 'PLATFORM') throw new Error('登录域无效')
		if (claims.exp && claims.exp * 1000 <= Date.now() && !saved.refreshToken) throw new Error('登录状态已过期')
		const savedUser = saved.currentUser || {}
		Object.assign(session, saved, {
			currentUser: {
				...savedUser,
				id: String(claims.user_id ?? savedUser.id ?? ''),
				name: claims.username || savedUser.name || '仓库作业员',
				role: Array.isArray(claims.roles) ? claims.roles.join('、') : (savedUser.role || ''),
				roles: claims.roles || savedUser.roles || [],
				domesticWarehouseId: claims.domestic_warehouse_id || savedUser.domesticWarehouseId || null,
				warehouseBound: Boolean(claims.domestic_warehouse_id || savedUser.domesticWarehouseId)
			},
			tenantId: claims.tenant_id == null ? (saved.tenantId || '') : String(claims.tenant_id),
			apiBase: saved.apiBase || PLATFORM_API_ROOT
		})
		sessionRevision++
		persistSession()
		return true
	} catch (_) {
		signOut()
		return false
	}
}

export function signOut() {
	sessionRevision++
	session.currentUser = null
	session.token = ''
	session.refreshToken = ''
	session.tenantId = ''
	session.apiBase = PLATFORM_API_ROOT
	if (typeof uni !== 'undefined' && typeof uni.removeStorageSync === 'function') uni.removeStorageSync(SESSION_KEY)
	resetPickingSession()
}

export function requireSession() {
	if (session.currentUser || restoreSession()) return true
	uni.reLaunch({ url: '/pages/login/login' })
	return false
}