const INVITE_CONTEXT_KEY = 'inviteShareContext'
const INVITE_DEVICE_KEY = 'inviteDeviceId'

function isBlank(value) {
	return value === undefined || value === null || String(value).trim() === ''
}

function readCurrentRegionId() {
	try {
		const area = uni.getStorageSync('area')
		if (!area) return ''
		const data = typeof area === 'string' ? JSON.parse(area) : area
		return data && data.id ? String(data.id) : ''
	} catch (e) {
		return ''
	}
}

function appendParam(query, key, value) {
	if (isBlank(value)) return
	query.push(key + '=' + encodeURIComponent(String(value)))
}

export function getInviteDeviceId() {
	let deviceId = ''
	try {
		deviceId = uni.getStorageSync(INVITE_DEVICE_KEY) || ''
	} catch (e) {}
	if (deviceId) return deviceId
	deviceId = 'dev_' + Date.now() + '_' + Math.random().toString(36).slice(2, 12)
	try {
		uni.setStorageSync(INVITE_DEVICE_KEY, deviceId)
	} catch (e) {}
	return deviceId
}

export function getCurrentInviteParams() {
	return {
		inviterId: uni.getStorageSync('id') || '',
		regionId: readCurrentRegionId()
	}
}

export function normalizeInviteParams(params) {
	params = params || {}
	const inviterId = params.inviterId || params.inviteUserId || ''
	const regionId = params.regionId || params.inviteRegionId || ''
	return {
		inviterId: isBlank(inviterId) ? '' : String(inviterId),
		regionId: isBlank(regionId) ? '' : String(regionId)
	}
}

function resolveInviteParams(params, useCurrentFallback) {
	const invite = normalizeInviteParams(params)
	if ((!invite.inviterId || !invite.regionId) && useCurrentFallback) {
		const current = getCurrentInviteParams()
		if (!invite.inviterId) invite.inviterId = current.inviterId
		if (!invite.regionId) invite.regionId = current.regionId
	}
	return invite
}

function appendInviteParams(query, params, useCurrentFallback) {
	const invite = resolveInviteParams(params, useCurrentFallback)
	appendParam(query, 'inviterId', invite.inviterId)
	appendParam(query, 'regionId', invite.regionId)
}

export function rememberInviteParams(params) {
	const invite = normalizeInviteParams(params)
	if (!invite.inviterId || !invite.regionId) return invite
	try {
		uni.setStorageSync(INVITE_CONTEXT_KEY, invite)
	} catch (e) {}
	return invite
}

export function getStoredInviteParams() {
	try {
		const stored = uni.getStorageSync(INVITE_CONTEXT_KEY)
		if (!stored) return { inviterId: '', regionId: '' }
		return normalizeInviteParams(typeof stored === 'string' ? JSON.parse(stored) : stored)
	} catch (e) {
		return { inviterId: '', regionId: '' }
	}
}

export function parseQueryString(queryString) {
	const result = {}
	String(queryString || '').split('&').forEach((item) => {
		if (!item) return
		const pair = item.split('=')
		const key = pair[0]
		if (!key) return
		const value = pair.slice(1).join('=')
		try {
			result[key] = decodeURIComponent(value || '')
		} catch (e) {
			result[key] = value || ''
		}
	})
	return result
}

export function extractInviteParamsFromUrl(url) {
	const value = String(url || '')
	const queryIndex = value.indexOf('?')
	if (queryIndex === -1) return { inviterId: '', regionId: '' }
	return normalizeInviteParams(parseQueryString(value.slice(queryIndex + 1)))
}

export function buildInviteHomeSharePath(params) {
	params = params || {}
	const query = ['shareType=invite']
	if (!isBlank(params.tabIndex)) {
		appendParam(query, 'tabIndex', params.tabIndex)
	}
	appendInviteParams(query, params, true)
	return '/pages/index/index?' + query.join('&')
}

export function buildHomeSharePath(targetPath, params) {
	const inviteQuery = []
	appendInviteParams(inviteQuery, params || {}, true)
	if (!targetPath) {
		return inviteQuery.length > 0 ? '/pages/index/index?' + inviteQuery.join('&') : '/pages/index/index'
	}
	let finalTargetPath = targetPath
	if (inviteQuery.length > 0) {
		finalTargetPath += (finalTargetPath.indexOf('?') === -1 ? '?' : '&') + inviteQuery.join('&')
	}
	return '/pages/index/index?targetPath=' + encodeURIComponent(finalTargetPath)
}

export function buildGroupHomeSharePath(params) {
	params = params || {}
	const query = [
		'shareType=group',
		'type=shop',
		'shopId=' + encodeURIComponent(params.shopId || ''),
		'groupId=' + encodeURIComponent(params.groupId || ''),
		'targetMembers=' + encodeURIComponent(params.targetMembers || 2),
		'isFaceToFace=' + encodeURIComponent(params.isFaceToFace || 0)
	]
	if (params.orderScene) {
		query.push('orderScene=' + encodeURIComponent(params.orderScene))
	}
	appendInviteParams(query, params, true)
	return '/pages/index/index?' + query.join('&')
}

export function buildGroupTargetPath(params) {
	params = params || {}
	if (!params.shopId || !params.groupId) return ''
	let targetPath = '/package2/group/groupBuySingle?type=shop' +
		'&shopId=' + encodeURIComponent(params.shopId) +
		'&groupId=' + encodeURIComponent(params.groupId) +
		'&targetMembers=' + encodeURIComponent(params.targetMembers || 2) +
		'&isFaceToFace=' + encodeURIComponent(params.isFaceToFace || 0)
	if (params.orderScene) {
		targetPath += '&orderScene=' + encodeURIComponent(params.orderScene)
	}
	const inviteQuery = []
	appendInviteParams(inviteQuery, params, false)
	if (inviteQuery.length > 0) {
		targetPath += '&' + inviteQuery.join('&')
	}
	return targetPath
}

export function buildGroupShopTargetPath(shopId) {
	if (!shopId) return ''
	return '/package2/group/groupBuySingle?type=shop&shopId=' + encodeURIComponent(shopId)
}

export function resolveMiniCodeSceneTarget(scene) {
	let value = String(scene || '').trim()
	if (!value) return ''
	try {
		value = decodeURIComponent(value)
	} catch (e) {}
	if (!value) return ''
	if (value.indexOf('groupShop:') === 0) {
		return buildGroupShopTargetPath(value.replace('groupShop:', ''))
	}
	if (/^s[A-Za-z0-9_-]{1,31}$/.test(value)) {
		return buildGroupShopTargetPath(value.slice(1))
	}
	return ''
}

export function normalizeShareTargetPath(value) {
	let targetPath = String(value || '')
	if (targetPath.indexOf('%2F') === 0 || targetPath.indexOf('%2f') === 0) {
		try {
			targetPath = decodeURIComponent(targetPath)
		} catch (e) {}
	}
	if (!targetPath || targetPath.charAt(0) !== '/') return ''
	if (targetPath.indexOf('/pages/index/index') === 0) return ''
	return targetPath
}

export function resolveHomeShareTarget(query) {
	query = query || {}
	rememberInviteParams(query)
	if (query.shareType === 'group') {
		return buildGroupTargetPath(query)
	}
	if (query.targetPath) {
		return normalizeShareTargetPath(query.targetPath)
	}
	return ''
}

export function isShareEnterScene(options) {
	if (!options || options.scene == null) return false
	const scene = Number(options.scene)
	return scene === 1007 || scene === 1008 || scene === 1044 || scene === 1154
}

export function getEnterShareTarget(options) {
	if (!options) {
		try {
			if (uni.getEnterOptionsSync) {
				options = uni.getEnterOptionsSync()
			} else if (uni.getLaunchOptionsSync) {
				options = uni.getLaunchOptionsSync()
			}
		} catch (e) {}
	}
	if (!isShareEnterScene(options)) return ''
	return resolveHomeShareTarget(options && options.query)
}

// 同一次分享进入只跳转一次。小程序切回前台、关闭图片预览都会再次触发 onShow，
// 且 App.onShow 仍可能带上最初的分享参数。
const handledShareTargets = Object.create(null)

export function stageShareEnter(options) {
	rememberInviteParams(options && options.query)
	const targetPath = resolveMiniCodeSceneTarget(options && options.query && options.query.scene) || getEnterShareTarget(options)
	if (!targetPath) return { targetPath: '', alreadyHandled: false }
	if (handledShareTargets[targetPath]) return { targetPath: '', alreadyHandled: true }
	return { targetPath: targetPath, alreadyHandled: false }
}

export function isShareTargetHandled(targetPath) {
	return !!(targetPath && handledShareTargets[targetPath])
}

export function completeShareEnter(targetPath) {
	if (targetPath) handledShareTargets[targetPath] = true
}

export function reopenShareEnter(targetPath) {
	if (targetPath) delete handledShareTargets[targetPath]
}

let suppressShareRedirectOnce = false

export function suppressNextShareRedirect() {
	suppressShareRedirectOnce = true
}

export function consumeShareRedirectSuppression() {
	if (!suppressShareRedirectOnce) return false
	suppressShareRedirectOnce = false
	return true
}

export function getCurrentEnterShareTarget() {
	let options = null
	try {
		if (uni.getEnterOptionsSync) {
			options = uni.getEnterOptionsSync()
		} else if (uni.getLaunchOptionsSync) {
			options = uni.getLaunchOptionsSync()
		}
	} catch (e) {}
	return getEnterShareTarget(options)
}