local Luan = require "luan:Luan.luan"
local error = Luan.error
local ipairs = Luan.ipairs or error()
local pairs = Luan.pairs or error()
local stringify = Luan.stringify or error()
local Parsers = require "luan:Parsers.luan"
local json_parse = Parsers.json_parse or error()
local Shared = require "site:/lib/Shared.luan"
local user_error = Shared.user_error or error()
local After = require "site:/lib/After.luan"
local users = require "site:/private/lib/users.luan"
local shippers = require "site:/lib/shippers/shippers.luan"
local Order = require "site:/lib/Order.luan"


local Api = {}

local function check(request)
	local user = request.user or user_error "missing 'user'"
	local password = request.password or user_error "missing 'password'"
	local target = request.target or user_error "missing 'target'"
	target=="test" or target=="production" or user_error "target must be 'test' or 'production'"
	local user_info = users[user]
	if user_info == nil then
		target=="test" or user_error "invalid user"
	else
		password == user_info.password or user_error "invalid password"
	end
end

function Api.respond(request)
	check(request)
	local action = request.action or user_error "missing 'action'"
	local orders = request.orders or user_error "missing 'orders'"
	local rtn_orders = {}
	local shipper_requests = {}
	local check_keys = request.checkKeys==true
	for key, order in pairs(orders) do
		local shipper = order.shipper
		if shipper == nil then
			rtn_orders[key] = { okay=false, error="missing 'shipper'" }
			continue
		end
		if shippers[shipper] == nil then
			rtn_orders[key] = { okay=false, error="invalid shipper '"..shipper.."'" }
			continue
		end
		if shippers[shipper][action] == nil then
			rtn_orders[key] = { okay=false, error="shipper '"..shipper.."' doesn't support action '"..action.."'" }
			continue
		end
		if check_keys then
			local order_id = order.orderId
			if order_id == nil then
				rtn_orders[key] = { okay=false, error="checkKeys set but no orderId" }
				continue
			end
			local order = Order.get(shipper,order_id)
			if order ~= nil then
				local req = json_parse(order.request)
				local req_key = pairs(req.orders)() or error()
				if key ~= req_key then
					rtn_orders[key] = { okay=false, error="checkKeys failed, keys don't match, expected '"..req_key.."'" }
					continue
				end
			end
		end
		shipper_requests[shipper] = shipper_requests[shipper] or {}
		shipper_requests[shipper][key] = order
		--order.shipper = nil
	end
	for shipper, orders in pairs(shipper_requests) do
		local response_orders = shippers[shipper][action](request,orders)
		for key, order in pairs(response_orders) do
			if not order.okay and order.error==nil then
				error("invalid response "..stringify(order).."\nto "..action.." "..stringify(orders[key]))
			end
			rtn_orders[key] = order
		end
	end
	After[action] and After[action](request,rtn_orders)
	return {
		okay = true
		orders = rtn_orders
	}
end

return Api