local Luan = require "luan:Luan.luan"
local error = Luan.error
local type = Luan.type or error()
local new_error = Luan.new_error or error()
local set_metatable = Luan.set_metatable or error()
local ipairs = Luan.ipairs or error()
local pairs = Luan.pairs or error()
local Table = require "luan:Table.luan"
local table_size = Table.size or error()
local Number = require "luan:Number.luan"
local integer = Number.integer or error()
local Io = require "luan:Io.luan"
local uri = Io.uri or error()
local Http = require "luan:http/Http.luan"
local Logging = require "luan:logging/Logging.luan"
local logger = Logging.logger "Shared"


local Shared = {}

Shared.is_production = Http.domain == "api.openshipper.com"

Shared.time_format = "yyyy-MM-dd HH:mm:ss"

local base_url = (Shared.is_production and "https" or "http").."://"..(Http.domain or "localhost:8080")
Shared.base_url = base_url 

local function user_error(msg)
	local e = new_error(msg)
	e.error = {
		okay = false
		error = msg
	}
	e.throw()
end
Shared.user_error = user_error

function Shared.handle_error(fn)
	return function(...)
		try
			return fn(...)
		catch e
			return e.error or e.throw()
		end
	end
end

function Shared.read_text(url,options)
	try
		return uri(url,options).read_text()
	catch e
		local msg = e.get_message()
		if msg=="Read timed out" or msg=="connect timed out" then
			logger.info(e)
			user_error(msg)
		end
		e.throw()
	end
end


local set_mt = {}
function set_mt.__index(table,key)
	return false
end

function Shared.list_to_set(list)
	local set = {}
	for _, v in ipairs(list) do
		set[v] = true
	end
	set_metatable(set,set_mt)
	return set
end

local function is_list(tbl)
	return #tbl == table_size(tbl)
end

function Shared.to_list(input)
	if input == nil then
		return {}
	elseif type(input) == "table" and is_list(input) then
		return input
	else
		return {input}
	end
end


local function in_what(what)
	return what and " in '"..what.name.."'"..in_what(what.parent) or ""
end

local function transform_flat(fields,flat,parent)
	--print("transform_flat")
	for field_name, field in pairs(fields) do
		if field.required then
			flat[field_name] or user_error("missing required field '"..field_name.."'"..in_what(parent))
		end
	end

	for key, value in pairs(flat) do
		local field = fields[key] or user_error("invalid field '"..key.."'"..in_what(parent))
		local value_type = type(value)
		local field_type = field.type
		local name = field.name or key
		value_type==field_type or user_error("field '"..key.."'"..in_what(parent).." must be type "..field_type)
		parent[name] = value
	end

	return parent

end

local function transform_map(fields,map,parent)
	for field_name, field in pairs(fields) do
		if field.required then
			map[field_name] or user_error("missing required field '"..field_name.."'"..in_what(parent))
		end
	end
	local rtn = {}
	for key, value in pairs(map) do
		local field = fields[key]
		if field == nil then
			continue  -- ignore unrecognized fields
		end
		local field_type = field.type
		local value_type = type(value)
		local name = field.name or key
		if field_type == "map" then
			value_type=="table" and #value==0 or user_error("field '"..key.."'"..in_what(parent).." must be type object")
			rtn[name] = transform_map( field.child, value, {name=key,parent=parent} )
		elseif field_type == "flat" then
			--print("transform_map flat type")
			rtn = transform_flat( field.child, value, rtn)
		elseif field_type == "list" then
			value_type=="table" and is_list(value) or user_error("field '"..key.."'"..in_what(parent).." must be type array")
			local children = field.children
			local this = {name=key,parent=parent}
			local list = {}
			for _, entry in ipairs(value) do
				list[#list+1] = transform_map(children,entry,this)
			end
			rtn[name] = list
		elseif field_type == "integer" then
			value_type=="number" or user_error("field '"..key.."'"..in_what(parent).." must be an integer")
			try
				rtn[name] = integer(value)
			catch e
				user_error("field '"..key.."'"..in_what(parent).." must be an integer")
			end
		else
			value_type==field_type or user_error("field '"..key.."'"..in_what(parent).." must be type "..field_type)
			rtn[name] = value
		end
	end
	return rtn
end
Shared.transform_map = transform_map


return Shared