epervier-old/framework/classes/predicate/simple.lua

68 lines
2.8 KiB
Lua

-- classes/simple :: the actual solver of the predicate system. It parse a condition
-- system, and pass the data to a solver function. If the last argument of a condition
-- is "not", it'll negate the whole condition.
-- Each solver function will get as argument the list of conditions, the predicate and the
-- asker. The predicate contain an utility subclass with some function to handle easily
-- some stuff like converting truth tags or comparing numbers
-- An empty string will return true, a non-existing solver question an error, except if the solver have a
-- default function.
--[[
Copyright © 2021 Kazhnuz
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
]]
local SimplePredicate = Object:extend()
local SEPARATOR = ":"
local NOT = "not"
local DEFAULT = "default"
SimplePredicate.utils = require "framework.classes.predicate.utils"
function SimplePredicate:new(data, solver, asker)
self.solver = solver
self.asker = asker
self.data = data
end
function SimplePredicate:solve()
if (utils.string.isEmpty(self.data)) then
return true
end
local conditionArgs = utils.string.split(self.data, SEPARATOR)
local solverFunction = self:getFunction(conditionArgs[1])
local conditionFulfilled = solverFunction(conditionArgs, self, self.asker)
if (conditionArgs[#conditionArgs] == NOT) then
conditionFulfilled = (not conditionFulfilled)
end
return conditionFulfilled
end
function SimplePredicate:getFunction(functionName)
if (self.solver[functionName] == nil) then
if (self.solver[DEFAULT] == nil) then
error("Function " .. functionName .. " doesn't exist in solver, and it doesn't have a 'default' function.")
end
return self.solver[DEFAULT]
end
return self.solver[functionName]
end
return SimplePredicate