epervier-old/birb/classes/predicate/init.lua
2021-12-04 13:18:54 +01:00

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No EOL
3.5 KiB
Lua

-- classes/predicates :: a predicate system, to be an intermediary between condition
-- solvers and complex conditions. You simply create a predicate with your data and the
-- solver to create a predicate, then use the Predicate:solve() API to get your response
-- To create a Predicate, prefer the Predicate.createPredicate instead of Predicate:new()
-- As it'll allow you to dynamically create simple or complex predicate on the fly
-- while Predicate:new() will try to create a complex predicate
--[[
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 Predicate = Object:extend()
local SimplePredicate = require "birb.classes.predicate.simple"
function Predicate.createPredicate(data, solver, asker)
local predicate = nil
if (type(data) == "table") then
predicate = Predicate(data, solver, asker)
end
if (type(data) == "string") then
predicate = SimplePredicate(data, solver, asker)
end
if (predicate ~= nil) then
return predicate
else
error("Predicate data aren't a table or a string : " .. tostring(data))
end
end
function Predicate:new(data ,solver, asker)
self.solver = solver
self.asker = asker
self.beginAt = 1
self:setType(data)
self.notTag = false
self:setList(data)
end
function Predicate:solve()
local predicateSolved
if (self.type == "or") then
predicateSolved = self:solveOr()
else
predicateSolved = self:solveAnd()
end
if (self.notTag) then
predicateSolved = (predicateSolved == false)
end
return predicateSolved
end
-- INTERNAL FUNCTIONS
-- Handle the complex predicate
function Predicate:setType(data)
self.type = "and"
if (type(data[1]) == "string") then
if (data[1] == "or") or (data[1] == "and") then
self.beginAt = 2
self.type = data[1]
end
end
end
function Predicate:setList(data)
self.list = {}
for i = self.beginAt, #data, 1 do
if (i == #data) and (data[i] == "not") then
self.notTag = true
else
table.insert(self.list, Predicate.createPredicate(data[i], self.solver, self.asker))
end
end
end
function Predicate:solveOr()
for i, predicate in ipairs(self.list) do
if (predicate:solve()) then
return true
end
end
return false
end
function Predicate:solveAnd()
for i, predicate in ipairs(self.list) do
if (not predicate:solve()) then
return false
end
end
return true
end
return Predicate