Added instances

expcore/Gui/instances.lua

@@ -0,0 +1,117 @@
+--- This file is a breakout from core which forcues on instance management of defines
+local Global = require 'utils.global'
+
+local Instances = {
+    categorise={},
+    data={}
+}
+Global.register(Instances.data,function(tbl)
+    Instances.data = tbl
+end)
+
+function Instances.has_categories(name)
+    return type(Instances.categorise[name]) == 'function'
+end
+
+function Instances.is_registered(name)
+    return Instances.categorise[name] ~= nil
+end
+
+function Instances.register(name,categorise)
+    if _LIFECYCLE ~= _STAGE.control then
+        return error('Can only be called during the control stage', 2)
+    end
+
+    if Instances.categorise[name] then
+        return error('Instances for '..name..' already exist.',2)
+    end
+
+    categorise = type(categorise) == 'function' and categorise or true
+
+    Instances.data[name] = {}
+    Instances.categorise[name] = categorise
+
+    return name
+end
+
+function Instances.add_element(name,element)
+    if not Instances.categorise[name] then
+        return error('Inavlid name for instance group: '..name,2)
+    end
+
+    if Instances.has_categories(name) then
+        local category = Instances.categorise[name](element)
+        if not Instances.data[name][category] then Instances.data[name][category] = {} end
+        table.insert(Instances.data[name][category],element)
+    else
+        table.insert(Instances.data[name],element)
+    end
+end
+
+function Instances.get_elements_raw(name,category)
+    if not Instances.categorise[name] then
+        return error('Inavlid name for instance group: '..name,2)
+    end
+
+    if Instances.has_categories(name) then
+        return Instances.data[name][category] or {}
+    else
+        return Instances.data[name]
+    end
+end
+
+function Instances.get_valid_elements(name,category,callback)
+    if not Instances.categorise[name] then
+        return error('Inavlid name for instance group: '..name,2)
+    end
+
+    category = category or callback
+    local elements = Instances.get_elements_raw(name,category)
+    local categorise = Instances.has_categories(name)
+
+    for key,element in pairs(elements) do
+        if not element or not element.valid then
+            elements[key] = nil
+        else
+            if categorise and callback then callback(element)
+            elseif category then category(element) end
+        end
+    end
+
+    return elements
+end
+Instances.get_elements = Instances.get_valid_elements
+Instances.apply_to_elements = Instances.get_valid_elements
+
+function Instances.unregistered_add_element(name,categorise,element)
+    if not Instances.data[name] then Instances.data[name] = {} end
+    if type(categorise) == 'function' then
+        local category = categorise(element)
+        if not Instances.data[name][category] then Instances.data[name][category] = {} end
+        table.insert(Instances.data[name][category],element)
+    else
+        table.insert(Instances.data[name],element)
+    end
+end
+
+function Instances.unregistered_get_elements(name,category,callback)
+    local elements = Instances.data[name]
+    if category then
+        elements = Instances.data[name][category]
+    end
+
+    if not elements then return {} end
+
+    for key,element in pairs(elements) do
+        if not element or not element.valid then
+            elements[key] = nil
+        else
+            if callback then callback(element) end
+        end
+    end
+
+    return elements
+end
+Instances.unregistered_apply_to_elements = Instances.runtime_get_elements
+
+return Instances