1 files changed, 79 insertions, 0 deletions
diff --git a/script/vm/visible.lua b/script/vm/visible.lua
new file mode 100644
index 00000000..ec538f24
--- /dev/null
+++ b/script/vm/visible.lua
@@ -0,0 +1,79 @@
+---@class vm
+local vm       = require 'vm.vm'
+local guide    = require 'parser.guide'
+
+---@param source parser.object
+---@return 'public' | 'protected' | 'private'
+function vm.getVisibleType(source)
+    if source.type == 'doc.field' then
+        return source.visible or 'public'
+    end
+    return 'public'
+end
+
+---@param source parser.object
+---@return vm.global?
+function vm.getParentClass(source)
+    if source.type == 'doc.field' then
+        return vm.getGlobalNode(source.class)
+    end
+    return nil
+end
+
+---@param suri uri
+---@param source parser.object
+---@return vm.global?
+function vm.getDefinedClass(suri, source)
+    local sets = vm.getLocalSourcesSets(source)
+    if sets then
+        for _, set in ipairs(sets) do
+            if set.bindDocs then
+                for _, doc in ipairs(set.bindDocs) do
+                    if doc.type == 'doc.class' then
+                        return vm.getGlobalNode(doc)
+                    end
+                end
+            end
+        end
+    end
+    local global = vm.getGlobalNode(source)
+    if global then
+        for _, set in ipairs(global:getSets(suri)) do
+            if set.bindDocs then
+                for _, doc in ipairs(set.bindDocs) do
+                    if doc.type == 'doc.class' then
+                        return vm.getGlobalNode(doc)
+                    end
+                end
+            end
+        end
+    end
+    return nil
+end
+
+---@param parent parser.object
+---@param field parser.object
+function vm.isVisible(parent, field)
+    local visible = vm.getVisibleType(field)
+    if visible == 'public' then
+        return true
+    end
+    local class = vm.getParentClass(field)
+    if not class then
+        return true
+    end
+    local suri = guide.getUri(parent)
+    local myClass = vm.getDefinedClass(suri, parent)
+    if not myClass then
+        return false
+    end
+    if myClass == class then
+        return true
+    end
+    if visible == 'protected' then
+        if vm.isSubType(suri, myClass, class) then
+            return true
+        end
+    end
+    return false
+end