1 files changed, 132 insertions, 0 deletions
diff --git a/script/vm/global-id.lua b/script/vm/global-id.lua
new file mode 100644
index 00000000..614e28c5
--- /dev/null
+++ b/script/vm/global-id.lua
@@ -0,0 +1,132 @@
+local util          = require 'utility'
+local guide         = require 'parser.guide'
+local globalBuilder = require 'vm.node.global'
+
+---@class parser.object
+---@field _globalID vm.node.global
+
+---@class vm.global-id
+local m = {}
+---@type table<string, vm.node.global>
+m.globals = util.defaultTable(globalBuilder)
+---@type table<uri, table<string, boolean>>
+m.globalSubs = util.defaultTable(function ()
+    return {}
+end)
+
+m.ID_SPLITE = '\x1F'
+
+local compilerGlobalMap = util.switch()
+    : case 'local'
+    : call(function (uri, source)
+        if source.tag ~= '_ENV' then
+            return
+        end
+        if source.ref then
+            for _, ref in ipairs(source.ref) do
+                m.compileNode(uri, ref)
+            end
+        end
+    end)
+    : case 'setglobal'
+    : call(function (uri, source)
+        local name = guide.getKeyName(source)
+        source._globalID = m.declareGlobal(name, uri, source)
+    end)
+    : case 'getglobal'
+    : call(function (uri, source)
+        local name   = guide.getKeyName(source)
+        local global = m.getGlobal(name)
+        global:addGet(uri, source)
+        source._globalID = global
+
+        local nxt = source.next
+        if nxt then
+            m.compileNode(uri, nxt)
+        end
+    end)
+    : case 'setfield'
+    ---@param uri    uri
+    ---@param source parser.object
+    : call(function (uri, source)
+        local parent = source.node._globalID
+        if not parent then
+            return
+        end
+        local name = parent:getName() .. m.ID_SPLITE .. guide.getKeyName(source)
+        source._globalID = m.declareGlobal(name, uri, source)
+    end)
+    : case 'getfield'
+    ---@param uri    uri
+    ---@param source parser.object
+    : call(function (uri, source)
+        local parent = source.node._globalID
+        if not parent then
+            return
+        end
+        local name = parent:getName() .. m.ID_SPLITE .. guide.getKeyName(source)
+        local global = m.getGlobal(name)
+        global:addGet(uri, source)
+        source._globalID = global
+
+        local nxt = source.next
+        if nxt then
+            m.compileNode(uri, nxt)
+        end
+    end)
+    : getMap()
+
+
+---@param name   string
+---@param uri    uri
+---@param source parser.object
+---@return vm.node.global
+function m.declareGlobal(name, uri, source)
+    m.globalSubs[uri][name] = true
+    local node = m.globals[name]
+    node:addSet(uri, source)
+    return node
+end
+
+---@param name string
+---@param uri? uri
+---@return vm.node.global
+function m.getGlobal(name, uri)
+    if uri then
+        m.globalSubs[uri][name] = true
+    end
+    return m.globals[name]
+end
+
+---@param source parser.object
+function m.compileNode(uri, source)
+    if source._globalID ~= nil then
+        return
+    end
+    source._globalID = false
+    local compiler = compilerGlobalMap[source.type]
+    if compiler then
+        compiler(uri, source)
+    end
+end
+
+---@param source parser.object
+function m.compileAst(source)
+    local uri = guide.getUri(source)
+    local env = guide.getENV(source)
+    m.compileNode(uri, env)
+end
+
+function m.getID(source)
+    return source._globalID
+end
+
+function m.dropUri(uri)
+    local globalSub = m.globalSubs[uri]
+    m.globalSubs[uri] = nil
+    for name in pairs(globalSub) do
+        m.globals[name]:dropUri(uri)
+    end
+end
+
+return m