From df7f7ea8ab732289a130ca13631e3551f9a91dc5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ra=C3=BAl=20Ferr=C3=A0s?= <raulferras@gmail.com>
Date: Tue, 17 Sep 2024 19:27:00 +0200
Subject: [PATCH] WIP displaying type size on hover.

---
 .../internal/lsp/server/TextDocumentHover.go  | 89 ++++++++++++++++++-
 server/pkg/symbols/type.go                    |  4 +
 server/pkg/utils/arch.go                      | 31 +++++++
 server/pkg/utils/features.go                  | 17 ++++
 4 files changed, 140 insertions(+), 1 deletion(-)
 create mode 100644 server/pkg/utils/arch.go
 create mode 100644 server/pkg/utils/features.go

diff --git a/server/internal/lsp/server/TextDocumentHover.go b/server/internal/lsp/server/TextDocumentHover.go
index d8cdd18..fde8c3e 100644
--- a/server/internal/lsp/server/TextDocumentHover.go
+++ b/server/internal/lsp/server/TextDocumentHover.go
@@ -1,6 +1,8 @@
 package server
 
 import (
+	"fmt"
+
 	"github.com/pherrymason/c3-lsp/pkg/symbols"
 	"github.com/pherrymason/c3-lsp/pkg/utils"
 	"github.com/tliron/glsp"
@@ -30,13 +32,98 @@ func (h *Server) TextDocumentHover(context *glsp.Context, params *protocol.Hover
 		extraLine += "\n\nIn module **[" + foundSymbol.GetModuleString() + "]**"
 	}
 
+	sizeInfo := ""
+	if utils.IsFeatureEnabled("SIZE_ON_HOVER") {
+		if hasSize(foundSymbol) {
+			sizeInfo = "// size = " + calculateSize(foundSymbol) + ", align = " + calculateAlignment(foundSymbol) + "\n"
+		}
+	}
+
 	hover := protocol.Hover{
 		Contents: protocol.MarkupContent{
 			Kind: protocol.MarkupKindMarkdown,
-			Value: "```c3" + "\n" + foundSymbol.GetHoverInfo() + "\n```" +
+			Value: "```c3" + "\n" +
+				sizeInfo +
+				foundSymbol.GetHoverInfo() + "\n```" +
 				extraLine,
 		},
 	}
 
 	return &hover, nil
 }
+
+func hasSize(symbol symbols.Indexable) bool {
+	_, isVariable := symbol.(*symbols.Variable)
+	if isVariable {
+		return true
+	}
+
+	_, isMember := symbol.(*symbols.StructMember)
+	if isMember {
+		return true
+	}
+
+	_, isStruct := symbol.(*symbols.Struct)
+	if isStruct {
+		return true
+	}
+
+	_, isBitStruct := symbol.(*symbols.Bitstruct)
+	if isBitStruct {
+		return true
+	}
+
+	return false
+}
+
+func calculateSize(symbol symbols.Indexable) string {
+	variable, isVariable := symbol.(*symbols.Variable)
+	if isVariable {
+		if variable.Type.IsPointer() {
+			return fmt.Sprintf("%d", utils.PointerSize())
+		}
+
+		if variable.Type.IsBaseTypeLanguage() {
+			return fmt.Sprintf("%d", getLanguageTypeSize(variable.Type.GetName()))
+		}
+	}
+
+	member, isMember := symbol.(*symbols.StructMember)
+	if isMember {
+		if member.GetType().IsPointer() {
+			return fmt.Sprintf("%d", utils.PointerSize())
+		}
+
+		if member.GetType().IsBaseTypeLanguage() {
+			return fmt.Sprintf("%d", getLanguageTypeSize(member.GetType().GetName()))
+		}
+	}
+
+	return "?"
+}
+
+func calculateAlignment(symbol symbols.Indexable) string {
+	return ""
+}
+
+func getLanguageTypeSize(typeName string) uint {
+	size := uint(0)
+	switch typeName {
+	case "bool":
+		size = 1
+	case "ichar", "char":
+		size = 8
+	case "short", "ushort":
+		size = 16
+	case "int", "uint":
+		size = 32
+	case "long", "ulong":
+		size = 64
+	case "int128", "uint128":
+		size = 128
+	case "iptr", "uptr", "isz", "usz":
+		size = 0
+	}
+
+	return size
+}
diff --git a/server/pkg/symbols/type.go b/server/pkg/symbols/type.go
index 628dd24..92c0509 100644
--- a/server/pkg/symbols/type.go
+++ b/server/pkg/symbols/type.go
@@ -52,6 +52,10 @@ func (t *Type) SetModule(module string) {
 	t.module = module
 }
 
+func (t *Type) IsPointer() bool {
+	return t.pointer > 0
+}
+
 func (t Type) String() string {
 	pointerStr := strings.Repeat("*", t.pointer)
 	optionalStr := ""
diff --git a/server/pkg/utils/arch.go b/server/pkg/utils/arch.go
new file mode 100644
index 0000000..335747f
--- /dev/null
+++ b/server/pkg/utils/arch.go
@@ -0,0 +1,31 @@
+package utils
+
+import (
+	"runtime"
+)
+
+const (
+	CPU_UNKNOWN = iota
+	CPU_64      = 64
+	CPU_32      = 32
+)
+
+func CpuArchitecture() uint {
+	if runtime.GOARCH == "amd64" || runtime.GOARCH == "arm64" {
+		return CPU_64
+	} else if runtime.GOARCH == "386" || runtime.GOARCH == "arm" {
+		return CPU_32
+	}
+
+	return CPU_UNKNOWN
+}
+
+func PointerSize() uint {
+	arch := CpuArchitecture()
+
+	if arch != CPU_UNKNOWN {
+		return arch / 8
+	}
+
+	return 0
+}
diff --git a/server/pkg/utils/features.go b/server/pkg/utils/features.go
new file mode 100644
index 0000000..6ddf3b2
--- /dev/null
+++ b/server/pkg/utils/features.go
@@ -0,0 +1,17 @@
+package utils
+
+func getFeatureFlags() map[string]bool {
+	return map[string]bool{
+		"SIZE_ON_HOVER": false,
+	}
+}
+
+// Function to check if a specific feature is enabled
+func IsFeatureEnabled(feature string) bool {
+	flags := getFeatureFlags()
+	if enabled, exists := flags[feature]; exists {
+		return enabled
+	}
+	// Default behavior if feature flag is not found
+	return false
+}