From 4e183d543c6c388b291fb409dcb913e2698c650f Mon Sep 17 00:00:00 2001
From: Myzel394 <50424412+Myzel394@users.noreply.github.com>
Date: Fri, 18 Oct 2024 19:10:24 +0200
Subject: [PATCH] feat(hosts): Add signature help; Improvements

---
 .../handlers/hosts/handlers/signature_help.go | 58 +++++++++++++++++++
 .../hosts/lsp/text-document-signature.go      | 31 ++++++++++
 .../ssh_config/handlers/signature_help.go     |  9 +--
 .../text-document-signature-help.go           |  3 +-
 4 files changed, 96 insertions(+), 5 deletions(-)
 create mode 100644 server/handlers/hosts/handlers/signature_help.go
 create mode 100644 server/handlers/hosts/lsp/text-document-signature.go

diff --git a/server/handlers/hosts/handlers/signature_help.go b/server/handlers/hosts/handlers/signature_help.go
new file mode 100644
index 0000000..1a77dec
--- /dev/null
+++ b/server/handlers/hosts/handlers/signature_help.go
@@ -0,0 +1,58 @@
+package handlers
+
+import (
+	"config-lsp/common"
+	"config-lsp/handlers/hosts/ast"
+
+	protocol "github.com/tliron/glsp/protocol_3_16"
+)
+
+func GetEntrySignatureHelp(
+	entry *ast.HostsEntry,
+	cursor common.CursorPosition,
+) *protocol.SignatureHelp {
+	var index uint32
+
+	if entry == nil || entry.IPAddress == nil || entry.IPAddress.Location.ContainsPosition(cursor) {
+		index = 0
+	} else if entry.Hostname == nil || entry.Hostname.Location.ContainsPosition(cursor) {
+		index = 1
+	} else {
+		index = 2
+	}
+
+	signature := uint32(0)
+
+	return &protocol.SignatureHelp{
+		ActiveSignature: &signature,
+		Signatures: []protocol.SignatureInformation{
+			{
+				Label:           "<ip address> <hostname> [<alias>...]",
+				ActiveParameter: &index,
+				Parameters: []protocol.ParameterInformation{
+					{
+						Label: []uint32{
+							0,
+							uint32(len("<ip address>")),
+						},
+						Documentation: "The ip address to forward to",
+					},
+					{
+						Label: []uint32{
+							uint32(len("<ip address>")),
+							uint32(len("<ip address> ") + len("<hostname>")),
+						},
+						Documentation: "The hostname to forward to",
+					},
+					{
+						Label: []uint32{
+							uint32(len("<ip address> ") + len("<hostname>")),
+							uint32(len("<ip address> ") + len("<hostname> ") + len("[<alias>...]")),
+						},
+						Documentation: "An optional list of aliases that can also forward",
+					},
+				},
+			},
+		},
+	}
+}
diff --git a/server/handlers/hosts/lsp/text-document-signature.go b/server/handlers/hosts/lsp/text-document-signature.go
new file mode 100644
index 0000000..e79efb3
--- /dev/null
+++ b/server/handlers/hosts/lsp/text-document-signature.go
@@ -0,0 +1,31 @@
+package lsp
+
+import (
+	"config-lsp/common"
+	"config-lsp/handlers/hosts"
+	"config-lsp/handlers/hosts/ast"
+	"config-lsp/handlers/hosts/handlers"
+
+	"github.com/tliron/glsp"
+	protocol "github.com/tliron/glsp/protocol_3_16"
+)
+
+func TextDocumentSignatureHelp(context *glsp.Context, params *protocol.SignatureHelpParams) (*protocol.SignatureHelp, error) {
+	document := hosts.DocumentParserMap[params.TextDocument.URI]
+
+	line := uint32(params.Position.Line)
+	cursor := common.LSPCharacterAsCursorPosition(params.Position.Character)
+
+	if _, found := document.Parser.CommentLines[line]; found {
+		// Comment
+		return nil, nil
+	}
+
+	entry, found := document.Parser.Tree.Entries.Get(line)
+
+	if !found {
+		return handlers.GetEntrySignatureHelp(nil, cursor), nil
+	} else {
+		return handlers.GetEntrySignatureHelp(entry.(*ast.HostsEntry), cursor), nil
+	}
+}
diff --git a/server/handlers/ssh_config/handlers/signature_help.go b/server/handlers/ssh_config/handlers/signature_help.go
index 5bdacbb..f93ca93 100644
--- a/server/handlers/ssh_config/handlers/signature_help.go
+++ b/server/handlers/ssh_config/handlers/signature_help.go
@@ -20,6 +20,7 @@ func GetOptionSignatureHelp(
 	}
 
 	signature := uint32(0)
+
 	return &protocol.SignatureHelp{
 		ActiveSignature: &signature,
 		Signatures: []protocol.SignatureInformation{
@@ -37,7 +38,7 @@ func GetOptionSignatureHelp(
 					{
 						Label: []uint32{
 							uint32(len("<option>")),
-							uint32(len("<option>") + len("<value>") + 1),
+							uint32(len("<option> ") + len("<value>")),
 						},
 						Documentation: "The value for the option",
 					},
@@ -90,7 +91,7 @@ func GetMatchSignatureHelp(
 					{
 						Label: []uint32{
 							uint32(len("Host <criteria> ")),
-							uint32(len("Host <criteria> ") + len("<values>") + 1),
+							uint32(len("Host <criteria> ") + len("<values>")),
 						},
 						Documentation: "Values for the criteria",
 					},
@@ -132,14 +133,14 @@ func GetHostSignatureHelp(
 					{
 						Label: []uint32{
 							uint32(len("Host ")),
-							uint32(len("Host ") + len("<host1>") + 1),
+							uint32(len("Host ") + len("<host1>")),
 						},
 						Documentation: "A host that should match",
 					},
 					{
 						Label: []uint32{
 							uint32(len("Host <host1> ")),
-							uint32(len("Host <host1> ") + len("[<host2> ...]") + 1),
+							uint32(len("Host <host1> ") + len("[<host2> ...]")),
 						},
 						Documentation: "Additional (optional) hosts that should match",
 					},
diff --git a/server/root-handler/text-document-signature-help.go b/server/root-handler/text-document-signature-help.go
index a144644..df0a382 100644
--- a/server/root-handler/text-document-signature-help.go
+++ b/server/root-handler/text-document-signature-help.go
@@ -2,6 +2,7 @@ package roothandler
 
 import (
 	aliases "config-lsp/handlers/aliases/lsp"
+	hosts "config-lsp/handlers/hosts/lsp"
 	sshconfig "config-lsp/handlers/ssh_config/lsp"
 	sshdconfig "config-lsp/handlers/sshd_config/lsp"
 
@@ -24,7 +25,7 @@ func TextDocumentSignatureHelp(context *glsp.Context, params *protocol.Signature
 
 	switch *language {
 	case LanguageHosts:
-		return nil, nil
+		return hosts.TextDocumentSignatureHelp(context, params)
 	case LanguageSSHDConfig:
 		return sshdconfig.TextDocumentSignatureHelp(context, params)
 	case LanguageSSHConfig: