From ba909dbcea7940ba64f790355fb33838015541e8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Mickae=CC=88l=20Menu?= <mickael.menu@gmail.com>
Date: Sat, 3 Apr 2021 16:28:25 +0200
Subject: [PATCH] Add hover

---
 adapter/lsp/server.go | 42 +++++++++++++++++++++++++++++++++++++++++-
 go.sum                |  2 ++
 2 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/adapter/lsp/server.go b/adapter/lsp/server.go
index 245b4396..e25e6f6e 100644
--- a/adapter/lsp/server.go
+++ b/adapter/lsp/server.go
@@ -2,6 +2,7 @@ package lsp
 
 import (
 	"fmt"
+	"io/ioutil"
 	"net/url"
 	"path/filepath"
 	"strings"
@@ -186,7 +187,46 @@ func NewServer(opts ServerOpts) *Server {
 	}
 
 	handler.TextDocumentHover = func(context *glsp.Context, params *protocol.HoverParams) (*protocol.Hover, error) {
-		return nil, nil
+		doc, ok := server.documents[params.TextDocument.URI]
+		if !ok {
+			return nil, nil
+		}
+
+		zk, err := server.container.Zk()
+		if err != nil {
+			return nil, err
+		}
+
+		db, _, err := server.container.Database(false)
+		if err != nil {
+			return nil, err
+		}
+
+		var target string
+		err = db.WithTransaction(func(tx sqlite.Transaction) error {
+			finder := sqlite.NewNoteDAO(tx, server.container.Logger)
+			link, err := doc.DocumentLinkAt(params.Position)
+			if link == nil || err != nil {
+				return err
+			}
+			target, err = server.targetForHref(link.Href, zk.Path, finder)
+			return err
+		})
+		if err != nil || target == "" || strutil.IsURL(target) {
+			return nil, err
+		}
+		target = strings.TrimPrefix(target, "file://")
+		contents, err := ioutil.ReadFile(target)
+		if err != nil {
+			return nil, err
+		}
+
+		return &protocol.Hover{
+			Contents: protocol.MarkupContent{
+				Kind:  protocol.MarkupKindMarkdown,
+				Value: string(contents),
+			},
+		}, nil
 	}
 
 	handler.TextDocumentDocumentLink = func(context *glsp.Context, params *protocol.DocumentLinkParams) ([]protocol.DocumentLink, error) {
diff --git a/go.sum b/go.sum
index 3376ef03..63d55967 100644
--- a/go.sum
+++ b/go.sum
@@ -510,6 +510,8 @@ github.com/tj/assert v0.0.0-20190920132354-ee03d75cd160 h1:NSWpaDaurcAJY7PkL8Xt0
 github.com/tj/assert v0.0.0-20190920132354-ee03d75cd160/go.mod h1:mZ9/Rh9oLWpLLDRpvE+3b7gP/C2YyLFYxNmcLnPTMe0=
 github.com/tj/go-naturaldate v1.3.0 h1:OgJIPkR/Jk4bFMBLbxZ8w+QUxwjqSvzd9x+yXocY4RI=
 github.com/tj/go-naturaldate v1.3.0/go.mod h1:rpUbjivDKiS1BlfMGc2qUKNZ/yxgthOfmytQs8d8hKk=
+github.com/tliron/glsp v0.0.0-20210308190902-c7ec7df19257 h1:EIMeclnZjLgYIUs06pWOo+wIuOji9Q4Qz0MaU3va198=
+github.com/tliron/glsp v0.0.0-20210308190902-c7ec7df19257/go.mod h1:ouzTGvQteTU4hdsG+32vIx0if7E9CzMa64d7tYJJ91g=
 github.com/tliron/kutil v0.1.22 h1:VnwZ6YlTao2ISmm9wdv8CnVy5BjROBPpG65qIRc1LtE=
 github.com/tliron/kutil v0.1.22/go.mod h1:HkG4xQS2/BHI8EO9WfdOwnlUil7NhY/wmiV7U1uwEYw=
 github.com/tliron/yamlkeys v1.3.5/go.mod h1:8kJ1A/1s3p/I3MQUAbtv72dPEyQGoh0ZkQp0UAkABBo=