feat: better user cursor highlights

lua/codemp/utils.lua

@@ -165,26 +165,6 @@ local function buffer_set_content(buf, content, first, last)
 	end
 end
 
----@param buf integer buffer to highlight onto
----@param ns integer namespace for highlight
----@param group string highlight group
----@param start [integer, integer]
----@param fini [integer, integer]
-local function multiline_highlight(buf, ns, group, start, fini)
-	for i=start[1],fini[1] do
-		if i == start[1] and i == fini[1] then
-			local fini_col = fini[2]
-			if start[2] == fini[2] then fini_col = fini_col + 1 end
-			vim.api.nvim_buf_add_highlight(buf, ns, group, i, start[2], fini_col)
-		elseif i == start[1] then
-			vim.api.nvim_buf_add_highlight(buf, ns, group, i, start[2], -1)
-		elseif i == fini[1] then
-			vim.api.nvim_buf_add_highlight(buf, ns, group, i, 0, fini[2])
-		else
-			vim.api.nvim_buf_add_highlight(buf, ns, group, i, 0, -1)
-		end
-	end
-end
 
 local function buffer_len(buf)
 	local count = 0
@@ -203,8 +183,10 @@ local function separator()
 	end
 end
 
+local hash_fn = nil
+if native ~= nil then hash_fn = native.hash end
+
 return {
-	multiline_highlight = multiline_highlight,
 	cursor = {
 		position = cursor_position,
 	},
@@ -213,7 +195,7 @@ return {
 		get_content = buffer_get_content,
 		set_content = buffer_set_content,
 	},
-	hash = native.hash,
+	hash = hash_fn,
 	available_colors = available_colors,
 	color = color,
 	poller = async_poller,

lua/codemp/workspace.lua

@@ -88,6 +88,22 @@ local function register_cursor_handler(ws)
 				buffers.users[event.user] = event.buffer
 				local buffer_id = buffers.map_rev[event.buffer]
 				if buffer_id ~= nil then
+					vim.api.nvim_buf_set_extmark(
+						buffer_id,
+						user_hl[event.user].ns,
+						event.start[1],
+						event.start[2],
+						{
+							end_col = event.finish[1],
+							end_row = event.finish[2],
+							hl_group = user_hl[event.user].hi,
+							hl_eol = true,
+							virt_text_pos = "overlay",
+							virt_text = {
+								{ event.user, "InlayHint" }
+							},
+						}
+					)
 					utils.multiline_highlight(
 						buffer_id,
 						user_hl[event.user].ns,