Implement todo toggle.

README.md

@@ -29,6 +29,16 @@ vim.keymap.set("n", "mp", "<cmd>HeaderPromote<cr>", { desc = "Promote markdown h
 
 You can also just use something like lazy.nvim and load the plugin only on markdown and have this be set in config. But that will leave this binding on even in a non markdown file tho.
 
+### Toggle to do items
+
+Very simple function that toggles existing todo item's. It doesn't go out of it's way to create new todo item's or anythin like that, but just toggles existing toggle items. It also doesn't go out of it's way to toggle the paren't todo ( it's just a simple jump people ).
+
+> example mapping
+
+```lua
+vim.keymap.set("n", "mt", "<cmd>ToDoToggle<cr>", { desc = "Toggle Existing Todo Item" })
+```
+
 ## Small feature set
 
 I plan for this plugin to be very small and only have a small amount of feature's because there are already a lot of really good neovim plugins for writting markdown but some of them are really big and do a lot of stuff you might don't want them to do.

lua/md-tools/init.lua

@@ -1,5 +1,32 @@
-local M = {}
 local header_regex = "^(#+) (.+)"
+local todo_symbols = { " ", "-", "X", "D" }
+
+local table_lenght = function(T)
+	local count = 0
+	for _ in pairs(T) do
+		count = count + 1
+	end
+	return count
+end
+
+local get_todo = function(line)
+	local todo = nil
+	local index = nil
+	for n, v in ipairs(todo_symbols) do
+		if v == "-" then
+			v = "%-"
+		end
+		local ul = "^%s*[+*-]%s+%[" .. v .. "%]%s+"
+		local ol = "^%s*%d+%.%s+%[" .. v .. "%]%s+"
+		if line:match(ul, nil) or line:match(ol, nil) then
+			todo = v
+			index = n
+		end
+	end
+	return todo, index
+end
+
+local M = {}
 
 M.headerControl = function(action)
 	local current_line = vim.api.nvim_get_current_line()
@@ -22,4 +49,20 @@ M.headerControl = function(action)
 	end
 end
 
+M.toggleTodo = function()
+	local current_line = vim.api.nvim_get_current_line()
+	local row = vim.api.nvim_win_get_cursor(0)[1]
+
+	local todo, index = get_todo(current_line)
+	if todo then
+		local symbol = todo_symbols[index + 1]
+		-- make sure symbol is set to first character if index is too big
+		if index == table_lenght(todo_symbols) then
+			symbol = todo_symbols[1]
+		end
+		local first, last = current_line:find("%[" .. todo .. "%]")
+		vim.api.nvim_buf_set_text(0, row - 1, first, row - 1, last - 1, { symbol })
+	end
+end
+
 return M