1 files changed, 60 insertions, 0 deletions
diff --git a/.config/nvim/lua/leaf/fold.lua b/.config/nvim/lua/leaf/fold.lua
new file mode 100644
index 0000000..6f8a0b5
--- /dev/null
+++ b/.config/nvim/lua/leaf/fold.lua
@@ -0,0 +1,60 @@
+local M = {}
+
+
+local F = vim.fn
+local V = vim.v
+
+
+local function find_plain_string(haystack, needle, start)
+   return haystack:find(needle, start or 1, true)
+end
+
+
+function M.foldexpr()
+   local current_line_indent = F.indent(V.lnum)
+   local task_level = math.floor(current_line_indent / F.shiftwidth())
+   if V.lnum == F.line('$') then
+      return task_level
+   end
+   local next_line_indent = F.indent(V.lnum + 1)
+   if current_line_indent < next_line_indent then
+      return ('>%d'):format(task_level + 1)
+   else
+      return task_level
+   end
+end
+
+
+function M.foldtext()
+   local foldstart = V.foldstart
+   local foldend = V.foldend
+   local shiftwidth = F.shiftwidth()
+   local current_line_indent = F.indent(foldstart)
+
+   local todo = 0
+   local done = 0
+   for i = foldstart + 1, foldend do
+      local line = F.getline(i)
+      local line_indent = F.indent(i)
+      if line_indent == current_line_indent + shiftwidth then
+         if find_plain_string(line, '[x] ') then
+            done = done + 1
+         elseif find_plain_string(line, '[ ] ') then
+            todo = todo + 1
+         elseif find_plain_string(line, '[-] ') then
+            done = done + 1
+         end
+      end
+   end
+
+   local progress
+   if done + todo == 0 then
+      progress = '...'
+   else
+      progress = ('  [%d/%d]'):format(done, done + todo)
+   end
+   return F.getline(foldstart) .. progress
+end
+
+
+return M