4 files changed, 207 insertions, 0 deletions
diff --git a/.config/nvim/lua/leaf/calendar.lua b/.config/nvim/lua/leaf/calendar.lua
new file mode 100644
index 0000000..f998785
--- /dev/null
+++ b/.config/nvim/lua/leaf/calendar.lua
@@ -0,0 +1,43 @@
+local M = {}
+
+
+local floor = math.floor
+
+
+M.MON = 1
+M.TUE = 2
+M.WED = 3
+M.THU = 4
+M.FRI = 5
+M.SAT = 6
+M.SUN = 7
+
+
+function M.calc_week_of_day(y, m, d)
+   -- Zeller's congruence
+   if m == 1 or m == 2 then
+      m = m + 12
+      y = y - 1
+   end
+   local C = floor(y / 100)
+   local Y = y % 100
+   local G = 5*C + floor(C/4)
+   return 1 + (d + floor(26 * (m+1) / 10) + Y + floor(Y/4) + G + 5) % 7
+end
+
+
+function M.translate_week_of_day(w, locale)
+   -- assert(locale == 'ja_JP')
+   return ({
+      [M.MON] = '月',
+      [M.TUE] = '火',
+      [M.WED] = '水',
+      [M.THU] = '木',
+      [M.FRI] = '金',
+      [M.SAT] = '土',
+      [M.SUN] = '日',
+   })[w]
+end
+
+
+return M
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
diff --git a/.config/nvim/lua/leaf/indent.lua b/.config/nvim/lua/leaf/indent.lua
new file mode 100644
index 0000000..d1df34a
--- /dev/null
+++ b/.config/nvim/lua/leaf/indent.lua
@@ -0,0 +1,16 @@
+local M = {}
+
+local F = vim.fn
+local V = vim.v
+
+
+function M.indentexpr()
+   local lnum = V.lnum
+   if lnum == 0 then
+      return 0
+   end
+   return F.indent(lnum - 1)
+end
+
+
+return M
diff --git a/.config/nvim/lua/leaf/init.lua b/.config/nvim/lua/leaf/init.lua
new file mode 100644
index 0000000..c389ffd
--- /dev/null
+++ b/.config/nvim/lua/leaf/init.lua
@@ -0,0 +1,88 @@
+local M = {}
+
+
+local A = vim.api
+local F = vim.fn
+
+local TASK_STATUS_PATTERN = [=[\[[ x-]\] ]=]
+local TASK_STATUS_PATTERN_EXCEPT_DONE = [=[\[[ -]\] ]=]
+local TASK_STATUS_PATTERN_EXCEPT_CANCELED = [=[\[[ x]\] ]=]
+-- op = T
+--    T => T
+--    D => T
+--    C => T
+-- op = D
+--    T => D
+--    D => D
+--    C => C
+-- op = C
+--    T => C
+--    D => D
+--    C => C
+
+
+local function vim_match(s, pattern)
+   return vim.regex(pattern):match_str(s)
+end
+
+local function switch_task_status_internal(line_num, op, is_subtask)
+   local line = F.getline(line_num)
+   local pattern
+   if is_subtask then
+      if op == ' ' then
+         pattern = TASK_STATUS_PATTERN
+      elseif op == 'x' then
+         pattern = TASK_STATUS_PATTERN_EXCEPT_CANCELED
+      elseif op == '-' then
+         pattern = TASK_STATUS_PATTERN_EXCEPT_DONE
+      else
+         assert('unexpected op: ' .. tostring(op))
+      end
+   else
+      pattern = TASK_STATUS_PATTERN
+   end
+   if vim_match(line, pattern) then
+      local replacement = ('[%s] '):format(op)
+      F.setline(line_num, F.substitute(line, pattern, replacement, ''))
+      return true
+   else
+      return false
+   end
+end
+
+
+function M.checkbox(check, char)
+   local line = F.getline('.')
+   if vim_match(line, [[^\s*$]]) and #line % F.shiftwidth() == 0 then
+      return check and '[x] ' or '[ ] '
+   else
+      return char
+   end
+end
+
+function M.switch_task_status(op)
+   switch_task_status_internal(F.line('.'), op)
+end
+
+function M.switch_task_status_rec(op)
+   local current_line_num = F.line('.')
+   local replaced = switch_task_status_internal(current_line_num, op)
+   if not replaced then
+      return
+   end
+   local last_line_num = F.line('$')
+   if current_line_num == last_line_num then
+      return
+   end
+
+   local base_indent_level = F.indent('.')
+   for l = current_line_num + 1, last_line_num do
+      if F.indent(l) <= base_indent_level then
+         break
+      end
+      switch_task_status_internal(l, op, true)
+   end
+end
+
+
+return M