refactor: cleanup reminder and use stream for performance

module/reminder.lua

@@ -1,68 +1,51 @@
-local gtable = require("gears.table")
 local notifs = require("util.notifs")
 local path = require("util.path")
 local read_async = require("util.file.read_async")
 local spawn = require("util.spawn")
 local stream = require("stream")
 local strings = require("util.strings")
-local tables = require("util.tables")
 
----Return a table of permutations of extensions
----Note: this boils down to ("%s%s"):format. It does *no* path manipulation.
----@param filepath string|string[]
----@param exts string[]
----@param include_original boolean? Should `path` be included in the result? Default: true
----@return string[]
-local function add_suffix(filepath, exts, include_original)
-  include_original = include_original == nil and true or include_original -- default to true
-  if type(filepath) == "table" then
-    local ret = include_original and gtable.clone(filepath, false) or {}
-    return stream
-      .new(filepath)
-      :map(function(p) -- Don't include original to remove duplicates
-        return add_suffix(p, exts, false)
-      end)
-      :reduce(ret, gtable.merge)
-  end
-  return (
-    stream
-      .new(exts)
-      :map(function(ext) return ("%s%s"):format(filepath, ext) end)
-      :toarray(include_original and { filepath } or nil)
-  )
-end
---- Only all caps or all lower case is allowed
-local home_reminder_paths = tables.map_val({ "reminder", ".reminder", ".todo", "todo" }, string.lower)
-local extensions = { ".txt", ".md" }
---  These should be /todo, /reminder, ...
-local files_wo_extensions = add_suffix(path.sep, home_reminder_paths, false)
-local files_wo_extensions_allow_cap =
-  gtable.join(files_wo_extensions, tables.map_val(files_wo_extensions, string.upper))
---- These should be /todo, /todo.txt, /todo.md, ...
-local allowed_files = add_suffix(files_wo_extensions_allow_cap, extensions, true)
---- reminder/todo.txt, todo.txt, .reminder.md, ...
-local paths = add_suffix(tables.map_val(home_reminder_paths, path.get_home), gtable.join(extensions, allowed_files))
-local index = 1
+--- Note: the order of this matters, as the first one is the one that is used.
+--- PERF: I use todo more often than reminder, so I put it first, this saves ~30 iterations.
+local names = { "todo", "reminder" }
+local extensions = { ".md", ".txt" }
+
+local path_stream = stream
+  .new(names)
+  -- todo, .todo, .reminder, reminder
+  :flatmap(function(p) return { p, "." .. p } end)
+  -- todo, TODO, Todo, ...
+  :flatmap(function(p) return { p:lower(), p:gsub("^%l", string.upper), p:upper() } end)
+  -- todo, todo/index, ...
+  :flatmap(function(p) return { p, path.join(p, "index") } end)
+  --- todo, todo.txt, todo.md, todo/index.txt, todo/index.md, ...
+  :flatmap(function(p) ---@param p string
+    return stream.concat(stream.of(p), stream.new(extensions):map(function(e) return p .. e end))
+  end)
+  -- /home/user/todo, /home/user/todo/index, ...
+  :map(path.get_home)
 
 local function handler(content, _, fpath)
   if not content then -- Repeat until we find one.
-    index = index + 1 -- Try the next one.
-    if not paths[index] then return end
-    return read_async(paths[index], handler)
+    local next, done = path_stream:next() -- Try the next one.
+    if done then return end -- there are no more
+    return read_async(next, handler)
   end
   if #content == 0 or content:find("^%s*$") then return end -- just whitespace
 
   local msg = content:gsub("^\n*", ""):gsub("\n*$", ""):gsub("\n\n\n", "\n\n")
   return notifs.info(msg, { title = ("Reminder (%s)"):format(path.tildify(fpath)) })
 end
+read_async(path_stream:next(), handler)
 
+--- Spawn the `todo` command to get the todo list
 spawn.async_success({ "todo", "count" }, function(stdout_count)
-  if tonumber(stdout_count) == 0 then return end
-  spawn.async_success({ "todo", "list" }, function(stdout)
+  stdout_count = tonumber(stdout_count)
+  if not stdout_count or stdout_count == 0 then return end
+  return spawn.async_success({ "todo", "list" }, function(stdout)
     local out = strings.trim(stdout)
     if out == "" then return end
-    return notifs.info(out, { title = "Todo" })
+    local todo_s = strings.pluralize("todo", stdout_count)
+    return notifs.info(out, { title = ("You have %d %s"):format(stdout_count, todo_s) })
   end)
 end)
-
-return read_async(paths[index], handler)