From 5ef11419116578a6cbfb0a18674e590237ded080 Mon Sep 17 00:00:00 2001
From: Kristijan Husak <husakkristijan@gmail.com>
Date: Mon, 9 Oct 2023 17:03:05 +0200
Subject: [PATCH] refactor: Use promises for readfile

---
 lua/orgmode/colors/todo_highlighter.lua | 44 ++++++++++---------------
 lua/orgmode/parser/file.lua             | 12 ++-----
 lua/orgmode/utils/init.lua              | 40 ++++++++++------------
 3 files changed, 39 insertions(+), 57 deletions(-)

diff --git a/lua/orgmode/colors/todo_highlighter.lua b/lua/orgmode/colors/todo_highlighter.lua
index 3dadb4c8c..c5d5a912e 100644
--- a/lua/orgmode/colors/todo_highlighter.lua
+++ b/lua/orgmode/colors/todo_highlighter.lua
@@ -1,4 +1,4 @@
-local config = require('orgmode.config')
+local Promise = require('orgmode.utils.promise')
 local highlights = require('orgmode.colors.highlights')
 local tree_utils = require('orgmode.utils.treesitter')
 local utils = require('orgmode.utils')
@@ -13,44 +13,36 @@ local function add_todo_keyword_highlights()
     return
   end
 
-  local all_lines = {}
+  local actions = {}
   for i, _ in pairs(query_files) do
     if i ~= #query_files then
-      utils.readfile(
-        query_files[i],
-        vim.schedule_wrap(function(err, lines)
-          if err then
-            return
-          end
-          for _, v in ipairs(lines) do
-            table.insert(all_lines, v)
-          end
-        end)
-      )
+      table.insert(actions, utils.readfile(query_files[i]))
     else
-      utils.readfile(
-        query_files[i],
-        vim.schedule_wrap(function(err, lines)
-          if err then
-            return
-          end
+      table.insert(
+        actions,
+        utils.readfile(query_files[i]):next(function(lines)
           for face_name, face_hl in pairs(faces) do
             table.insert(
               lines,
               string.format([[(item . (expr) @%s @nospell (#eq? @%s %s))]], face_hl, face_hl, face_name)
             )
           end
-          for _, v in ipairs(lines) do
-            table.insert(all_lines, v)
-          end
-          vim.treesitter.query.set('org', 'highlights', table.concat(all_lines, '\n'))
-          if vim.bo.filetype == 'org' then
-            tree_utils.restart_highlights()
-          end
+          return lines
         end)
       )
     end
   end
+
+  return Promise.all(actions):next(function(line_parts)
+    local all_lines = {}
+    for _, line_part in ipairs(line_parts) do
+      utils.concat(all_lines, line_part)
+    end
+    vim.treesitter.query.set('org', 'highlights', table.concat(all_lines, '\n'))
+    if vim.bo.filetype == 'org' then
+      tree_utils.restart_highlights()
+    end
+  end)
 end
 
 return {
diff --git a/lua/orgmode/parser/file.lua b/lua/orgmode/parser/file.lua
index 0420ca247..58d91aef2 100644
--- a/lua/orgmode/parser/file.lua
+++ b/lua/orgmode/parser/file.lua
@@ -151,15 +151,9 @@ function File.load(path, callback)
     return callback(nil)
   end
   local category = vim.fn.fnamemodify(path, ':t:r')
-  utils.readfile(
-    path,
-    vim.schedule_wrap(function(err, content)
-      if err then
-        return callback(nil)
-      end
-      return callback(File.from_content(content, category, path, ext == 'org_archive'))
-    end)
-  )
+  utils.readfile(path):next(vim.schedule_wrap(function(content)
+    return callback(File.from_content(content, category, path, ext == 'org_archive'))
+  end))
 end
 
 ---@param content table
diff --git a/lua/orgmode/utils/init.lua b/lua/orgmode/utils/init.lua
index 7b5a720e7..767eee525 100644
--- a/lua/orgmode/utils/init.lua
+++ b/lua/orgmode/utils/init.lua
@@ -6,32 +6,28 @@ local debounce_timers = {}
 local query_cache = {}
 local tmp_window_augroup = vim.api.nvim_create_augroup('OrgTmpWindow', { clear = true })
 
----@param file string
----@param callback function
----@param as_string? boolean
-function utils.readfile(file, callback, as_string)
-  uv.fs_open(file, 'r', 438, function(err1, fd)
-    if err1 then
-      return callback(err1)
-    end
-    uv.fs_fstat(fd, function(err2, stat)
-      if err2 then
-        return callback(err2)
+function utils.readfile(file)
+  return Promise.new(function(resolve, reject)
+    uv.fs_open(file, 'r', 438, function(err1, fd)
+      if err1 then
+        return reject(err1)
       end
-      uv.fs_read(fd, stat.size, 0, function(err3, data)
-        if err3 then
-          return callback(err3)
+      uv.fs_fstat(fd, function(err2, stat)
+        if err2 then
+          return reject(err2)
         end
-        uv.fs_close(fd, function(err4)
-          if err4 then
-            return callback(err4)
+        uv.fs_read(fd, stat.size, 0, function(err3, data)
+          if err3 then
+            return reject(err3)
           end
-          local lines = data
-          if not as_string then
-            lines = vim.split(data, '\n')
+          uv.fs_close(fd, function(err4)
+            if err4 then
+              return reject(err4)
+            end
+            local lines = vim.split(data, '\n')
             table.remove(lines, #lines)
-          end
-          return callback(nil, lines)
+            return resolve(lines)
+          end)
         end)
       end)
     end)