chore(config): refactored config module

The config module has been rewritten and a new library called `collect`
has been added. This library provides utilities for setting options and
overriding options in the config module.

This also addresses #238 if it's caused by the one-level override of
user config.

lua/github-theme/config.lua

@@ -1,24 +1,37 @@
-local M = {}
-local types = require('github-theme.types')
+local collect = require('github-theme.lib.collect')
 
-M.default = {
-  colors = {},
-  comment_style = types.gt.HighlightStyle.Italic,
-  dark_float = false,
-  dark_sidebar = true,
-  dev = false,
-  function_style = types.gt.HighlightStyle.None,
+local M = { has_options = true }
+
+local defaults = {
+  theme_style = 'dark',
   hide_end_of_buffer = true,
   hide_inactive_statusline = true,
-  keyword_style = types.gt.HighlightStyle.Italic,
-  msg_area_style = types.gt.HighlightStyle.None,
+  comment_style = 'italic',
+  function_style = 'NONE',
+  keyword_style = 'Italic',
+  msg_area_style = 'NONE',
+  variable_style = 'NONE',
+  transparent = false,
+  dark_float = false,
+  dark_sidebar = true,
+  sidebars = {},
+  colors = {},
   overrides = function()
     return {}
   end,
-  sidebars = {},
-  theme_style = types.gt.ThemeStyle.Dark,
-  transparent = false,
-  variable_style = types.gt.HighlightStyle.None,
+  dev = false,
 }
 
+M.options = collect.deep_copy(defaults)
+
+function M.set_options(opts)
+  opts = opts or {}
+  M.options = collect.deep_extend(M.options, opts)
+  M.has_options = true
+end
+
+function M.reset()
+  M.options = collect.deep_copy(defaults)
+end
+
 return M

lua/github-theme/init.lua

@@ -5,16 +5,19 @@ local theme = require('github-theme.theme')
 local util = require('github-theme.util')
 local dep = require('github-theme.util.deprecation')
 
-M.setup = function(user_config)
-  local c = config.default
-  if user_config then
-    c = vim.tbl_deep_extend('force', config.default, user_config or {})
+local did_setup = false
+
+M.setup = function(opts)
+  did_setup = true
+
+  if opts then
+    config.set_options(opts)
   end
 
-  dep.check_deprecation(c)
+  dep.check_deprecation(config.options)
 
   -- Load colorscheme
-  util.load(theme.setup(c))
+  util.load(theme.setup(config.options))
 end
 
 return M

lua/github-theme/lib/collect.lua

@@ -0,0 +1,85 @@
+local M = {}
+
+--- Checks if a list-like (vector) table contains `value`.
+---@param t table Table to check
+---@param value any Value to compare
+---@returns true if `t` contains `value`
+function M.contains(t, value)
+  for _, v in ipairs(t) do
+    if v == value then
+      return true
+    end
+  end
+  return false
+end
+
+--- Merges recursively two or more map-like tables.
+---@param ... any Two or more map-like tables.
+---@return table Merged table
+function M.deep_extend(...)
+  local lhs = {}
+  for _, rhs in ipairs({ ... }) do
+    for k, v in pairs(rhs) do
+      if type(lhs[k]) == 'table' and type(v) == 'table' then
+        lhs[k] = M.deep_extend(lhs[k], v)
+      else
+        lhs[k] = v
+      end
+    end
+  end
+
+  return lhs
+end
+
+---Apply a function to each value in a table.
+---@param tbl table
+---@param f function (value)
+function M.map(tbl, f)
+  local t = {}
+  for k, v in pairs(tbl) do
+    t[k] = f(v)
+  end
+  return t
+end
+
+---Filter table based on function
+---@param tbl table Table to be filtered
+---@param func function Function to apply filter
+---@return table
+function M.filter(tbl, func)
+  local result = {}
+  for _, item in ipairs(tbl) do
+    if func(item) then
+      table.insert(result, item)
+    end
+  end
+  return M(result)
+end
+
+---Apply function to each element of table
+---@param tbl Table A list of elements
+---@param func function to be applied
+function M.each(tbl, func)
+  for _, item in ipairs(tbl) do
+    func(item)
+  end
+end
+
+function M.deep_copy(obj, seen)
+  if type(obj) ~= 'table' then
+    return obj
+  end
+  if seen and seen[obj] then
+    return seen[obj]
+  end
+
+  local s = seen or {}
+  local res = {}
+  s[obj] = res
+  for k, v in pairs(obj) do
+    res[M.deep_copy(k, s)] = M.deep_copy(v, s)
+  end
+  return setmetatable(res, getmetatable(obj))
+end
+
+return M