{ config, lib, pkgs, ... }:

with lib;

let
  gitpkgs = import /nixpkgs {};
  fn = import (toString ../fn.nix) { inherit lib; };
  modefiles = fn.lst { p = (toString ./emacs); b = true; };
in rec {
#  nixpkgs.overlays = [
#    (import (builtins.fetchTarball {
#      url = https://github.com/nix-community/emacs-overlay/archive/master.tar.gz;
#    }))
#  ];
  imports = [
    ../options/emacs-init.nix
  ] ++ modefiles;

  programs.emacs.init = {
    enable = (elem "emacs" config.machine.pkgs);
    recommendedGcSettings = true;

    prelude = ''
      ;; Disable UI Clutter
      (menu-bar-mode -1)
      (tool-bar-mode -1)
      (scroll-bar-mode -1)
      (tooltip-mode -1)
      (blink-cursor-mode -1)
      (setq ring-bell-function 'ignore)
      (setq inhibit-startup-buffer-menu t)
      (setq use-dialog-box nil)
      (setq inhibit-startup-message t)
      (setq inhibit-splash-screen t)
      (setq initial-scratch-message nil)
      (fset 'yes-or-no-p 'y-or-n-p)
      (setq-default show-trailing-whitespace t)



      ;; Save and Backup behaviour
      (add-hook 'before-save-hook 'delete-trailing-whitespace)
      (setq create-lockfiles nil)
      (setq backup-directory-alist `(("." . "~/.emacs_saves")))
      (setq backup-by-copying t)
      (setq delete-old-versions t
            kept-new-versions 6
            kept-old-versions 2
            version-control t)



      ;; Tabs vs Spaces... I like Spaces
      (setq-default indent-tabs-mode nil
            tab-width 4
            c-basic-offset 4)



      ;; General Functions I want
      (put 'narrow-to-region 'disabled nil)
      (put 'upcase-region 'disabled nil)
      (put 'downcase-region 'disabled nil)



      ;; Global UI related Modes
      (global-display-line-numbers-mode)
      (setq display-line-numbers-width-start t)
      (setq display-line-numbers-grow-only t)
      (column-number-mode t)
      (global-hl-line-mode t)
      (size-indication-mode t)
      (show-paren-mode t)
      (setq split-height-threshold 200)
      (setq split-width-threshold nil)



      ;; Text Scaling
      (global-set-key (kbd "C-+") 'text-scale-increase)
      (global-set-key (kbd "C--") 'text-scale-decrease)



      ;; Font Config
      (defun set-fonts (frame)
        (interactive)
        "Adjust the font settings of FRAME so Emacs can display emoji and chinese properly."
        (set-fontset-font t 'ascii (font-spec :family "DejaVu Sans Mono") frame 'preprend)
        (set-fontset-font t 'big5 (font-spec :family "AR PL UMing TW") frame)
        (set-fontset-font t 'chinese-gbk (font-spec :family "AR PL UMing CN") frame)
        (set-fontset-font t 'symbol (font-spec :family "Symbola") frame 'prepend))

      ;; For when Emacs is started in GUI mode:
      (set-fonts nil)
      ;; Hook for when a frame is created with emacsclient
      ;; see https://www.gnu.org/software/emacs/manual/html_node/elisp/Creating-Frames.html
      (add-hook 'after-make-frame-functions 'set-fonts)

      ;; Fix keyboard input of 'dead-keys'
      (require 'iso-transl)
    '';
  };













### OLD STUFF
#  machine.pkgsets.emacs.pkgwrap =  [(gitpkgs.pkgs.emacsWithPackages (ps: with ps; config.machine.pkgsets.emacs.pkgs))];
#[
#    (pkgs.emacsWithPackagesFromUsePackage {
#      # config = (concatStringsSep "\n" machine.pkgsets.emacs.config);
#      config = ''
#        # (package-initialize)
#        # (org-babel-load-file "~/.emacs.d/configuration.org")
#      '';
#      package = pkgs.emacsGit;
#      extraEmacsPackages = (ep: with ep; config.machine.pkgsets.emacs.pkgs);
#    })
#  ];
#   machine.pkgsets.emacs.pkgs = with pkgs; with pkgs.emacsPackages; [
#     /* Theming */
#     solarized-theme color-theme-sanityinc-tomorrow moe-theme powerline moody minions
#     /*General Stuff */
#     rainbow-delimiters # color parenthesis by indentation
#     color-identifiers-mode
#     /* Python */
#     company-jedi pylint elpy flycheck-mypy
#     /* Git support */
#     magit
#     emms # multimedia support
#     wsd-mode
#     plantuml-mode
#     /* Other Stuff, not yet sorted */
#     mu4e-alert
#     google-translate
#     tramp
#     transmission
#     org-plus-contrib orgit ox-gfm ox-rst
#     easy-jekyll markdown-mode impatient-mode simple-httpd htmlize
#     eclim
#     auto-complete
#     pkgs.aspell pkgs.aspellDicts.en pkgs.aspellDicts.de
#     use-package diminish bind-key
#     smartparens
#     evil-surround evil-indent-textobject evil-cleverparens avy undo-tree
#     cdlatex #  for math expressions
#     helm
#     /* LaTeX */ auctex helm-bibtex cdlatex
#     markdown-mode
#     flycheck
#     pkgs.ledger
#     yaml-mode
#     company
#     # Irony is currently broken.
#     /* C/C++ */ irony company-irony  company-irony-c-headers flycheck-irony clang-format pkgs.clang-tools
#     /* Haskell */ haskell-mode flycheck-haskell
#     /* Org */ org org-ref pdf-tools org-bullets org-caldav
#     /* Rust */ rust-mode flycheck-rust racer
#     /* mail */ messages-are-flowing
#     /* Nix */ nix-buffer nix-mode nixos-options company-nixos-options nix-sandbox
#     paganini-theme
#     json-navigator
#     spaceline # modeline beautification
#     winum eyebrowse # window management
#     auto-compile
#     /* Maxima */ pkgs.maxima
#     visual-fill-column
#     web-mode
#     melpaStablePackages.idris-mode helm-idris
#     /* Java */
# #    projectile yasnippet lsp-mode hydra company-lsp lsp-ui lsp-java dap-mode
#     cl-lib meghanada autodisass-java-bytecode google-c-style realgud
#     weechat
#   ];
}