{ config, lib, pkgs, ... }:
let
  strPalette = with pkgs.rice;
    palette.toRgbShortHex colorPalette;
  packages = with pkgs;
    [
      (pkgs.makeDesktopItem
        {
          name = "kakoune";
          exec = "kak %U";
          icon = "kakoune";
          desktopName = "Kakoune";
          comment = "Kakoune text editor";
          terminal = true;
          categories = [ "Development" ];
        })
    ] ++ [
      # editorconfig-core-c
      python3.pkgs.editorconfig
    ] ++ (
      lib.optionals (pkgs.devEnvironment.enableCpp) [
        clang-tools
      ]
    ) ++ (
      lib.optionals (pkgs.devEnvironment.enableData) [
        yaml-language-server
        nodePackages.vscode-langservers-extracted
      ]
    ) ++ (
      lib.optionals (pkgs.devEnvironment.enableHtml) [
        nodePackages.vscode-langservers-extracted
      ]
    ) ++ (
      lib.optionals (pkgs.devEnvironment.enableJavascript) [
        flow
      ]
    ) ++ (
      lib.optionals (pkgs.devEnvironment.enableLatex) [
        texlab
      ]
    ) ++ (
      lib.optionals (pkgs.devEnvironment.enableNix) [
        rnix-lsp
      ]
    ) ++ (
      with python3.pkgs;
      lib.optionals (pkgs.devEnvironment.enablePython) [
        black
        # pyls-black
        pyls-flake8
        pyls-isort
        # pyls-mypy
        python-lsp-server
      ]
    ) ++ (
      lib.optionals (pkgs.devEnvironment.enableRust) [
        cargo
        cargo-watch
        clippy
        rust-analyzer
        rustc
        rustfmt
      ]
    ) ++ (
      lib.optionals (pkgs.devEnvironment.enableShell) [
        nodePackages.bash-language-server
      ]
    ) ++ (
      lib.optionals (pkgs.devEnvironment.enableSpelling) [
        aspell
        aspellDicts.en
        aspellDicts.en-computers
        aspellDicts.en-science
        aspellDicts.it
      ]
    );
  plugins = with pkgs;
    [
      kakounePlugins.prelude-kak
      kakounePlugins.kak-lsp
      kakounePlugins.auto-pairs-kak
      kakounePlugins.powerline-kak
      kakounePlugins.connect-kak
    ];
in
{
  home.sessionVariables = {
    EDITOR = "kak";
    VISUAL = "kak";
  };
  programs.bash.shellAliases = {
    k = "kak";
  };
  programs.zsh.shellAliases = {
    k = "kak";
  };
  home.packages = packages;
  programs.kakoune = {
    enable = true;
    config = {
      colorScheme = "nord";
      tabStop = 2;
      indentWidth = 2;
      alignWithTabs = true;
      scrollOff = {
        lines = 5;
        columns = 3;
      };
      ui = {
        setTitle = true;
        changeColors = true;
        enableMouse = true;
      };
      wrapLines = {
        enable = true;
        word = true;
      };
      numberLines = {
        enable = true;
        highlightCursor = true;
      };
      keyMappings = with pkgs;
        [
          {
            mode = "normal";
            docstring = "Edit file";
            key = "<c-e>";
            effect = ":edit<space>";
          }
          {
            mode = "user";
            docstring = "Code actions";
            key = "a";
            effect = ":lsp-code-actions<ret>";
          }
          {
            mode = "user";
            docstring = "Comment block";
            key = "b";
            effect = ":comment-block<ret>";
          }
          {
            mode = "user";
            docstring = "Comment line";
            key = "l";
            effect = ":comment-line<ret>";
          }
          {
            mode = "user";
            docstring = "Copy to clipboard";
            key = "y";
            effect = "<a-|>${xclip}/bin/xclip -i -selection clipboard<ret>";
          }
          {
            mode = "user";
            docstring = "Format code with formatter";
            key = "f";
            effect = ":format<ret>";
          }
          {
            mode = "user";
            docstring = "Format code with LSP";
            key = "F";
            effect = ":lsp-formatting-sync<ret>";
          }
          {
            mode = "user";
            docstring = "Jump to definition";
            key = "d";
            effect = ":lsp-definition<ret>";
          }
          {
            mode = "user";
            docstring = "Rename object";
            key = "r";
            effect = ":lsp-rename-prompt<ret>";
          }
          {
            mode = "user";
            docstring = "Jump to type definition";
            key = "t";
            effect = ":lsp-type-definition<ret>";
          }
          {
            mode = "user";
            docstring = "List project diagnostics";
            key = "i";
            effect = ":lsp-diagnostics<ret>";
          }
          {
            mode = "user";
            docstring = "Paste from clipboard (after)";
            key = "P";
            effect = "<a-!>${xclip}/bin/xclip -selection clipboard -o<ret>";
          }
          {
            mode = "user";
            docstring = "Paste from clipboard (before)";
            key = "p";
            effect = "!${xclip}/bin/xclip -selection clipboard -o<ret>";
          }
          {
            mode = "user";
            docstring = "Show hover info";
            key = "q";
            effect = ":lsp-hover<ret>";
          }
          {
            mode = "user";
            docstring = "Spellcheck English";
            key = "S";
            effect = ":spell en<ret>";
          }
          {
            mode = "user";
            docstring = "Spellcheck";
            key = "s";
            effect = ":spell ";
          }
          {
            mode = "normal";
            docstring = "Try next snippet placeholder";
            key = "<c-n>";
            effect = "<a-;>: insert-c-n<ret>";
          }
          # {
          #   mode = "normal";
          #   docstring = "Search";
          #   key = "/";
          #   effect = "/(?i)";
          # }
          # {
          #   mode = "normal";
          #   docstring = "Reverse search";
          #   key = "<a-/>";
          #   effect = "<a-/>(?i)";
          # }
        ];
      hooks = with pkgs;
        [
          {
            name = "BufCreate";
            option = ".*";
            commands = "editorconfig-load";
          }
          # {
          #   name = "ModuleLoaded";
          #   option = "auto-pairs";
          #   commands = "auto-pairs-enable";
          # }
          {
            name = "ModuleLoaded";
            option = "powerline";
            commands = builtins.concatStringsSep "\n" [ "powerline-enable" ];
          }
        ] ++ (
          lib.optionals (pkgs.devEnvironment.enableLatex) [
            {
              name = "BufSetOption";
              option = "filetype=latex";
              commands = "set-option buffer formatcmd ${texlive.bin.latexindent}/bin/latexindent";
            }
          ]
        ) ++ (
          lib.optionals (pkgs.devEnvironment.enablePython) [
            {
              name = "BufSetOption";
              option = "filetype=python";
              commands = "set-option buffer formatcmd '${python3.pkgs.black}/bin/black -'";
            }
          ]
        ) ++ (
          lib.optionals (pkgs.devEnvironment.enableData) [
            {
              name = "BufSetOption";
              option = "filetype=(markdown|html|json|yaml|css|scss|less)";
              commands = "set-option buffer formatcmd ${nodePackages.prettier}/bin/prettier";
            }
          ]
        );
      # TODO add more formatters from https://github.com/mawww/kakoune/wiki/Format
    };
    extraConfig = builtins.concatStringsSep "\n" [
      "# Custom commands"
      "add-highlighter global/ regex \\h+$ 0:Error                   # Highlight trailing spaces"
      "eval %sh{kak-lsp --kakoune -s $kak_session}"
      "lsp-enable"
      ''
        def -hidden insert-c-n %{
         try %{
           lsp-snippets-select-next-placeholders
           exec '<a-;>d'
         } catch %{
           exec -with-hooks '<c-n>'
         }
        }
      ''
      "require-module powerline"
      "powerline-start"
      "require-module connect-broot"
      "require-module connect-lf"
      "require-module connect-rofi"
    ];
    plugins = plugins;
  };
  xdg.configFile."kak/colors/nord.kak".text = with strPalette;
    ''
      set-face global value rgb:${normal.magenta},default
      set-face global type rgb:${bright.white},default
      set-face global identifier rgb:${normal.cyan},default
      set-face global string rgb:${normal.green},default
      set-face global error rgb:${normal.red},default
      set-face global keyword rgb:${normal.blue},default
      set-face global operator rgb:${normal.blue},default
      set-face global attribute rgb:${bright.blue},default
      set-face global comment rgb:${bright.blue},default
      set-face global meta rgb:${normal.yellow},default
      set-face global Default rgb:${normal.white},default
      set-face global PrimarySelection rgb:${normal.black},rgb:${dark.yellow}
      set-face global SecondarySelection rgb:${normal.black},rgb:${dark.white}
      set-face global PrimaryCursor rgb:${normal.black},rgb:${normal.yellow}
      set-face global SecondaryCursor rgb:${normal.black},rgb:${normal.white}
      set-face global MenuForeground rgb:${normal.white},rgb:${bright.black}
      set-face global MenuBackground default,rgb:${normal.black}
      set-face global MenuInfo default,rgb:${normal.black}
      set-face global Information rgb:${dark.black},rgb:${normal.cyan}
      set-face global StatusLine rgb:${normal.white},rgb:${normal.black}
      set-face global StatusLineMode rgb:${normal.blue},rgb:${normal.black}
      set-face global StatusLineInfo rgb:${normal.blue},rgb:${normal.black}
      set-face global StatusLineValue rgb:${normal.blue},rgb:${normal.black}
      set-face global StatusCursor rgb:${dark.black},rgb:${normal.yellow}
      set-face global Prompt rgb:${normal.cyan},rgb:${normal.black}
      set-face global BufferPadding default,default
    '';
  xdg.configFile."kak-lsp/kak-lsp.toml".text = with pkgs;
    builtins.concatStringsSep "\n" (
      [
        ''
          snippet_support = false
          verbosity = 2
          [server]
          timeout = 1800 # seconds = 30 minutes
        ''
      ]
      ++ (
        lib.optional (pkgs.devEnvironment.enableCpp) ''
          [language.c_cpp]
          filetypes = ["c", "cpp"]
          roots = ["compile_commands.json", ".clangd"]
          command = "${clang-tools}/bin/clangd"
          offset_encoding = "utf-8"
        ''
      ) ++ (
        lib.optional (pkgs.devEnvironment.enableData) ''
          [language.json]
          filetypes = ["json"]
          roots = ["package.json"]
          command = "${nodePackages.vscode-langservers-extracted}/bin/vscode-json-language-server"
          args = ["--stdio"]
          [language.yaml]
          filetypes = ["yaml"]
          roots = [".git"]
          command = "${yaml-language-server}/bin/yaml-language-server"
          args = ["--stdio"]
          [language.yaml.settings]
          # See https://github.com/redhat-developer/yaml-language-server#language-server-settings
          # Defaults are at https://github.com/redhat-developer/yaml-language-server/blob/master/src/yamlSettings.ts
          yaml.format.enable = true
        ''
      ) ++ (
        lib.optional (pkgs.devEnvironment.enableGo) ''
          [language.go]
          filetypes = ["go"]
          roots = ["Gopkg.toml", "go.mod", ".git", ".hg"]
          command = "gopls"
          offset_encoding = "utf-8"
          settings_section = "gopls"
          [language.go.settings.gopls]
          # See https://github.com/golang/tools/blob/master/gopls/doc/settings.md
          # "build.buildFlags" = []
        ''
      )
      ++ (
        lib.optional (pkgs.devEnvironment.enableHtml) ''
          [language.html]
          filetypes = ["html"]
          roots = ["package.json"]
          command = "${nodePackages.vscode-langservers-extracted}/bin/vscode-html-language-server"
          args = ["--stdio"]
          [language.css]
          filetypes = ["css"]
          roots = ["package.json", ".git"]
          command = "${nodePackages.vscode-langservers-extracted}/bin/vscode-css-language-server"
          args = ["--stdio"]
          [language.less]
          filetypes = ["less"]
          roots = ["package.json", ".git"]
          command = "${nodePackages.vscode-langservers-extracted}/bin/vscode-css-language-server"
          args = ["--stdio"]
          [language.scss]
          filetypes = ["scss"]
          roots = ["package.json", ".git"]
          command = "${nodePackages.vscode-langservers-extracted}/bin/vscode-css-language-server"
          args = ["--stdio"]
        ''
      ) ++ (
        lib.optional (pkgs.devEnvironment.enableJavascript) ''
          [language.javascript]
          filetypes = ["javascript"]
          roots = [".flowconfig"]
          command = "${flow}/bin/flow"
          args = ["lsp"]
        ''
      ) ++ (
        lib.optional (pkgs.devEnvironment.enableLatex) ''
          [language.latex]
          filetypes = ["latex"]
          roots = [".git"]
          command = "${texlab}/bin/texlab"
          settings_section = "texlab"
          [language.latex.settings.texlab]
          # See https://github.com/latex-lsp/texlab/blob/master/src/options.rs
          # bibtexFormatter = "${texlab}/bin/texlab"
        ''
      ) ++ (
        lib.optional (pkgs.devEnvironment.enableNix) ''
          [language.nix]
          filetypes = ["nix"]
          roots = ["flake.nix", "shell.nix", ".git"]
          command = "${rnix-lsp}/bin/rnix-lsp"
        ''
      ) ++ (
        lib.optional (pkgs.devEnvironment.enablePython) ''
          [language.python]
          filetypes = ["python"]
          roots = ["requirements.txt", "setup.py", ".git", ".hg"]
          command = "${python3.pkgs.python-lsp-server}/bin/pylsp"
          offset_encoding = "utf-8"
          [language.python.settings]
          # See https://github.com/palantir/python-language-server#configuration
          # and https://github.com/palantir/python-language-server/blob/develop/vscode-client/package.json
          # "pyls.configurationSources" = ["flake8"]
        ''
      ) ++ (
        lib.optional (pkgs.devEnvironment.enableRust) ''
          [language.rust]
          filetypes = ["rust"]
          roots = ["Cargo.toml"]
          command = "${rust-analyzer}/bin/rust-analyzer"
          settings_section = "rust-analyzer"
          [language.rust.settings.rust-analyzer]
          hoverActions.enable = false # kak-lsp doesn't support this at the moment
          # cargo.features = []
          # See https://rust-analyzer.github.io/manual.html#configuration
          # If you get 'unresolved proc macro' warnings, you have two options
          # 1. The safe choice is two disable the warning:
          diagnostics.disabled = ["unresolved-proc-macro"]
          # 2. Or you can opt-in for proc macro support
          procMacro.enable = true
          cargo.loadOutDirsFromCheck = true
          # See https://github.com/rust-analyzer/rust-analyzer/issues/6448
        ''
      ) ++ (
        lib.optional (pkgs.devEnvironment.enableShell) ''
          [language.bash]
          filetypes = ["sh"]
          roots = [".git", ".hg"]
          command = "${nodePackages.bash-language-server}/bin/bash-language-server"
          args = ["start"]
        ''
      )
    );
}