args @ { config, pkgs, lib, ... }:
let
  utils = import ./utils.nix args;

  colorscheme = {
    plugin = utils.pluginGit
      "eb82712f86319272f4b7b9dbb4ec6df650e6987f"
      "EdenEast/nightfox.nvim";
    config = ''
      vim.cmd("colorscheme nordfox")
    '';
  };

  lualine = {
    plugin = pkgs.vimPlugins.lualine-nvim;
    config = ''
      require("lualine").setup {
        sections = {
          lualine_x = { "encoding", "filetype" },
          lualine_y = {
            require("utils.statusline").get_active_lsp,
            require("utils.statusline").get_dap_status,
            require("utils.statusline").get_autoexpand_status,
          },
          lualine_z = { "%c:%l:%%%p" },
        },
      }
    '';
  };

  nvim-cmp = {
    plugin = pkgs.vimPlugins.nvim-cmp;
    config = ''
      require("utils.cmp").setup()
    '';
  };

  nvim-dap = {
    plugin = utils.pluginGit
      "fc880e82059eb21c0fa896be60146e5f17680648"
      "mfussenegger/nvim-dap";
    config = ''
      require("dap").defaults.fallback.terminal_win_cmd = function()
        return vim.api.nvim_create_buf(
          true,  -- listed
          true   -- scratch
        )
      end
      ${config.programs.neovim.nvim-dap}
    '';
  };

  nvim-lspconfig = {
    plugin = pkgs.vimPlugins.nvim-lspconfig;
    config = config.programs.neovim.nvim-lspconfig;
  };

  nvim-telescope = {
    plugin = pkgs.vimPlugins.telescope-nvim;
    config = ''
      require("utils.telescope").setup()
    '';
  };

  nvim-treesitter = {
    plugin = (pkgs.vimPlugins.nvim-treesitter.withPlugins (
      ps: with ps; [
        bash
        c
        elixir
        heex
        html
        lua
        markdown
        nix
        python
        typescript
      ]
    ));
    config = ''
      require("utils.treesitter").setup()
    '';
  };
in
{
  options.programs.neovim = {
    nvim-dap = lib.mkOption {
      type = lib.types.lines;
      example = ''
        require("...").nvim_dap()
      '';
      description = lib.mdDoc ''
        Language-specific configurations for the `nvim-dap` plugin.
      '';
    };

    nvim-lspconfig = lib.mkOption {
      type = lib.types.lines;
      example = ''
        require("...").nvim_lspconfig()
      '';
      description = lib.mdDoc ''
        Language-specific configurations for the `nvim-lspconfig` plugin.
      '';
    };
  };

  config = {
    home.packages = with pkgs; [
      ripgrep
    ];

    programs.neovim = {
      defaultEditor = true;
      plugins = map (p:
        if builtins.hasAttr "config" p then {
          inherit (p) plugin;
          config = "lua << EOF\n${p.config}\nEOF";
        } else p) [
        colorscheme  # Is always first.
        lualine
        nvim-cmp
        nvim-dap
        nvim-lspconfig
        nvim-telescope
        nvim-treesitter
        pkgs.vimPlugins.cmp-buffer
        pkgs.vimPlugins.cmp-nvim-lsp
        pkgs.vimPlugins.nvim-web-devicons
        pkgs.vimPlugins.vim-prettier
      ];
      viAlias = true;
      vimAlias = true;
    };

    xdg.configFile."nvim/init.lua".text =
      let
        config = import ./config { inherit pkgs; };
      in
        lib.mkMerge [
          # Extra Lua configuration to be prepended to `init.lua`. Extend the
          # Lua loader to search for our /nix/store/.../?.lua files.
          (lib.mkBefore ''
            package.path = "${config}/?.lua;" .. package.path
          '')
          # Extra Lua configuration to be appended to `init.lua`.
          (lib.mkAfter ''
            vim.g.mapleader = " "
            vim.g.maplocalleader = "\\"
            vim.o.colorcolumn = "80,100"
            vim.o.equalalways = false  -- Disable auto window resize.
            vim.o.expandtab = true     -- Spaces instead of tabs.
            vim.o.list = true          -- Show hidden characters.
            vim.o.shiftwidth = 2       -- # of spaces to use for each (auto)indent.
            vim.o.tabstop = 2          -- # of spaces a <Tab> in the file counts for.

            -- "Zoom" in on a window
            vim.keymap.set("n", "<c-w>z", ":tabedit %<CR>")
            -- Open working directory.
            vim.keymap.set("n", "-", ":Explore<CR>")
          '')
        ];
  };
}