nix-shared/home/develop/emacs.nix

{ config, pkgs, lib, ... }:
let
  snippetsPath = ./emacs/snippets;
  extraSnippetDirs = config.tb.emacs.extraSnippetDirs;
  allSnippetDirs = [ "${snippetsPath}" ] ++ extraSnippetDirs;
  snippetDirsLisp = lib.concatMapStringsSep " " (d: ''"${d}"'') allSnippetDirs;
in
{
  options.tb.emacs.extraSnippetDirs = lib.mkOption {
    type = lib.types.listOf lib.types.path;
    default = ["~/.emacs.d/snippets/"];
    description = "Additional snippet directories for yasnippet";
  };

  config = {
    programs.emacs = {
      enable = true;

      # Optionally provide extra packages not in the configuration file.
      extraPackages = epkgs: with epkgs; [

        # === WEB AND SERVER CONFIGURATION ===
        apache-mode             # Syntax highlighting for Apache config files
        nginx-mode              # Syntax highlighting for Nginx config files

        # === HARDWARE AND EMBEDDED DEVELOPMENT ===
        arduino-mode            # Arduino sketch development support

        # === DOCUMENT PREPARATION ===
        auctex                  # Comprehensive LaTeX editing environment
        pandoc-mode             # Pandoc document converter integration

        # === PROGRAMMING LANGUAGE SUPPORT ===
        basic-mode              # BASIC programming language support
        bison-mode              # Bison parser generator syntax
        cmake-mode              # CMake build system configuration
        coffee-mode             # CoffeeScript programming language
        csharp-mode             # C# programming language
        groovy-mode             # Groovy/Jenkins pipeline scripting
        go-mode                 # Go programming language
        haskell-mode            # Haskell functional programming
        js2-mode                # Enhanced JavaScript editing mode
        lua-mode                # Lua scripting language
        php-mode                # PHP web development
        python-mode             # Python programming language
        scala-mode              # Scala programming language

        # === MARKUP AND DATA FORMATS ===
        csv-mode                # Comma-separated values file editing
        dockerfile-mode         # Docker container definition files
        jinja2-mode             # Jinja2 template engine syntax
        markdown-mode           # Markdown markup language
        nix-mode                # Nix expression language (NixOS configs)
        protobuf-mode           # Protocol Buffers schema definitions
        qml-mode                # Qt QML user interface markup
        yaml-mode               # YAML configuration files
        gnuplot-mode            # Gnuplot script editing and plotting integration

        # === SEARCH AND FILE UTILITIES ===
        rg                      # Ripgrep searcher integration for fast text search
        diredfl                 # Enhanced font-locking for dired mode
        dired-ranger            # File operations with copy/move/paste semantics

        # === TEXT COMPLETION AND PRODUCTIVITY ===
        company                 # Text completion framework
        smex                    # Enhanced M-x command with history

        # === USER INTERFACE ENHANCEMENTS ===
        diminish                # Hide minor modes from the mode line
        smooth-scrolling        # Smoother scrolling experience
        rainbow-delimiters      # Color-code nested parentheses/brackets

        # === ENVIRONMENT AND PROJECT MANAGEMENT ===
        direnv                  # Environment variable management per directory
        projectile              # Project interaction and navigation library

        # === LANGUAGE SERVER PROTOCOL (LSP) ===
        # Modern language support with intelligent features
        eglot                   # Built-in LSP client (simpler alternative to lsp-mode)
        lsp-mode                # Comprehensive Language Server Protocol client
        lsp-java                # Java language server integration
        lsp-metals              # Scala language server (Metals) integration
        eglot-java              # Java support for eglot LSP client
        sbt-mode                # Scala Build Tool integration
        dap-mode                # Debug Adapter Protocol for debugging support

        # === SYNTAX CHECKING ===
        flycheck                # On-the-fly syntax checking framework

        # === VERSION CONTROL ===
        git-link                # Generate links to Git repository web interfaces
        magit                   # Comprehensive Git porcelain for Emacs

        # === TEXT EDITING ENHANCEMENTS ===
        goto-last-change        # Jump to the location of last edit
        iedit                   # Edit multiple occurrences of text simultaneously
        bm                      # Visual bookmarks for quick navigation

        # === CODE FORMATTING AND CLEANUP ===
        web-beautify            # Format and beautify web code (HTML/CSS/JS)
        ethan-wspace            # Automatically clean up whitespace on save

        # === PARENTHESES AND STRUCTURE EDITING ===
        paredit                 # Balanced parentheses editing for Lisp-like languages
        smartparens             # Smart handling of pairs (parentheses, quotes, etc.)

        # === SNIPPETS AND TEMPLATES ===
        yasnippet               # Template system for inserting code snippets
        quelpa-use-package      # Package management for packages not in MELPA

        # === VISUAL THEMES ===
        grandshell-theme        # Dark theme with good contrast
        leuven-theme            # Light theme designed for readability

        # === TREE-SITTER GRAMMARS ===
        # Modern syntax highlighting and parsing using tree-sitter
        treesit-grammars.with-all-grammars  # All available tree-sitter language grammars

        # === TREE-SITTER BASED MODES ===
        # These modes use tree-sitter for better performance and accuracy
        awk-ts-mode             # AWK script editing with tree-sitter
        dart-mode               # Dart programming (Flutter development)
        graphql-ts-mode         # GraphQL query language with tree-sitter
        jq-ts-mode              # jq JSON processor with tree-sitter
        markdown-ts-mode        # Markdown with tree-sitter parsing
        mermaid-ts-mode         # Mermaid diagram syntax with tree-sitter
        scala-ts-mode           # Scala with tree-sitter (alternative to scala-mode)
        swift-ts-mode           # Swift programming with tree-sitter
      ];

      extraConfig = builtins.readFile ./emacs/custom.el + ''

        ;; Yasnippet configuration (generated by nix)
        (use-package yasnippet
          :init
          (setq yas-snippet-dirs '(${snippetDirsLisp}))
          :config
          (yas-reload-all)
          (yas-global-mode 1))
      '';
    };

    # System packages required by various emacs packages
    home.packages = with pkgs; [
      # Search and file utilities
      ripgrep             # Required for rg package
    ];
  };
}