fresh/primitives/grammar/

types.rs

//! Pure grammar registry types without I/O operations.
//!
//! This module contains the `GrammarRegistry` struct and all syntax lookup methods
//! that don't require filesystem access. This enables WASM compatibility and easier testing.

use serde::Deserialize;
use std::collections::HashMap;
use std::path::{Path, PathBuf};
use std::sync::Arc;
use syntect::parsing::{SyntaxDefinition, SyntaxReference, SyntaxSet, SyntaxSetBuilder};

/// Embedded TOML grammar (syntect doesn't include one)
pub const TOML_GRAMMAR: &str = include_str!("../../grammars/toml.sublime-syntax");

/// Embedded Odin grammar (syntect doesn't include one)
/// From: https://github.com/Tetralux/sublime-odin (MIT License)
pub const ODIN_GRAMMAR: &str = include_str!("../../grammars/odin/Odin.sublime-syntax");

/// Embedded Zig grammar (syntect doesn't include one)
pub const ZIG_GRAMMAR: &str = include_str!("../../grammars/zig.sublime-syntax");

/// Embedded Git Rebase Todo grammar for interactive rebase
pub const GIT_REBASE_GRAMMAR: &str = include_str!("../../grammars/git-rebase.sublime-syntax");

/// Embedded Git Commit Message grammar for COMMIT_EDITMSG, MERGE_MSG, etc.
pub const GIT_COMMIT_GRAMMAR: &str = include_str!("../../grammars/git-commit.sublime-syntax");

/// Embedded Gitignore grammar for .gitignore and similar files
pub const GITIGNORE_GRAMMAR: &str = include_str!("../../grammars/gitignore.sublime-syntax");

/// Embedded Git Config grammar for .gitconfig, .gitmodules
pub const GITCONFIG_GRAMMAR: &str = include_str!("../../grammars/gitconfig.sublime-syntax");

/// Embedded Git Attributes grammar for .gitattributes
pub const GITATTRIBUTES_GRAMMAR: &str = include_str!("../../grammars/gitattributes.sublime-syntax");

/// Registry of all available TextMate grammars.
///
/// This struct holds the compiled syntax set and provides lookup methods.
/// It does not perform I/O directly - use `GrammarLoader` for loading grammars.
pub struct GrammarRegistry {
    /// Combined syntax set (built-in + embedded + user grammars)
    syntax_set: Arc<SyntaxSet>,
    /// Extension -> scope name mapping for user grammars (takes priority)
    user_extensions: HashMap<String, String>,
    /// Filename -> scope name mapping for dotfiles and special files
    filename_scopes: HashMap<String, String>,
}

impl GrammarRegistry {
    /// Create a new GrammarRegistry from pre-built components.
    ///
    /// This is typically called by `GrammarLoader` implementations after
    /// loading grammars from various sources.
    pub fn new(
        syntax_set: SyntaxSet,
        user_extensions: HashMap<String, String>,
        filename_scopes: HashMap<String, String>,
    ) -> Self {
        Self {
            syntax_set: Arc::new(syntax_set),
            user_extensions,
            filename_scopes,
        }
    }

    /// Create an empty grammar registry (fast, for tests that don't need syntax highlighting)
    pub fn empty() -> Arc<Self> {
        let mut builder = SyntaxSetBuilder::new();
        builder.add_plain_text_syntax();
        Arc::new(Self {
            syntax_set: Arc::new(builder.build()),
            user_extensions: HashMap::new(),
            filename_scopes: HashMap::new(),
        })
    }

    /// Build the default filename -> scope mappings for dotfiles and special files.
    pub fn build_filename_scopes() -> HashMap<String, String> {
        let mut map = HashMap::new();

        // Shell configuration files -> Bash/Shell script scope
        let shell_scope = "source.shell.bash".to_string();
        for filename in [
            ".zshrc",
            ".zprofile",
            ".zshenv",
            ".zlogin",
            ".zlogout",
            ".bash_aliases",
            // .bashrc and .bash_profile are already recognized by syntect
            // Common shell script files without extensions
            "PKGBUILD",
            "APKBUILD",
        ] {
            map.insert(filename.to_string(), shell_scope.clone());
        }

        // Git rebase todo files
        let git_rebase_scope = "source.git-rebase-todo".to_string();
        map.insert("git-rebase-todo".to_string(), git_rebase_scope);

        // Git commit message files
        let git_commit_scope = "source.git-commit".to_string();
        for filename in ["COMMIT_EDITMSG", "MERGE_MSG", "SQUASH_MSG", "TAG_EDITMSG"] {
            map.insert(filename.to_string(), git_commit_scope.clone());
        }

        // Gitignore and similar files
        let gitignore_scope = "source.gitignore".to_string();
        for filename in [".gitignore", ".dockerignore", ".npmignore", ".hgignore"] {
            map.insert(filename.to_string(), gitignore_scope.clone());
        }

        // Git config files
        let gitconfig_scope = "source.gitconfig".to_string();
        for filename in [".gitconfig", ".gitmodules"] {
            map.insert(filename.to_string(), gitconfig_scope.clone());
        }

        // Git attributes files
        let gitattributes_scope = "source.gitattributes".to_string();
        map.insert(".gitattributes".to_string(), gitattributes_scope);

        map
    }

    /// Add embedded grammars (TOML, Odin, etc.) to a syntax set builder.
    pub fn add_embedded_grammars(builder: &mut SyntaxSetBuilder) {
        // TOML grammar
        match SyntaxDefinition::load_from_str(TOML_GRAMMAR, true, Some("TOML")) {
            Ok(syntax) => {
                builder.add(syntax);
                tracing::debug!("Loaded embedded TOML grammar");
            }
            Err(e) => {
                tracing::warn!("Failed to load embedded TOML grammar: {}", e);
            }
        }

        // Odin grammar
        match SyntaxDefinition::load_from_str(ODIN_GRAMMAR, true, Some("Odin")) {
            Ok(syntax) => {
                builder.add(syntax);
                tracing::debug!("Loaded embedded Odin grammar");
            }
            Err(e) => {
                tracing::warn!("Failed to load embedded Odin grammar: {}", e);
            }
        }

        // Zig grammar
        match SyntaxDefinition::load_from_str(ZIG_GRAMMAR, true, Some("Zig")) {
            Ok(syntax) => {
                builder.add(syntax);
                tracing::debug!("Loaded embedded Zig grammar");
            }
            Err(e) => {
                tracing::warn!("Failed to load embedded Zig grammar: {}", e);
            }
        }

        // Git Rebase Todo grammar
        match SyntaxDefinition::load_from_str(GIT_REBASE_GRAMMAR, true, Some("Git Rebase Todo")) {
            Ok(syntax) => {
                builder.add(syntax);
                tracing::debug!("Loaded embedded Git Rebase Todo grammar");
            }
            Err(e) => {
                tracing::warn!("Failed to load embedded Git Rebase Todo grammar: {}", e);
            }
        }

        // Git Commit Message grammar
        match SyntaxDefinition::load_from_str(GIT_COMMIT_GRAMMAR, true, Some("Git Commit Message"))
        {
            Ok(syntax) => {
                builder.add(syntax);
                tracing::debug!("Loaded embedded Git Commit Message grammar");
            }
            Err(e) => {
                tracing::warn!("Failed to load embedded Git Commit Message grammar: {}", e);
            }
        }

        // Gitignore grammar
        match SyntaxDefinition::load_from_str(GITIGNORE_GRAMMAR, true, Some("Gitignore")) {
            Ok(syntax) => {
                builder.add(syntax);
                tracing::debug!("Loaded embedded Gitignore grammar");
            }
            Err(e) => {
                tracing::warn!("Failed to load embedded Gitignore grammar: {}", e);
            }
        }

        // Git Config grammar
        match SyntaxDefinition::load_from_str(GITCONFIG_GRAMMAR, true, Some("Git Config")) {
            Ok(syntax) => {
                builder.add(syntax);
                tracing::debug!("Loaded embedded Git Config grammar");
            }
            Err(e) => {
                tracing::warn!("Failed to load embedded Git Config grammar: {}", e);
            }
        }

        // Git Attributes grammar
        match SyntaxDefinition::load_from_str(GITATTRIBUTES_GRAMMAR, true, Some("Git Attributes")) {
            Ok(syntax) => {
                builder.add(syntax);
                tracing::debug!("Loaded embedded Git Attributes grammar");
            }
            Err(e) => {
                tracing::warn!("Failed to load embedded Git Attributes grammar: {}", e);
            }
        }
    }

    /// Find syntax for a file by path/extension/filename.
    ///
    /// Checks in order:
    /// 1. User-configured grammar extensions (by scope)
    /// 2. By extension (includes built-in + embedded grammars)
    /// 3. By filename (custom dotfile mappings like .zshrc)
    /// 4. By filename via syntect (handles Makefile, .bashrc, etc.)
    pub fn find_syntax_for_file(&self, path: &Path) -> Option<&SyntaxReference> {
        // Try extension-based lookup first
        if let Some(ext) = path.extension().and_then(|e| e.to_str()) {
            // Check user grammars first (higher priority)
            if let Some(scope) = self.user_extensions.get(ext) {
                if let Some(syntax) = syntect::parsing::Scope::new(scope)
                    .ok()
                    .and_then(|s| self.syntax_set.find_syntax_by_scope(s))
                {
                    return Some(syntax);
                }
            }

            // Try extension lookup (includes embedded grammars like TOML)
            if let Some(syntax) = self.syntax_set.find_syntax_by_extension(ext) {
                return Some(syntax);
            }
        }

        // Try filename-based lookup for dotfiles and special files
        if let Some(filename) = path.file_name().and_then(|n| n.to_str()) {
            if let Some(scope) = self.filename_scopes.get(filename) {
                if let Some(syntax) = syntect::parsing::Scope::new(scope)
                    .ok()
                    .and_then(|s| self.syntax_set.find_syntax_by_scope(s))
                {
                    return Some(syntax);
                }
            }
        }

        // Try syntect's full file detection (handles special filenames like Makefile)
        // This may do I/O for first-line detection, but handles many cases
        if let Ok(Some(syntax)) = self.syntax_set.find_syntax_for_file(path) {
            return Some(syntax);
        }

        None
    }

    /// Find syntax for a file, checking user-configured languages first.
    ///
    /// This method extends `find_syntax_for_file` by first checking the provided
    /// languages configuration for filename and extension matches. This allows
    /// users to configure custom filename patterns (like PKGBUILD for bash) that
    /// will be respected for syntax highlighting.
    ///
    /// Checks in order:
    /// 1. User-configured language filenames from config
    /// 2. User-configured language extensions from config
    /// 3. Falls back to `find_syntax_for_file` for built-in detection
    pub fn find_syntax_for_file_with_languages(
        &self,
        path: &Path,
        languages: &std::collections::HashMap<String, crate::config::LanguageConfig>,
    ) -> Option<&SyntaxReference> {
        // Try filename match from languages config first
        if let Some(filename) = path.file_name().and_then(|f| f.to_str()) {
            for lang_config in languages.values() {
                if lang_config.filenames.iter().any(|f| f == filename) {
                    // Found a match - try to find syntax by grammar name
                    if let Some(syntax) = self.find_syntax_by_name(&lang_config.grammar) {
                        return Some(syntax);
                    }
                    // Also try finding by extension if grammar name didn't work
                    // (some grammars are named differently)
                    if !lang_config.extensions.is_empty() {
                        if let Some(ext) = lang_config.extensions.first() {
                            if let Some(syntax) = self.syntax_set.find_syntax_by_extension(ext) {
                                return Some(syntax);
                            }
                        }
                    }
                }
            }
        }

        // Try extension match from languages config
        if let Some(extension) = path.extension().and_then(|e| e.to_str()) {
            for lang_config in languages.values() {
                if lang_config.extensions.iter().any(|ext| ext == extension) {
                    // Found a match - try to find syntax by grammar name
                    if let Some(syntax) = self.find_syntax_by_name(&lang_config.grammar) {
                        return Some(syntax);
                    }
                }
            }
        }

        // Fall back to built-in detection
        self.find_syntax_for_file(path)
    }

    /// Find syntax by first line content (shebang, mode line, etc.)
    ///
    /// Use this when you have the file content but path-based detection failed.
    pub fn find_syntax_by_first_line(&self, first_line: &str) -> Option<&SyntaxReference> {
        self.syntax_set.find_syntax_by_first_line(first_line)
    }

    /// Find syntax by scope name
    pub fn find_syntax_by_scope(&self, scope: &str) -> Option<&SyntaxReference> {
        let scope = syntect::parsing::Scope::new(scope).ok()?;
        self.syntax_set.find_syntax_by_scope(scope)
    }

    /// Find syntax by name (case-insensitive)
    ///
    /// This allows config files to use lowercase grammar names like "go" while
    /// matching syntect's actual names like "Go".
    pub fn find_syntax_by_name(&self, name: &str) -> Option<&SyntaxReference> {
        // Try exact match first
        if let Some(syntax) = self.syntax_set.find_syntax_by_name(name) {
            return Some(syntax);
        }
        // Fall back to case-insensitive match
        let name_lower = name.to_lowercase();
        self.syntax_set
            .syntaxes()
            .iter()
            .find(|s| s.name.to_lowercase() == name_lower)
    }

    /// Get the underlying syntax set
    pub fn syntax_set(&self) -> &Arc<SyntaxSet> {
        &self.syntax_set
    }

    /// Get a clone of the Arc for sharing
    pub fn syntax_set_arc(&self) -> Arc<SyntaxSet> {
        Arc::clone(&self.syntax_set)
    }

    /// List all available syntax names
    pub fn available_syntaxes(&self) -> Vec<&str> {
        self.syntax_set
            .syntaxes()
            .iter()
            .map(|s| s.name.as_str())
            .collect()
    }

    /// Check if a syntax is available for an extension
    pub fn has_syntax_for_extension(&self, ext: &str) -> bool {
        if self.user_extensions.contains_key(ext) {
            return true;
        }

        // Check built-in syntaxes
        let dummy_path = PathBuf::from(format!("file.{}", ext));
        self.syntax_set
            .find_syntax_for_file(&dummy_path)
            .ok()
            .flatten()
            .is_some()
    }

    /// Get the user extensions mapping (extension -> scope name)
    pub fn user_extensions(&self) -> &HashMap<String, String> {
        &self.user_extensions
    }

    /// Get the filename scopes mapping (filename -> scope name)
    pub fn filename_scopes(&self) -> &HashMap<String, String> {
        &self.filename_scopes
    }
}

impl Default for GrammarRegistry {
    fn default() -> Self {
        // Create with defaults and embedded grammars only (no user grammars)
        let defaults = SyntaxSet::load_defaults_newlines();
        let mut builder = defaults.into_builder();
        Self::add_embedded_grammars(&mut builder);
        let syntax_set = builder.build();
        let filename_scopes = Self::build_filename_scopes();

        Self::new(syntax_set, HashMap::new(), filename_scopes)
    }
}

// VSCode package.json structures for parsing grammar manifests

#[derive(Debug, Deserialize)]
pub struct PackageManifest {
    #[serde(default)]
    pub contributes: Option<Contributes>,
}

#[derive(Debug, Deserialize, Default)]
pub struct Contributes {
    #[serde(default)]
    pub languages: Vec<LanguageContribution>,
    #[serde(default)]
    pub grammars: Vec<GrammarContribution>,
}

#[derive(Debug, Deserialize)]
pub struct LanguageContribution {
    pub id: String,
    #[serde(default)]
    pub extensions: Vec<String>,
}

#[derive(Debug, Deserialize)]
pub struct GrammarContribution {
    pub language: String,
    #[serde(rename = "scopeName")]
    pub scope_name: String,
    pub path: String,
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_empty_registry() {
        let registry = GrammarRegistry::empty();
        // Should have at least plain text
        assert!(!registry.available_syntaxes().is_empty());
    }

    #[test]
    fn test_default_registry() {
        let registry = GrammarRegistry::default();
        // Should have built-in syntaxes
        assert!(!registry.available_syntaxes().is_empty());
    }

    #[test]
    fn test_find_syntax_for_common_extensions() {
        let registry = GrammarRegistry::default();

        // Test common extensions that syntect should support
        let test_cases = [
            ("test.py", true),
            ("test.rs", true),
            ("test.js", true),
            ("test.json", true),
            ("test.md", true),
            ("test.html", true),
            ("test.css", true),
            ("test.unknown_extension_xyz", false),
        ];

        for (filename, should_exist) in test_cases {
            let path = Path::new(filename);
            let result = registry.find_syntax_for_file(path);
            assert_eq!(
                result.is_some(),
                should_exist,
                "Expected {:?} for {}",
                should_exist,
                filename
            );
        }
    }

    #[test]
    fn test_syntax_set_arc() {
        let registry = GrammarRegistry::default();
        let arc1 = registry.syntax_set_arc();
        let arc2 = registry.syntax_set_arc();
        // Both should point to the same data
        assert!(Arc::ptr_eq(&arc1, &arc2));
    }

    #[test]
    fn test_shell_dotfiles_detection() {
        let registry = GrammarRegistry::default();

        // All these should be detected as shell scripts
        let shell_files = [".zshrc", ".zprofile", ".zshenv", ".bash_aliases"];

        for filename in shell_files {
            let path = Path::new(filename);
            let result = registry.find_syntax_for_file(path);
            assert!(
                result.is_some(),
                "{} should be detected as a syntax",
                filename
            );
            let syntax = result.unwrap();
            // Should be detected as Bash/Shell
            assert!(
                syntax.name.to_lowercase().contains("bash")
                    || syntax.name.to_lowercase().contains("shell"),
                "{} should be detected as shell/bash, got: {}",
                filename,
                syntax.name
            );
        }
    }

    #[test]
    fn test_pkgbuild_detection() {
        let registry = GrammarRegistry::default();

        // PKGBUILD and APKBUILD should be detected as shell scripts
        for filename in ["PKGBUILD", "APKBUILD"] {
            let path = Path::new(filename);
            let result = registry.find_syntax_for_file(path);
            assert!(
                result.is_some(),
                "{} should be detected as a syntax",
                filename
            );
            let syntax = result.unwrap();
            // Should be detected as Bash/Shell
            assert!(
                syntax.name.to_lowercase().contains("bash")
                    || syntax.name.to_lowercase().contains("shell"),
                "{} should be detected as shell/bash, got: {}",
                filename,
                syntax.name
            );
        }
    }
}