alef-core 0.2.0

use serde::{Deserialize, Serialize};
use std::collections::HashMap;
use std::path::PathBuf;

pub mod dto;
pub mod e2e;
pub mod extras;
pub mod languages;
pub mod output;

// Re-exports for backward compatibility — all types were previously flat in config.rs.
pub use dto::{
    CsharpDtoStyle, DtoConfig, ElixirDtoStyle, GoDtoStyle, JavaDtoStyle, NodeDtoStyle, PhpDtoStyle, PythonDtoStyle,
    RDtoStyle, RubyDtoStyle,
};
pub use e2e::E2eConfig;
pub use extras::{AdapterConfig, AdapterParam, AdapterPattern, Language};
pub use languages::{
    CSharpConfig, CustomModulesConfig, CustomRegistration, CustomRegistrationsConfig, ElixirConfig, FfiConfig,
    GoConfig, JavaConfig, NodeConfig, PhpConfig, PythonConfig, RConfig, RubyConfig, StubsConfig, WasmConfig,
};
pub use output::{
    ExcludeConfig, IncludeConfig, LintConfig, OutputConfig, ReadmeConfig, ScaffoldConfig, SyncConfig, TestConfig,
    TextReplacement,
};

/// Root configuration from alef.toml.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct AlefConfig {
    #[serde(rename = "crate")]
    pub crate_config: CrateConfig,
    pub languages: Vec<Language>,
    #[serde(default)]
    pub exclude: ExcludeConfig,
    #[serde(default)]
    pub include: IncludeConfig,
    #[serde(default)]
    pub output: OutputConfig,
    #[serde(default)]
    pub python: Option<PythonConfig>,
    #[serde(default)]
    pub node: Option<NodeConfig>,
    #[serde(default)]
    pub ruby: Option<RubyConfig>,
    #[serde(default)]
    pub php: Option<PhpConfig>,
    #[serde(default)]
    pub elixir: Option<ElixirConfig>,
    #[serde(default)]
    pub wasm: Option<WasmConfig>,
    #[serde(default)]
    pub ffi: Option<FfiConfig>,
    #[serde(default)]
    pub go: Option<GoConfig>,
    #[serde(default)]
    pub java: Option<JavaConfig>,
    #[serde(default)]
    pub csharp: Option<CSharpConfig>,
    #[serde(default)]
    pub r: Option<RConfig>,
    #[serde(default)]
    pub scaffold: Option<ScaffoldConfig>,
    #[serde(default)]
    pub readme: Option<ReadmeConfig>,
    #[serde(default)]
    pub lint: Option<HashMap<String, LintConfig>>,
    #[serde(default)]
    pub test: Option<HashMap<String, TestConfig>>,
    #[serde(default)]
    pub custom_files: Option<HashMap<String, Vec<PathBuf>>>,
    #[serde(default)]
    pub adapters: Vec<AdapterConfig>,
    #[serde(default)]
    pub custom_modules: CustomModulesConfig,
    #[serde(default)]
    pub custom_registrations: CustomRegistrationsConfig,
    #[serde(default)]
    pub sync: Option<SyncConfig>,
    /// Declare opaque types from external crates that alef can't extract.
    /// Map of type name → Rust path (e.g., "Tree" = "tree_sitter_language_pack::Tree").
    /// These get opaque wrapper structs in all backends.
    #[serde(default)]
    pub opaque_types: HashMap<String, String>,
    /// Controls which generation passes alef runs (all default to true).
    #[serde(default)]
    pub generate: GenerateConfig,
    /// Per-language overrides for generate flags (key = language name, e.g., "python").
    #[serde(default)]
    pub generate_overrides: HashMap<String, GenerateConfig>,
    /// Per-language DTO/type generation style (dataclass vs TypedDict, zod vs interface, etc.).
    #[serde(default)]
    pub dto: DtoConfig,
    /// E2E test generation configuration.
    #[serde(default)]
    pub e2e: Option<E2eConfig>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct CrateConfig {
    pub name: String,
    pub sources: Vec<PathBuf>,
    #[serde(default = "default_version_from")]
    pub version_from: String,
    #[serde(default)]
    pub core_import: Option<String>,
    /// Optional workspace root path for resolving `pub use` re-exports from sibling crates.
    #[serde(default)]
    pub workspace_root: Option<PathBuf>,
    /// When true, skip adding `use {core_import};` to generated bindings.
    #[serde(default)]
    pub skip_core_import: bool,
    /// Maps extracted rust_path prefixes to actual import paths in binding crates.
    /// Example: { "spikard" = "spikard_http" } rewrites "spikard::ServerConfig" to "spikard_http::ServerConfig"
    #[serde(default)]
    pub path_mappings: HashMap<String, String>,
}

fn default_version_from() -> String {
    "Cargo.toml".to_string()
}

fn default_true() -> bool {
    true
}

/// Controls which generation passes alef runs.
/// All flags default to `true`; set to `false` to skip a pass.
/// Can be overridden per-language via `[generate_overrides.<lang>]`.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct GenerateConfig {
    /// Generate low-level struct wrappers, From impls, module init (default: true)
    #[serde(default = "default_true")]
    pub bindings: bool,
    /// Generate error type hierarchies from thiserror enums (default: true)
    #[serde(default = "default_true")]
    pub errors: bool,
    /// Generate config builder constructors from Default types (default: true)
    #[serde(default = "default_true")]
    pub configs: bool,
    /// Generate async/sync function pairs with runtime management (default: true)
    #[serde(default = "default_true")]
    pub async_wrappers: bool,
    /// Generate recursive type marshaling helpers (default: true)
    #[serde(default = "default_true")]
    pub type_conversions: bool,
    /// Generate package manifests (pyproject.toml, package.json, etc.) (default: true)
    #[serde(default = "default_true")]
    pub package_metadata: bool,
    /// Generate idiomatic public API wrappers (default: true)
    #[serde(default = "default_true")]
    pub public_api: bool,
}

impl Default for GenerateConfig {
    fn default() -> Self {
        Self {
            bindings: true,
            errors: true,
            configs: true,
            async_wrappers: true,
            type_conversions: true,
            package_metadata: true,
            public_api: true,
        }
    }
}

// ---------------------------------------------------------------------------
// Shared config resolution helpers
// ---------------------------------------------------------------------------

impl AlefConfig {
    /// Get the core crate import path (e.g., "liter_llm"). Used by codegen to call into the core crate.
    pub fn core_import(&self) -> String {
        self.crate_config
            .core_import
            .clone()
            .unwrap_or_else(|| self.crate_config.name.replace('-', "_"))
    }

    /// Get the FFI prefix (e.g., "kreuzberg"). Used by FFI, Go, Java, C# backends.
    pub fn ffi_prefix(&self) -> String {
        self.ffi
            .as_ref()
            .and_then(|f| f.prefix.as_ref())
            .cloned()
            .unwrap_or_else(|| self.crate_config.name.replace('-', "_"))
    }

    /// Get the FFI native library name (for Go cgo, Java Panama, C# P/Invoke).
    ///
    /// Resolution order:
    /// 1. `[ffi] lib_name` explicit override
    /// 2. Directory name of `output.ffi` path with hyphens replaced by underscores
    ///    (e.g. `crates/html-to-markdown-ffi/src/` → `html_to_markdown_ffi`)
    /// 3. `{ffi_prefix}_ffi` fallback
    pub fn ffi_lib_name(&self) -> String {
        // 1. Explicit override in [ffi] section.
        if let Some(name) = self.ffi.as_ref().and_then(|f| f.lib_name.as_ref()) {
            return name.clone();
        }

        // 2. Derive from output.ffi path: take the last meaningful directory component
        //    (skip trailing "src" or similar), then replace hyphens with underscores.
        if let Some(ffi_path) = self.output.ffi.as_ref() {
            let path = std::path::Path::new(ffi_path);
            // Walk components from the end to find the crate directory name.
            // Skip components like "src" that are inside the crate dir.
            let components: Vec<_> = path
                .components()
                .filter_map(|c| {
                    if let std::path::Component::Normal(s) = c {
                        s.to_str()
                    } else {
                        None
                    }
                })
                .collect();
            // The crate name is typically the last component that looks like a crate dir
            // (i.e. not "src", "lib", or similar). Search from the end.
            let crate_dir = components
                .iter()
                .rev()
                .find(|&&s| s != "src" && s != "lib" && s != "include")
                .copied();
            if let Some(dir) = crate_dir {
                return dir.replace('-', "_");
            }
        }

        // 3. Default fallback.
        format!("{}_ffi", self.ffi_prefix())
    }

    /// Get the FFI header name.
    pub fn ffi_header_name(&self) -> String {
        self.ffi
            .as_ref()
            .and_then(|f| f.header_name.as_ref())
            .cloned()
            .unwrap_or_else(|| format!("{}.h", self.ffi_prefix()))
    }

    /// Get the Python module name.
    pub fn python_module_name(&self) -> String {
        self.python
            .as_ref()
            .and_then(|p| p.module_name.as_ref())
            .cloned()
            .unwrap_or_else(|| format!("_{}", self.crate_config.name.replace('-', "_")))
    }

    /// Get the Node package name.
    pub fn node_package_name(&self) -> String {
        self.node
            .as_ref()
            .and_then(|n| n.package_name.as_ref())
            .cloned()
            .unwrap_or_else(|| self.crate_config.name.clone())
    }

    /// Get the Ruby gem name.
    pub fn ruby_gem_name(&self) -> String {
        self.ruby
            .as_ref()
            .and_then(|r| r.gem_name.as_ref())
            .cloned()
            .unwrap_or_else(|| self.crate_config.name.replace('-', "_"))
    }

    /// Get the PHP extension name.
    pub fn php_extension_name(&self) -> String {
        self.php
            .as_ref()
            .and_then(|p| p.extension_name.as_ref())
            .cloned()
            .unwrap_or_else(|| self.crate_config.name.replace('-', "_"))
    }

    /// Get the Elixir app name.
    pub fn elixir_app_name(&self) -> String {
        self.elixir
            .as_ref()
            .and_then(|e| e.app_name.as_ref())
            .cloned()
            .unwrap_or_else(|| self.crate_config.name.replace('-', "_"))
    }

    /// Get the Go module path.
    pub fn go_module(&self) -> String {
        self.go
            .as_ref()
            .and_then(|g| g.module.as_ref())
            .cloned()
            .unwrap_or_else(|| format!("github.com/kreuzberg-dev/{}", self.crate_config.name))
    }

    /// Get the Java package name.
    pub fn java_package(&self) -> String {
        self.java
            .as_ref()
            .and_then(|j| j.package.as_ref())
            .cloned()
            .unwrap_or_else(|| "dev.kreuzberg".to_string())
    }

    /// Get the C# namespace.
    pub fn csharp_namespace(&self) -> String {
        self.csharp
            .as_ref()
            .and_then(|c| c.namespace.as_ref())
            .cloned()
            .unwrap_or_else(|| {
                use heck::ToPascalCase;
                self.crate_config.name.to_pascal_case()
            })
    }

    /// Get the R package name.
    pub fn r_package_name(&self) -> String {
        self.r
            .as_ref()
            .and_then(|r| r.package_name.as_ref())
            .cloned()
            .unwrap_or_else(|| self.crate_config.name.clone())
    }

    /// Rewrite a rust_path using path_mappings.
    /// Matches the longest prefix first.
    pub fn rewrite_path(&self, rust_path: &str) -> String {
        // Sort mappings by key length descending (longest prefix first)
        let mut mappings: Vec<_> = self.crate_config.path_mappings.iter().collect();
        mappings.sort_by(|a, b| b.0.len().cmp(&a.0.len()));

        for (from, to) in &mappings {
            if rust_path.starts_with(from.as_str()) {
                return format!("{}{}", to, &rust_path[from.len()..]);
            }
        }
        rust_path.to_string()
    }
}

/// Helper function to resolve output directory path from config.
/// Replaces {name} placeholder with the crate name.
pub fn resolve_output_dir(config_path: Option<&PathBuf>, crate_name: &str, default: &str) -> String {
    config_path
        .map(|p| p.to_string_lossy().replace("{name}", crate_name))
        .unwrap_or_else(|| default.replace("{name}", crate_name))
}

/// Detect whether `serde` and `serde_json` are available in a binding crate's Cargo.toml.
///
/// `output_dir` is the generated source directory (e.g., `crates/spikard-py/src/`).
/// The function walks up to find the crate's Cargo.toml and checks its `[dependencies]`
/// for both `serde` and `serde_json`.
pub fn detect_serde_available(output_dir: &str) -> bool {
    let src_path = std::path::Path::new(output_dir);
    // Walk up from the output dir to find Cargo.toml (usually output_dir is `crates/foo/src/`)
    let mut dir = src_path;
    loop {
        let cargo_toml = dir.join("Cargo.toml");
        if cargo_toml.exists() {
            return cargo_toml_has_serde(&cargo_toml);
        }
        match dir.parent() {
            Some(parent) if !parent.as_os_str().is_empty() => dir = parent,
            _ => break,
        }
    }
    false
}

/// Check if a Cargo.toml has both `serde` (with derive feature) and `serde_json` in its dependencies.
///
/// The `serde::Serialize` derive macro requires `serde` as a direct dependency with the `derive`
/// feature enabled. Having only `serde_json` is not sufficient since it only pulls in `serde`
/// transitively without the derive proc-macro.
fn cargo_toml_has_serde(path: &std::path::Path) -> bool {
    let content = match std::fs::read_to_string(path) {
        Ok(c) => c,
        Err(_) => return false,
    };

    let has_serde_json = content.contains("serde_json");
    // Check for `serde` as a direct dependency (not just serde_json).
    // Must match "serde" as a TOML key, not as a substring of "serde_json".
    // Valid patterns: `serde = `, `serde.`, `[dependencies.serde]`
    let has_serde_dep = content.lines().any(|line| {
        let trimmed = line.trim();
        // Match `serde = ...` or `serde.workspace = true` etc., but not `serde_json`
        trimmed.starts_with("serde ")
            || trimmed.starts_with("serde=")
            || trimmed.starts_with("serde.")
            || trimmed == "[dependencies.serde]"
    });

    has_serde_json && has_serde_dep
}