amberjs 1.17.0

// 预编译模块缓存系统
// 预编译常用 Node.js 模块并缓存字节码，提升执行速度

use anyhow::{Context, Result, anyhow};
use crate::code_cache::{BytecodeCache, CacheConfig};
use serde::{Deserialize, Serialize};
use std::collections::{BTreeMap, HashMap};
use std::sync::{Arc, Mutex};
use std::time::{Duration, Instant};
use std::time::SystemTime;
use std::path::PathBuf;
use std::hash::{Hash, Hasher, DefaultHasher};

/// 预编译模块缓存统计
#[derive(Debug, Clone, Default)]
pub struct PrecompiledCacheStats {
    pub total_modules: usize,
    pub cached_modules: usize,
    pub cache_hits: u64,
    pub cache_misses: u64,
    pub average_compile_time_ms: f64,
    pub total_compile_time_ms: u64,
}
/// 预编译模块条目
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct PrecompiledModuleEntry {
    pub module_name: String,
    pub bytecode: Vec<u8>,
    pub source_hash: String,
    pub compile_time_ms: u64,
    pub created_at: std::time::SystemTime,
}
/// 预编译模块缓存
pub struct PrecompiledModuleCache {
    /// 缓存目录
    cache_dir: PathBuf,
    /// 内存缓存的模块
    modules: Arc<Mutex<HashMap<String, PrecompiledModuleEntry>>>,
    /// 统计信息
    stats: Arc<Mutex<PrecompiledCacheStats>>,
    /// V8 字节码缓存
    #[allow(dead_code)]
    bytecode_cache: Arc<BytecodeCache>,
}
impl PrecompiledModuleCache {
    /// 创建新的预编译模块缓存
    pub fn new() -> Result<Self> {
        let cache_dir: _ = std::env::temp_dir().join("amberjs_precompiled_cache");
        Self::new_with_path(cache_dir)
    }
    /// 使用指定路径创建预编译模块缓存
    pub fn new_with_path(cache_dir: PathBuf) -> Result<Self> {
        // 创建缓存目录
        fs::create_dir_all(&cache_dir)
            .context(format!("Failed to create cache directory: {:?}", cache_dir))?;
        let cache_config: _ = CacheConfig::default();
        Ok(Self {
            cache_dir,
            modules: Arc::new(Mutex::new(HashMap::new()))
            stats: Arc::new(Mutex::new(PrecompiledCacheStats::default()))
            bytecode_cache: Arc::new(Mutex::new(BytecodeCache::new(cache_config)))
        })
    }
    /// 从磁盘加载预编译模块缓存
    pub fn load_from_path(cache_dir: PathBuf) -> Result<Self> {
        let mut cache = PrecompiledModuleCache::new_with_path(cache_dir)?;
        // 加载已缓存的模块
        cache.load_from_disk()?;
        Ok(cache)
    }
    /// 预编译所有内置模块
    pub fn precompile_builtin_modules(&self) -> Result<()> {
        let builtin_modules: _ = Self::get_builtin_modules_list();
        for module in &builtin_modules {
            if !self.is_module_cached(module) {
                let source: _ = self.get_builtin_module_source(module)?;
                self.cache_module(module, &source)?;
            }
        }
        Ok(())
    }
    /// 获取内置模块列表
    pub fn get_builtin_modules_list() -> Vec<&'static str> {
        vec![
            "console",
            "process",
            "path",
            "fs",
            "os",
            "util",
            "events",
            "stream",
            "buffer",
            "crypto",
        ]
    }
    /// 获取内置模块源码
    fn get_builtin_module_source(&self, module_name: &str) -> Result<String> {
        match module_name {
            "console" => Ok(Self::builtin_console_module()),
            "process" => Ok(Self::builtin_process_module()),
            "path" => Ok(Self::builtin_path_module()),
            "fs" => Ok(Self::builtin_fs_module()),
            "os" => Ok(Self::builtin_os_module()),
            "util" => Ok(Self::builtin_util_module()),
            "events" => Ok(Self::builtin_events_module()),
            "stream" => Ok(Self::builtin_stream_module()),
            "buffer" => Ok(Self::builtin_buffer_module()),
            "crypto" => Ok(Self::builtin_crypto_module()),
            _ => Err(anyhow!("Unknown builtin module: {}", module_name)),
        }
    }
    /// 缓存模块
    pub fn cache_module(&self, module_name: &str, source_code: &str) -> Result<()> {
        let start_time: _ = Instant::now();
        // 计算源码哈希
        let source_hash: _ = self.calculate_source_hash(source_code);
        // 编译源码
        let bytecode: _ = self.compile_to_bytecode(source_code)?;
        let compile_time: _ = start_time.elapsed();
        let entry: _ = PrecompiledModuleEntry {
            module_name: module_name.to_string(),
            bytecode,
            source_hash,
            compile_time_ms: compile_time.as_millis() as u64,
            created_at: std::time::SystemTime::now(),
        };
        // 保存到内存缓存
        {
            let mut modules = self.modules.lock().unwrap();
            modules.insert(module_name.to_string(), entry.clone());
        }
        // 持久化到磁盘
        self.persist_module(module_name, &entry)?;
        // 更新统计
        self.update_stats(compile_time);
        Ok(())
    }
    /// 检查模块是否已缓存
    pub fn is_module_cached(&self, module_name: &str) -> bool {
        let modules: _ = self.modules.lock().unwrap();
        modules.contains_key(module_name)
    }
    /// 获取预编译字节码
    pub fn get_precompiled_bytecode(&self, module_name: &str) -> Option<Vec<u8> {
        let modules: _ = self.modules.lock().unwrap();
        if let Some(entry) = modules.get(module_name) {
            // 更新命中统计
            {
                let mut stats = self.stats.lock().unwrap();
                stats.cache_hits += 1;
            }
            Some(entry.bytecode.clone())
        } else {
            // 更新未命中统计
            {
                let mut stats = self.stats.lock().unwrap();
                stats.cache_misses += 1;
            }
            None
        }
    }
    /// 使模块缓存失效
    pub fn invalidate_module(&self, module_name: &str) -> Result<()> {
        // 从内存缓存中移除
        {
            let mut modules = self.modules.lock().unwrap();
            modules.remove(module_name);
        }
        // 从磁盘移除
        let module_file: _ = self.cache_dir.join(format!("{}.bin", module_name));
        if module_file.exists() {
            fs::remove_file(&module_file)
                .context(format!("Failed to remove cached module: {}", module_name))?;
        }
        Ok(())
    }
    /// 获取缓存统计
    pub fn get_stats(&self) -> PrecompiledCacheStats {
        let modules: _ = self.modules.lock().unwrap();
        let stats: _ = self.stats.lock().unwrap();
        PrecompiledCacheStats {
            total_modules: modules.len(),
            cached_modules: modules.len(),
            cache_hits: stats.cache_hits,
            cache_misses: stats.cache_misses,
            average_compile_time_ms: if stats.cache_hits + stats.cache_misses > 0 {
                stats.total_compile_time_ms as f64 / (stats.cache_hits + stats.cache_misses) as f64
            } else {
                0.0
            },
            total_compile_time_ms: stats.total_compile_time_ms,
        }
    }
    /// 计算源码哈希
    fn calculate_source_hash(&self, source: &str) -> String {
        let mut hasher = DefaultHasher::new();
        source.hash(&mut hasher);
        format!("{:x}", hasher.finish())
    }
    /// 编译源码为字节码
    fn compile_to_bytecode(&self, source: &str) -> Result<Vec<u8> {
        // 这里我们需要集成 V8 编译逻辑
        // 暂时返回模拟字节码
        let bytecode: _ = source.as_bytes().to_vec();
        Ok(bytecode)
    }
    /// 更新统计信息
    fn update_stats(&self, compile_time: Duration) {
        let mut stats = self.stats.lock().unwrap();
        stats.total_compile_time_ms += compile_time.as_millis() as u64;
    }
    /// 持久化模块到磁盘
    fn persist_module(&self, module_name: &str, entry: &PrecompiledModuleEntry) -> Result<()> {
        let module_file: _ = self.cache_dir.join(format!("{}.bin", module_name));
        let serialized: _ = bincode::serialize(entry)
            .context(format!("Failed to serialize module: {}", module_name))?;
        fs::write(&module_file, serialized)
            .context(format!("Failed to write cached module: {:?}", module_file))?;
        Ok(())
    }
    /// 从磁盘加载缓存
    fn load_from_disk(&mut self) -> Result<()> {
        if !self.cache_dir.exists() {
            return Ok(());
        }
        let entries: _ = fs::read_dir(&self.cache_dir)
            .context(format!("Failed to read cache directory: {:?}", self.cache_dir))?;
        for entry in entries {
            let entry: _ = entry?;
            let path: _ = entry.path();
            if path.extension().map_or(false, |ext| ext == "bin") {
                let serialized: _ = fs::read(&path)
                    .context(format!("Failed to read cached file: {:?}", path))?;
                let module_entry: PrecompiledModuleEntry = bincode::deserialize(&serialized)
                    .context(format!("Failed to deserialize module: {:?}", path))?;
                let module_name: _ = module_entry.module_name.clone();
                let mut modules = self.modules.lock().unwrap();
                modules.insert(module_name, module_entry);
            }
        }
        Ok(())
    }
    // ========== 内置模块源码实现 ==========
    fn builtin_console_module() -> String {
        r#"
        const console = {
            log: (...args) => {
                // 将日志输出到 V8
            },
            error: (...args) => {
                // 将错误输出到 stderr
            },
            warn: (...args) => {
                // 将警告输出到 stderr
            },
            info: (...args) => {
                // 将信息输出到 stdout
            },
            debug: (...args) => {
                // 调试输出
            }
        };
        module.exports = console;
        "#
        .to_string()
    }
    fn builtin_process_module() -> String {
        r#"
        const process = {
            version: 'v18.0.0',
            argv: [],
            env: {},
            cwd: () => '/',
            nextTick: (fn) => {
                // 异步执行
                setTimeout(fn, 0);
            }
        };
        module.exports = process;
        "#
        .to_string()
    }
    fn builtin_path_module() -> String {
        r#"
        const path = {
            join: (...paths) => {
                return paths.join('/');
            },
            resolve: (...paths) => {
                return '/' + paths.join('/');
            },
            dirname: (p) => {
                return p.substring(0, p.lastIndexOf('/'));
            },
            basename: (p) => {
                const parts = p.split('/');
                return parts[parts.length - 1];
            }
        };
        module.exports = path;
        "#
        .to_string()
    }
    fn builtin_fs_module() -> String {
        r#"
        const fs = {
            readFile: (path, callback) => {
                // 异步文件读取
            },
            writeFile: (path, data, callback) => {
                // 异步文件写入
            }
        };
        module.exports = fs;
        "#
        .to_string()
    }
    fn builtin_os_module() -> String {
        r#"
        const os = {
            platform: () => process.platform,
            arch: () => process.arch,
            cpus: () => []
        };
        module.exports = os;
        "#
        .to_string()
    }
    fn builtin_util_module() -> String {
        r#"
        const util = {
            format: (format, ...args) => {
                return format.replace(/%[sdif]/g, (match) => {
                    return args.shift() || match;
                });
            },
            inspect: (obj) => {
                return JSON.stringify(obj);
            }
        };
        module.exports = util;
        "#
        .to_string()
    }
    fn builtin_events_module() -> String {
        r#"
        class EventEmitter {
            constructor() {
                this.events = {};
            }
            on(event, listener) {
                if (!this.events[event]) {
                    this.events[event] = [];
                }
                this.events[event].push(listener);
            }
            emit(event, ...args) {
                if (this.events[event]) {
                    this.events[event].forEach(fn => fn(...args));
                }
            }
        }
        module.exports = EventEmitter;
        "#
        .to_string()
    }
    fn builtin_stream_module() -> String {
        r#"
        const stream = {
            Readable: class {
                constructor() {}
                on(event, listener) {}
                read() {}
            },
            Writable: class {
                constructor() {}
                on(event, listener) {}
                write(data) {}
            }
        };
        module.exports = stream;
        "#
        .to_string()
    }
    fn builtin_buffer_module() -> String {
        r#"
        class Buffer {
            constructor(data) {
                this.data = data;
            }
            toString() {
                return String(this.data);
            }
        }
        module.exports = Buffer;
        "#
        .to_string()
    }
    fn builtin_crypto_module() -> String {
        r#"
        const crypto = {
            createHash: (algorithm) => {
                return {
                    update: (data) => this,
                    digest: (encoding) => ''
                };
            }
        };
        module.exports = crypto;
        "#
        .to_string()
    }
}
#[cfg(test)]
mod tests {
    #[test]
    fn test_cache_creation() {
        let cache: _ = PrecompiledModuleCache::new();
        assert!(cache.is_ok());
    }
    #[test]
    fn test_builtin_modules_list() {
        let modules: _ = PrecompiledModuleCache::get_builtin_modules_list();
        assert!(modules.len() > 0);
        assert!(modules.contains(&"console"));
        assert!(modules.contains(&"process"));
    }
    #[test]
    fn test_module_caching() {
        let cache: _ = PrecompiledModuleCache::new().unwrap();
        let source: _ = "module.exports = { test: true };";
        let result: _ = cache.cache_module("test_module", source);
        assert!(result.is_ok());
        assert!(cache.is_module_cached("test_module"));
    }
    #[test]
    fn test_cache_stats() {
        let cache: _ = PrecompiledModuleCache::new().unwrap();
        cache.precompile_builtin_modules().unwrap();
        let stats: _ = cache.get_stats();
        assert!(stats.cached_modules > 0);
    }
}