use sha2::{Digest, Sha256};
use std::collections::HashMap;
use std::fs;
use std::io::Result;
use std::path::{Path, PathBuf};
use std::process::Command;

// 支持的文件类型
const SUPPORTED_EXTENSIONS: [&str; 3] = ["html", "js", "css"];

fn check_and_install_deps() -> Result<()> {
    let scripts_dir = Path::new("scripts");
    let node_modules = scripts_dir.join("node_modules");

    if !node_modules.exists() {
        println!("cargo:warning=Installing minifier dependencies...");
        let status = Command::new("npm")
            .current_dir(scripts_dir)
            .arg("install")
            .status()?;

        if !status.success() {
            panic!("Failed to install npm dependencies");
        }
        println!("cargo:warning=Dependencies installed successfully");
    }
    Ok(())
}

fn get_files_hash() -> Result<HashMap<PathBuf, String>> {
    let mut file_hashes = HashMap::new();
    let static_dir = Path::new("static");

    if static_dir.exists() {
        for entry in fs::read_dir(static_dir)? {
            let entry = entry?;
            let path = entry.path();

            // 检查是否是支持的文件类型，且不是已经压缩的文件
            if let Some(ext) = path.extension().and_then(|e| e.to_str()) {
                if SUPPORTED_EXTENSIONS.contains(&ext) && !path.to_string_lossy().contains(".min.")
                {
                    let content = fs::read(&path)?;
                    let mut hasher = Sha256::new();
                    hasher.update(&content);
                    let hash = format!("{:x}", hasher.finalize());
                    file_hashes.insert(path, hash);
                }
            }
        }
    }

    Ok(file_hashes)
}

fn load_saved_hashes() -> Result<HashMap<PathBuf, String>> {
    let hash_file = Path::new("scripts/.asset-hashes.json");
    if hash_file.exists() {
        let content = fs::read_to_string(hash_file)?;
        let hash_map: HashMap<String, String> = serde_json::from_str(&content)?;
        Ok(hash_map
            .into_iter()
            .map(|(k, v)| (PathBuf::from(k), v))
            .collect())
    } else {
        Ok(HashMap::new())
    }
}

fn save_hashes(hashes: &HashMap<PathBuf, String>) -> Result<()> {
    let hash_file = Path::new("scripts/.asset-hashes.json");
    let string_map: HashMap<String, String> = hashes
        .iter()
        .map(|(k, v)| (k.to_string_lossy().into_owned(), v.clone()))
        .collect();
    let content = serde_json::to_string_pretty(&string_map)?;
    fs::write(hash_file, content)?;
    Ok(())
}

fn minify_assets() -> Result<()> {
    // 获取现有文件的哈希
    let current_hashes = get_files_hash()?;

    if current_hashes.is_empty() {
        println!("cargo:warning=No files to minify");
        return Ok(());
    }

    // 加载保存的哈希值
    let saved_hashes = load_saved_hashes()?;

    // 找出需要更新的文件
    let files_to_update: Vec<_> = current_hashes
        .iter()
        .filter(|(path, current_hash)| {
            let ext = path.extension().and_then(|e| e.to_str()).unwrap_or("");
            let min_path = path.with_file_name(format!(
                "{}.min.{}",
                path.file_stem().unwrap().to_string_lossy(),
                ext
            ));

            // 检查压缩后的文件是否存在
            if !min_path.exists() {
                return true;
            }

            // 检查原始文件是否发生变化
            saved_hashes
                .get(*path)
                .map_or(true, |saved_hash| saved_hash != *current_hash)
        })
        .map(|(path, _)| path.file_name().unwrap().to_string_lossy().into_owned())
        .collect();

    if files_to_update.is_empty() {
        println!("cargo:warning=No files need to be updated");
        return Ok(());
    }

    println!("cargo:warning=Minifying {} files...", files_to_update.len());

    // 运行压缩脚本
    let status = Command::new("node")
        .arg("scripts/minify.js")
        .args(&files_to_update)
        .status()?;

    if !status.success() {
        panic!("Asset minification failed");
    }

    // 保存新的哈希值
    save_hashes(&current_hashes)?;

    Ok(())
}

fn main() -> Result<()> {
    // Proto 文件处理
    println!("cargo:rerun-if-changed=src/chat/aiserver/v1/lite.proto");
    let mut config = prost_build::Config::new();
    // config.type_attribute(".", "#[derive(serde::Serialize, serde::Deserialize)]");
    // config.type_attribute(
    //     "aiserver.v1.ThrowErrorCheckRequest",
    //     "#[derive(serde::Serialize, serde::Deserialize)]"
    // );
    config
        .compile_protos(&["src/chat/aiserver/v1/lite.proto"], &["src/chat/aiserver/v1/"])
        .unwrap();

    // 静态资源文件处理
    println!("cargo:rerun-if-changed=scripts/minify.js");
    println!("cargo:rerun-if-changed=scripts/package.json");
    println!("cargo:rerun-if-changed=static");

    // 检查并安装依赖
    check_and_install_deps()?;

    // 运行资源压缩
    minify_assets()?;

    Ok(())
}