#!/usr/bin/env runrs

//! ```cargo
//! [dependencies]
//! serde = { version = "1.0", features = ["derive"] }
//! serde_json = "1.0"
//! sha256 = "1.5"
//! rust_util = { version = "0.6" }
//! ```

use rust_util::{debugging, failure_and_exit, opt_result, opt_value_result, success, XResult};
use serde::Serialize;
use std::collections::BTreeMap;
use std::fs;
use std::path::PathBuf;

const SCRIPT_META_FILE: &str = "script-meta.json";

#[derive(Serialize)]
struct ScriptMeta {
    script_name: String,
    script_length: u64,
    script_sha256: String,
}

fn main() -> XResult<()> {
    if fs::metadata(SCRIPT_META_FILE).is_err() {
        failure_and_exit!("Script meta file {} not found.", SCRIPT_META_FILE);
    }

    let mut script_meta_map = BTreeMap::new();

    let current_read_dir = opt_result!(fs::read_dir("."), "Read dir '.' failed: {}");
    for dir in current_read_dir {
        let dir_entry = opt_result!(dir, "Get dir failed: {}");
        let dir_file_type = opt_result!(dir_entry.file_type(), "Get dir type failed: {}");
        let file_name_os_string = dir_entry.file_name();
        let script_dir = opt_value_result!(file_name_os_string.to_str(), "Cannot get file name.");
        if !dir_file_type.is_dir() {
            debugging!("Skip none dir: {}", script_dir);
            continue;
        }
        if /*"update-meta-rs" == script_dir ||*/ script_dir.starts_with(".") {
            debugging!("Skip update meta rs: {}", script_dir);
            continue;
        }
        let abs_dir_entry = std::path::absolute(&dir_entry.path())?;
        let main_rs = abs_dir_entry
            .join("main.dart");

        script_meta_map.insert(
            script_dir.to_string(),
            read_script_meta(script_dir, &main_rs)?,
        );
    }

    let script_meta_json = serde_json::to_string_pretty(&script_meta_map)?;

    fs::write(SCRIPT_META_FILE, script_meta_json.as_bytes())?;

    success!("Update file: {} succeed.", SCRIPT_META_FILE);

    Ok(())
}

fn read_script_meta(file_name: &str, main_rs: &PathBuf) -> XResult<ScriptMeta> {
    let main_rs_meta = opt_result!(main_rs.metadata(), "Read file: {:?} meta failed: {}", main_rs);
    let main_rs_content = fs::read(main_rs)?;
    let script_sha256 = sha256::digest(&main_rs_content);
    Ok(ScriptMeta {
        script_name: file_name.to_string(),
        script_length: main_rs_meta.len(),
        script_sha256,
    })
}