use crate::config::*;
use crate::utils::{dirs, help};
use anyhow::Result;
use chrono::{Local, TimeZone};
use log::LevelFilter;
use log4rs::append::console::ConsoleAppender;
use log4rs::append::file::FileAppender;
use log4rs::config::{Appender, Logger, Root};
use log4rs::encode::pattern::PatternEncoder;
use std::fs::{self, DirEntry};
use std::str::FromStr;
use tauri::PackageInfo;

/// initialize this instance's log file
fn init_log() -> Result<()> {
    let log_dir = dirs::app_logs_dir()?;
    if !log_dir.exists() {
        let _ = fs::create_dir_all(&log_dir);
    }

    let log_level = Config::verge().data().get_log_level();
    if log_level == LevelFilter::Off {
        return Ok(());
    }

    let local_time = Local::now().format("%Y-%m-%d-%H%M").to_string();
    let log_file = format!("{}.log", local_time);
    let log_file = log_dir.join(log_file);

    let log_pattern = match log_level {
        LevelFilter::Trace => "{d(%Y-%m-%d %H:%M:%S)} {l} [{M}] - {m}{n}",
        _ => "{d(%Y-%m-%d %H:%M:%S)} {l} - {m}{n}",
    };

    let encode = Box::new(PatternEncoder::new(log_pattern));

    let stdout = ConsoleAppender::builder().encoder(encode.clone()).build();
    let tofile = FileAppender::builder().encoder(encode).build(log_file)?;

    let mut logger_builder = Logger::builder();
    let mut root_builder = Root::builder();

    let log_more = log_level == LevelFilter::Trace || log_level == LevelFilter::Debug;

    #[cfg(feature = "verge-dev")]
    {
        logger_builder = logger_builder.appenders(["file", "stdout"]);
        if log_more {
            root_builder = root_builder.appenders(["file", "stdout"]);
        } else {
            root_builder = root_builder.appenders(["stdout"]);
        }
    }
    #[cfg(not(feature = "verge-dev"))]
    {
        logger_builder = logger_builder.appenders(["file"]);
        if log_more {
            root_builder = root_builder.appenders(["file"]);
        }
    }

    let (config, _) = log4rs::config::Config::builder()
        .appender(Appender::builder().build("stdout", Box::new(stdout)))
        .appender(Appender::builder().build("file", Box::new(tofile)))
        .logger(logger_builder.additive(false).build("app", log_level))
        .build_lossy(root_builder.build(log_level));

    log4rs::init_config(config)?;

    Ok(())
}

/// 删除log文件
pub fn delete_log() -> Result<()> {
    let log_dir = dirs::app_logs_dir()?;
    if !log_dir.exists() {
        return Ok(());
    }

    let auto_log_clean = {
        let verge = Config::verge();
        let verge = verge.data();
        verge.auto_log_clean.clone().unwrap_or(0)
    };

    let day = match auto_log_clean {
        1 => 7,
        2 => 30,
        3 => 90,
        _ => return Ok(()),
    };

    log::debug!(target: "app", "try to delete log files, day: {day}");

    // %Y-%m-%d to NaiveDateTime
    let parse_time_str = |s: &str| {
        let sa: Vec<&str> = s.split('-').collect();
        if sa.len() != 4 {
            return Err(anyhow::anyhow!("invalid time str"));
        }

        let year = i32::from_str(sa[0])?;
        let month = u32::from_str(sa[1])?;
        let day = u32::from_str(sa[2])?;
        let time = chrono::NaiveDate::from_ymd_opt(year, month, day)
            .ok_or(anyhow::anyhow!("invalid time str"))?
            .and_hms_opt(0, 0, 0)
            .ok_or(anyhow::anyhow!("invalid time str"))?;
        Ok(time)
    };

    let process_file = |file: DirEntry| -> Result<()> {
        let file_name = file.file_name();
        let file_name = file_name.to_str().unwrap_or_default();

        if file_name.ends_with(".log") {
            let now = Local::now();
            let created_time = parse_time_str(&file_name[0..file_name.len() - 4])?;
            let file_time = Local
                .from_local_datetime(&created_time)
                .single()
                .ok_or(anyhow::anyhow!("invalid local datetime"))?;

            let duration = now.signed_duration_since(file_time);
            if duration.num_days() > day {
                let file_path = file.path();
                let _ = fs::remove_file(file_path);
                log::info!(target: "app", "delete log file: {file_name}");
            }
        }
        Ok(())
    };

    for file in fs::read_dir(&log_dir)? {
        if let Ok(file) = file {
            let _ = process_file(file);
        }
    }
    Ok(())
}

/// Initialize all the config files
/// before tauri setup
pub fn init_config() -> Result<()> {
    #[cfg(target_os = "windows")]
    unsafe {
        let _ = dirs::init_portable_flag();
    }

    let _ = init_log();
    let _ = delete_log();

    crate::log_err!(dirs::app_home_dir().map(|app_dir| {
        if !app_dir.exists() {
            let _ = fs::create_dir_all(&app_dir);
        }
    }));

    crate::log_err!(dirs::app_profiles_dir().map(|profiles_dir| {
        if !profiles_dir.exists() {
            let _ = fs::create_dir_all(&profiles_dir);
        }
    }));

    crate::log_err!(dirs::clash_path().map(|path| {
        if !path.exists() {
            help::save_yaml(&path, &IClashTemp::template().0, Some("# Clash Vergeasu"))?;
        }
        <Result<()>>::Ok(())
    }));

    crate::log_err!(dirs::verge_path().map(|path| {
        if !path.exists() {
            help::save_yaml(&path, &IVerge::template(), Some("# Clash Verge"))?;
        }
        <Result<()>>::Ok(())
    }));

    crate::log_err!(dirs::profiles_path().map(|path| {
        if !path.exists() {
            help::save_yaml(&path, &IProfiles::template(), Some("# Clash Verge"))?;
        }
        <Result<()>>::Ok(())
    }));

    Ok(())
}

/// initialize app resources
/// after tauri setup
pub fn init_resources(package_info: &PackageInfo) -> Result<()> {
    let app_dir = dirs::app_home_dir()?;
    let res_dir = dirs::app_resources_dir(package_info)?;

    if !app_dir.exists() {
        let _ = fs::create_dir_all(&app_dir);
    }
    if !res_dir.exists() {
        let _ = fs::create_dir_all(&res_dir);
    }

    #[cfg(target_os = "windows")]
    let file_list = [
        "Country.mmdb",
        "geoip.dat",
        "geosite.dat",
        "clash-verge-service.exe",
        "install-service.exe",
        "uninstall-service.exe",
    ];
    #[cfg(not(target_os = "windows"))]
    let file_list = ["Country.mmdb", "geoip.dat", "geosite.dat"];

    // copy the resource file
    // if the source file is newer than the destination file, copy it over
    for file in file_list.iter() {
        let src_path = res_dir.join(file);
        let dest_path = app_dir.join(file);

        let handle_copy = || {
            match fs::copy(&src_path, &dest_path) {
                Ok(_) => log::debug!(target: "app", "resources copied '{file}'"),
                Err(err) => {
                    log::error!(target: "app", "failed to copy resources '{file}', {err}")
                }
            };
        };

        if src_path.exists() && !dest_path.exists() {
            handle_copy();
            continue;
        }

        let src_modified = fs::metadata(&src_path).and_then(|m| m.modified());
        let dest_modified = fs::metadata(&dest_path).and_then(|m| m.modified());

        match (src_modified, dest_modified) {
            (Ok(src_modified), Ok(dest_modified)) => {
                if src_modified > dest_modified {
                    handle_copy();
                } else {
                    log::debug!(target: "app", "skipping resource copy '{file}'");
                }
            }
            _ => {
                log::debug!(target: "app", "failed to get modified '{file}'");
                handle_copy();
            }
        };
    }

    Ok(())
}