[package]
name = "qsu"
version = "0.5.0"
edition = "2021"
license = "0BSD"
# https://crates.io/category_slugs
categories = [ "os" ]
keywords = [ "service", "systemd", "winsvc" ]
repository = "https://repos.qrnch.tech/pub/qsu"
description = "Service subsystem wrapper."

use std::{
  env, fmt, fs,
  io::Write,
  path::{Path, PathBuf},
  str::FromStr
};

use time::macros::format_description;

use tracing_subscriber::{fmt::time::UtcTime, EnvFilter};

#[cfg(feature = "clap")]
use clap::ValueEnum;

use crate::err::Error;

}

/// Logging and tracing initialization.
pub struct LumberJack {
  init: bool,
  log_out: LogOut,
  log_level: LogLevel,
  trace_filter: Option<String>,
  //log_file: Option<PathBuf>,
  trace_file: Option<PathBuf>
}

impl Default for LumberJack {
  /// Create a default log/trace initialization.
  ///
  /// This will set the `log` log level to the value of the `LOG_LEVEL`
  /// environment variable, or default to `warm` (if either not set or
  /// invalid).
  ///
  /// The `tracing` trace level will use the environment variable
  /// `TRACE_FILTER` in a similar manner, but defaults to `none`.
  ///
  /// If the environment variable `TRACE_FILE` is set the value will be the
  /// used as the file name to write the trace logs to.
  fn default() -> Self {
    let log_level = if let Ok(level) = std::env::var("LOG_LEVEL") {
      if let Ok(level) = level.parse::<LogLevel>() {
        level
      } else {
        LogLevel::Warn
      }
    } else {
      LogLevel::Warn
    };

    let trace_file = if let Ok(v) = std::env::var("TRACE_FILE") {
      Some(PathBuf::from(v))
    } else {
      None
    };

    let trace_filter = if let Ok(var) = env::var("TRACE_FILTER") {
      Some(var.to_string())

    } else {
      None



    };

    Self {
      init: true,
      log_out: Default::default(),
      log_level,
      trace_filter,
      //log_file: None,
      trace_file
    }
  }
}

impl LumberJack {

  pub fn from_winsvc(svcname: &str) -> Result<Self, Error> {
    let params = crate::rt::winsvc::get_service_param(svcname)?;
    let loglevel = params
      .get_value::<String, &str>("LogLevel")
      .unwrap_or(String::from("warn"))
      .parse::<LogLevel>()
      .unwrap_or(LogLevel::Warn);
    let tracefilter = params.get_value::<String, &str>("TraceFilter");
    let tracefile = params.get_value::<String, &str>("TraceFile");

    let mut this = Self::new().log_level(loglevel);
    this.log_out = LogOut::WinEvtLog {
      svcname: svcname.to_string()
    };
    let this =
      if let (Ok(tracefilter), Ok(tracefile)) = (tracefilter, tracefile) {


        this.trace_filter(tracefilter).trace_file(tracefile)
      } else {
        this
      };

    Ok(this)
  }

  /// Set the `log` logging level.
  pub fn log_level(mut self, level: LogLevel) -> Self {
    self.log_level = level;
    self
  }

  /// Set the `tracing` log level.
  pub fn trace_filter(mut self, filter: impl ToString) -> Self {
    self.trace_filter = Some(filter.to_string());
    self
  }

  /// Set a file to which `tracing` log entries are written (rather than to
  /// write to console).
  pub fn trace_file<P>(mut self, fname: P) -> Self
  where

        LogOut::WinEvtLog { svcname } => {
          eventlog::init(&svcname, log::Level::Trace)?;
          log::set_max_level(self.log_level.into());
        }
      }

      if let Some(fname) = self.trace_file {
        init_file_tracing(fname, self.trace_filter.as_deref());
      } else {
        init_console_tracing(self.trace_filter.as_deref());
      }

      Ok(())
    } else {
      Ok(())
    }
  }

    .filter(None, lf)
    .init();

  Ok(())
}


pub fn init_console_tracing(filter: Option<&str>) {

  /*
  let subscriber = FmtSubscriber::builder().with_max_level(lvl).finish();
  tracing::subscriber::set_global_default(subscriber)
    .expect("setting default subscriber failed");
  */


  // When running on console, then disable tracing by default
  let filter = if let Some(spec) = filter {
    EnvFilter::new(spec)
  } else {
    EnvFilter::new("none")
  };

  tracing_subscriber::fmt()
    .with_env_filter(filter)
    //.with_timer(timer)
    .init();
}


/// Optionally set up tracing to a file.
///
/// This function will attempt to set up tracing to a file.  There are three
/// conditions that must be true in order for tracing to a file to be enabled:
/// - A filename must be specified (either via the `fname` argument or the
///   `TRACE_FILE` environment variable).
/// - A trace filter must be specified (either via the `filter` argument or the
///  `TRACE_FILTER` environment variable).
/// - The file name must be openable for writing.
///
/// Because tracing is an optional feature and intended for development only,
/// this function will enable tracing if possible, and silently ignore and
/// errors.
pub fn init_file_tracing<P>(fname: P, filter: Option<&str>)
where
  P: AsRef<Path>
{



  //
  // If both a trace file name and a trace level
  //
  let timer = UtcTime::new(format_description!(
    "[year]-[month]-[day] [hour]:[minute]:[second]"
  ));

  let f = if let Ok(f) =
    fs::OpenOptions::new().create(true).append(true).open(fname)
  {
    f
  } else {
    return;
  };

  //
  // If TRACING_FILE is set, then default to filter out at warn level.
  // Disable all tracing if TRACE_FILTER is not set
  //
  let filter = if let Some(spec) = filter {
    EnvFilter::new(spec)
  } else {
    EnvFilter::new("warn")
    /*
    EnvFilter::builder()
      .with_default_directive(LevelFilter::OFF.into())
      .parse("")
      .unwrap()
      */
  };

  tracing_subscriber::fmt()
    .with_env_filter(filter)
    .with_writer(f)
    .with_ansi(false)

    .with_timer(timer)
    .init();

  //tracing_subscriber::registry().with(filter).init();
}

// vim: set ft=rust et sw=2 ts=2 sts=2 cinoptions=2 tw=79 :

# Change log

⚠️  indicates a breaking change.

## [Unreleased]

[Details](/vdiff?from=qsu-0.5.0&to=trunk)

### Added

### Changed

### Removed

---

## [0.5.0] - 2024-05-20

[Details](/vdiff?from=qsu-0.4.1&to=qsu-0.5.0)

### Added

- `TRACE_FILTER` environment variable used to configure tracing to output.
- `TraceFilter` registry key on Windows used to configure tracing output.

### Changed

- ⚠️ Instead of specifying a "trace level" (similar to "log level"), specify a
  "trace filter", allowing fine-grained control of modules to include in
  traces.

### Removed

- `TRACE_LEVEL` environment variable no longer used.
- `TraceLevel` registry key on Windows no longer used.

---

## [0.4.1] - 2024-05-19

[Details](/vdiff?from=qsu-0.4.0&to=qsu-0.4.1)

### Added