use crate::config::paths;
use colored::Colorize;
use fancy_regex::Regex;
use std::fs::{self, File};
use std::io::{BufRead, BufReader, Seek, SeekFrom};
use std::process;
use std::time::Duration;
use tokio::time::sleep;
pub async fn tail_logs(no_color: bool) {
let re = Regex::new(r"^(?P<timestamp>\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}\.\d{3})\s+<(?P<opid>[^\s>]+)>\s+\[(?P<level>[A-Z]+)\]\s+(?P<logger>[^:]+):(?P<line>\d+)\s+-\s+(?P<message>.*)$").unwrap();
let file_path = paths::log_file();
let file = File::open(&file_path).expect("Cannot open file");
let mut reader = BufReader::new(file);
if let Err(e) = reader.seek(SeekFrom::End(0)) {
eprintln!("Unable to tail log file: {e:?}");
process::exit(1);
};
let mut line_buf = String::new();
loop {
match reader.read_line(&mut line_buf) {
Ok(0) => {
if file_was_rotated(&file_path, &mut reader) {
let file = File::open(&file_path).expect("Cannot open file");
reader = BufReader::new(file);
}
sleep(Duration::from_millis(100)).await;
}
Ok(_) => {
let line = line_buf.trim_end();
if no_color {
println!("{line}");
} else {
let colored_line = colorize_log_line(line, &re);
println!("{colored_line}");
}
line_buf.clear();
}
Err(_) => {
line_buf.clear();
sleep(Duration::from_millis(100)).await;
}
}
}
}
fn file_was_rotated(path: &std::path::Path, reader: &mut BufReader<File>) -> bool {
let current_pos = reader.stream_position().unwrap_or(0);
match fs::metadata(path) {
Ok(metadata) => metadata.len() < current_pos,
Err(_) => true,
}
}
fn colorize_log_line(line: &str, re: &Regex) -> String {
if let Some(caps) = re.captures(line).expect("Failed to capture log line") {
let level = &caps["level"];
let message = &caps["message"];
let colored_message = match level {
"ERROR" => message.red(),
"WARN" => message.yellow(),
"INFO" => message.green(),
"DEBUG" => message.blue(),
_ => message.normal(),
};
let timestamp = &caps["timestamp"];
let opid = &caps["opid"];
let logger = &caps["logger"];
let line_number = &caps["line"];
format!(
"{} <{}> [{}] {}:{} - {}",
timestamp.white(),
opid.cyan(),
level.bold(),
logger.magenta(),
line_number.bold(),
colored_message
)
} else {
line.to_string()
}
}