use std::str::FromStr;
use std::{env, error::Error, path::PathBuf, thread};

use native_dialog::{MessageDialog, MessageType};
use parking_lot::Once;
use tracing::error;

static INIT: Once = Once::new();

pub fn set_panic_hook() {
    INIT.call_once(|| {
        let default_hook = std::panic::take_hook();
        std::panic::set_hook(Box::new(move |info| {
            if let Err(e) = process_panic(info) {
                eprintln!("Error in panic hook: {}", e);
                default_hook(info);
            }
            std::process::exit(1);
        }));
    });
}

fn process_panic(info: &std::panic::PanicHookInfo<'_>) -> Result<(), Box<dyn Error>> {
    use std::io::Write;

    use colored::Colorize;

    let log_dir = PathBuf::from_str("./").expect("wtf, The current directory no longer exists?");
    if !log_dir.exists() {
        std::fs::create_dir_all(&log_dir)?;
    }
    let log_path = log_dir.join("panic.log");

    let mut file = std::fs::File::create(&log_path)?;
    let payload = info.payload();
    let payload_str = if let Some(s) = payload.downcast_ref::<&str>() {
        *s
    } else if let Some(s) = payload.downcast_ref::<String>() {
        s
    } else {
        "<non-string panic payload>"
    };

    writeln!(file, "Panic Occurred: {}", payload_str)?;

    if let Some(location) = info.location() {
        writeln!(file, "Panic Location: {}", location)?;
    }

    writeln!(file, "{}", capture_backtrace().sanitize_path())?;

    // Add more contextual information
    writeln!(file, "\n--- Additional Information ---")?;

    // Rust Version
    if let Ok(rust_version) = rust_version() {
        writeln!(file, "Rust Version: {}", rust_version)?;
    }

    // Command-line Arguments
    writeln!(file, "Command-line Arguments:")?;
    for arg in env::args() {
        writeln!(file, "  {}", arg)?;
    }

    // Environment Variables (consider filtering sensitive ones)
    writeln!(file, "\nEnvironment Variables (selected):")?;
    let interesting_env_vars = ["PATH", "RUST_VERSION", "CARGO_TARGET_DIR", "HOME", "USER"];
    for (key, value) in env::vars() {
        if interesting_env_vars.contains(&key.as_str()) {
            writeln!(file, "  {}: {}", key, value)?;
        }
    }

    // Current Working Directory
    if let Ok(cwd) = env::current_dir() {
        writeln!(file, "\nCurrent Working Directory: {}", cwd.display())?;
    }

    // Thread Information
    if let Some(thread) = thread::current().name() {
        writeln!(file, "\nThread Name: {}", thread)?;
    } else {
        writeln!(file, "\nThread ID: {:?}", thread::current().id())?;
    }

    let panic_msg = format!(
        r#"Zenyx had a problem and crashed. To help us diagnose the problem you can send us a crash report.

We have generated a detailed report file at '{}'. Submit an issue or email with the subject of 'Zenyx Crash Report' and include the report as an attachment.

To submit the crash report:
https://codeberg.org/Caznix/Zenyx/issues
We take privacy seriously, and do not perform any automated error collection. In order to improve the software, we rely on people to submit reports.

Thank you kindly!"#,
        log_path.display()
    );

    let final_msg = format!(
        r#"{}

For future reference, the error summary is as follows:
{}

More details can be found in the crash report file."#,
        panic_msg, payload_str
    );

    println!("{}", final_msg.red().bold());

    if let Err(e) = MessageDialog::new()
        .set_type(MessageType::Error)
        .set_title("A fatal error in Zenyx has occurred")
        .set_text(&final_msg)
        .show_confirm()
    {
        error!("Failed to show message dialog: {e}")
    }

    Ok(())
}

fn rust_version() -> Result<String, Box<dyn Error>> {
    let version = env!("CARGO_PKG_RUST_VERSION");
    Ok(version.to_string())
}

fn capture_backtrace() -> String {
    let mut backtrace = String::new();
    let sysinfo = crate::metadata::SystemMetadata::current();
    backtrace.push_str(&format!(
        "--- System Information ---\n{}\n",
        sysinfo.verbose_summary()
    ));

    let trace = std::backtrace::Backtrace::force_capture();
    let message = format!("\n--- Backtrace ---\n\n");
    backtrace.push_str(&message);
    backtrace.push_str(&format!("{trace:#}"));

    backtrace
}

trait Sanitize {
    fn sanitize_path(&self) -> String;
}

impl Sanitize for str {
    fn sanitize_path(&self) -> String {
        let prefixes = ["/home/", "/Users/", "\\Users\\", "/opt/home/"];
        let mut result = String::from(self);

        for prefix in prefixes {
            if let Some(start_index) = result.find(prefix) {
                let start_of_user = start_index + prefix.len();
                let mut end_of_user = result[start_of_user..]
                    .find(|c| c == '/' || c == '\\')
                    .map(|i| start_of_user + i)
                    .unwrap_or(result.len());
                if end_of_user == start_of_user && start_of_user < result.len() {
                    end_of_user = result.len();
                }
                result.replace_range(start_of_user..end_of_user, "<USER>");
                break;
            }
        }
        result
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_sanitize_home() {
        assert_eq!(
            "/home/<USER>/documents",
            "/home/john.doe/documents".sanitize_path()
        );
        assert_eq!("/home/<USER>", "/home/jane".sanitize_path());
        assert_eq!("/opt/home/<USER>", "/opt/home/user".sanitize_path());
    }

    #[test]
    fn test_sanitize_users_unix() {
        assert_eq!(
            "/Users/<USER>/desktop",
            "/Users/alice/desktop".sanitize_path()
        );
        assert_eq!("/Users/<USER>/", "/Users/bob/".sanitize_path());
        assert_eq!("/user/Users/<USER>", "/user/Users/name".sanitize_path());
    }

    #[test]
    fn test_sanitize_users_windows() {
        assert_eq!(
            "\\Users\\<USER>\\documents",
            "\\Users\\charlie\\documents".sanitize_path()
        );
        assert_eq!("\\Users\\<USER>", "\\Users\\david".sanitize_path());
        assert_eq!(
            "C:\\Other\\Users\\<USER>",
            "C:\\Other\\Users\\folder".sanitize_path()
        );
    }

    #[test]
    fn test_no_match() {
        assert_eq!("/opt/data/file.txt", "/opt/data/file.txt".sanitize_path());
    }

    #[test]
    fn test_mixed_separators() {
        assert_eq!(
            "/home/<USER>\\documents",
            "/home/eve\\documents".sanitize_path()
        );
        assert_eq!(
            "\\Users\\<USER>/desktop",
            "\\Users\\frank/desktop".sanitize_path()
        );
    }
}