mod appstate;
mod cachefile;
mod cli;
mod file;
mod impl_ureq;
mod sharry;

use std::{
    process,
    sync::{
        Arc,
        atomic::{AtomicBool, Ordering},
    },
};

use clap::Parser;
use console::style;
use dialoguer::{Select, theme::ColorfulTheme};
use log::{error, info, trace};

use appstate::AppState;
use cli::Cli;
use sharry::ClientError;

fn prompt_continue() -> bool {
    let prompt = format!(
        "This operation has previously been stopped. {}",
        style("How to proceed?").cyan()
    );

    let choices = [
        format!("Load and {}", style("continue operation").green().bold()),
        format!("Start a {}", style("new operation").cyan().bold()),
        format!("Quit {}", style("ShrUpl").yellow().bold()),
    ];

    let selection = Select::with_theme(&ColorfulTheme::default())
        .with_prompt(prompt)
        .default(0)
        .items(&choices)
        .interact()
        .unwrap_or(2);

    if selection == 2 {
        process::exit(255);
    }

    selection == 0
}

fn handle_error(e: &ClientError) {
    if e.is_fatal() {
        // react to fatal error
        error!("fatal error: {e:?}");
        eprintln!(
            "{} {}",
            style("Error!").red().bold(),
            style(e.to_string()).cyan().italic(),
        );
        process::exit(1);
    }

    // handle recoverable error
    info!("recoverable error: {e:?}");
}

fn main() {
    env_logger::init();

    let check_ctrlc = {
        let stop = Arc::new(AtomicBool::new(false));
        let stop_ctrlc = stop.clone();

        ctrlc::set_handler(move || {
            stop_ctrlc.store(true, Ordering::SeqCst);
            info!("stopping as soon as possible ...");
        })
        .expect("Error setting Ctrl-C handler");

        move || {
            if stop.load(Ordering::SeqCst) {
                process::exit(255);
            }
        }
    };

    let args = Cli::parse();
    info!("args: {args:#?}");

    println!(
        "{} to {}!",
        style("Welcome").magenta().bold(),
        style("ShrUpl").yellow().bold(),
    );

    let mut state = AppState::try_resume(&args)
        .and_then(|state| prompt_continue().then_some(state))
        .unwrap_or_else(|| {
            check_ctrlc();

            match AppState::from_args(&args) {
                Ok(state) => {
                    state.save().unwrap_or_else(|e| {
                        eprintln!(
                            "{} Failed to save {} state: {e}",
                            style("Warning:").red().bold(),
                            style("ShrUpl").yellow().bold(),
                        );
                    });
                    state
                }
                Err(e) => {
                    handle_error(&e);
                    process::exit(1);
                }
            }
        });

    info!("continuing with state: {state:#?}");

    let fns_magenta = state
        .file_names()
        .iter()
        .map(|&n| style(n).magenta().to_string())
        .collect::<Vec<_>>()
        .join(", ");

    println!(
        "{} is uploading: {fns_magenta}",
        style("ShrUpl").yellow().bold(),
    );

    let mut buffer = vec![0; args.chunk_size * 1024 * 1024];

    loop {
        match state.upload_chunk(&mut buffer) {
            Err(e) => {
                // TODO better error handling (this will just retry endlessly)
                // Error 404: Share might have been deleted
                handle_error(&e);

                if let Some(s) = state.rewind() {
                    trace!("State rewound, retrying last chunk");
                    state = s;
                } else {
                    eprintln!("{} Failed to retry chunk!", style("Error:").red().bold());
                    process::exit(1);
                }
            }
            Ok(false) => {
                trace!("chunk uploaded");
            }
            Ok(true) => {
                info!("all uploads done");
                break;
            }
        }

        state.save().unwrap_or_else(|e| {
            eprintln!(
                "{} Failed to save {} state: {e}",
                style("Warning:").red().bold(),
                style("ShrUpl").yellow().bold(),
            );
        });
        check_ctrlc();
    }

    state.clear().unwrap_or_else(|e| {
        eprintln!(
            "{} Failed to remove {} state: {e}",
            style("Warning:").red().bold(),
            style("ShrUpl").yellow().bold(),
        );
    });

    println!(
        "{} finished {}",
        style("ShrUpl").yellow().bold(),
        style("successfully!").green()
    );
}