use anyhow::Context;
use chrono::prelude::*;
use chrono_humanize::{Accuracy, HumanTime, Tense};
use futures::stream::StreamExt;
use tokio::io::AsyncBufReadExt;
use tokio::io::BufReader;
use tokio_stream::wrappers::LinesStream;
use tracing::{debug, info};

use args::ARGS;

mod args;
mod compression;
mod connector;
mod pbar;
mod project_config;

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    pbar::setup_logging();

    let mut con = {
        let redis_url = project_config::get_redis_url()
            .await
            .context("getting project redis url")?;
        info!("Connecting to project redis...");
        let proj_client = redis::Client::open(redis_url).context("project redis client connect")?;
        let c = proj_client
            .get_async_connection()
            .await
            .context("project redis get_async_connection")?;
        info!("Connected!");
        c
    };

    let (reader, total_bytes) = connector::open(true).await.context("opening input")?;

    //Turn bytes into lines.
    let reader = BufReader::new(reader);
    let reader = reader.lines();
    let reader = LinesStream::new(reader);

    //Gather the lines into chunks of given size.
    let reader = reader.chunks(ARGS.chunk_size);

    //Gather the chunks into the pipelines.
    let mut reader = reader.chunks(ARGS.pipeline_size);

    //Keep track of some statistics.
    let mut counter = 0usize;
    let mut last_stamp: DateTime<Utc> = Utc::now();
    let start_stamp = last_stamp.clone();

    //Initialize the progress bar.
    if !ARGS.no_progressbar {
        if let Some(total_size) = total_bytes {
            pbar::create_progress_bar(total_size);
        }
    }

    let redis_key = format!("{}:{}", ARGS.project, ARGS.queue);
    info!(
        "Writing into key {:?} using {} items per SADD and {} SADDS per pipeline...",
        redis_key, ARGS.chunk_size, ARGS.pipeline_size
    );

    //Main processing loop
    while let Some(chunks) = reader.next().await {
        let mut pipeline = &mut redis::pipe();
        let mut pipeline_counter = 0usize;

        //Create the pipeline commands.
        for chunk in chunks.into_iter() {
            let items: Vec<String> = chunk
                .into_iter()
                .collect::<std::io::Result<Vec<String>>>()
                .context("reading items")?;

            debug!("Queueing chunk of {} items into pipeline...", items.len());
            pipeline_counter += items.len();
            pipeline = pipeline.sadd(&redis_key, items).ignore();
        }

        //Submit pipeline
        debug!("Submitting pipeline with {} items...", pipeline_counter);
        pipeline
            .query_async(&mut con)
            .await
            .context("performing pipeline query")?;
        counter += pipeline_counter;

        //Compute statistics.
        let curr_stamp: DateTime<Utc> = Utc::now();
        let elapsed = curr_stamp.signed_duration_since(last_stamp);
        let elapsed_millis = elapsed.num_milliseconds();
        let elapsed_secs = (elapsed_millis as f64) / 1000.0f64;
        last_stamp = curr_stamp;
        let ips = (pipeline_counter as f64) / elapsed_secs;

        //Update the progressbar if it exists or print a message instead.
        {
            let pb = pbar::PROGRESS_BAR.lock().unwrap();
            if let Some(pb) = pb.as_ref() {
                pb.set_message(format!("{} items ({:.02} items/s)", counter, ips));
            } else {
                let ht = HumanTime::from(curr_stamp.signed_duration_since(start_stamp));
                info!("Items queued! Inserted {} items so far in {}. Inserted {} items this round in {:.03} seconds. ({:.03} items/s)",
                    counter,
                    ht.to_text_en(Accuracy::Rough, Tense::Present),
                    pipeline_counter,
                    elapsed_secs,
                    ips
                );
            }
        }
    }

    //We're done, close off the progress bar.
    pbar::finish_progress_bar();

    //Print some last information.
    {
        let end_stamp: DateTime<Utc> = Utc::now();
        let ht = HumanTime::from(end_stamp.signed_duration_since(start_stamp));
        info!(
            "Finished queueing in {}.",
            ht.to_text_en(Accuracy::Precise, Tense::Present)
        );
    }
    Ok(())
}