extern crate actix_web;
extern crate serde;
#[macro_use]
extern crate serde_derive;
extern crate grep;
extern crate time;

use actix_web::{fs, http, server, App, HttpResponse, Query};

use std::error::Error;

use grep::regex::RegexMatcher;
use grep::searcher::sinks::Lossy;
use grep::searcher::{BinaryDetection, SearcherBuilder};
use std::fs::File;

fn main() {
  server::new(|| {
    App::new()
      .route("/service/search", http::Method::GET, search)
      .handler(
        "/",
        fs::StaticFiles::new("../ui/dist/")
          .unwrap()
          .index_file("index.html"),
      )
      .finish()
  }).bind("127.0.0.1:8080")
    .unwrap()
    .run();
}

#[derive(Deserialize)]
struct SearchQuery {
  q: String,
  page: Option<usize>,
  size: Option<usize>,
}

fn search(query: Query<SearchQuery>) -> HttpResponse {
  HttpResponse::Ok()
    .header("Access-Control-Allow-Origin", "*")
    .content_type("text/csv")
    .body(ripgrep(query))
}

fn ripgrep(query: Query<SearchQuery>) -> String {
  let page = query.page.unwrap_or(1);
  let size = query.size.unwrap_or(10);
  let offset = size * (page - 1) + 1;
  let csv_file = File::open("../../torrents.csv");

  println!(
    "query = {} , page = {}, size = {}, offset = {}",
    query.q, page, size, offset
  );

  let results = search_file(csv_file.unwrap(), &query.q).unwrap();

  results[offset - 1..offset + size].join("")
}

fn search_file(file: File, query: &str) -> Result<Vec<String>, Box<Error>> {
  let pattern = query.replace(" ", ".*");

  let matcher = RegexMatcher::new_line_matcher(&pattern)?;
  let mut matches: Vec<String> = vec![];

  let mut searcher = SearcherBuilder::new()
    .binary_detection(BinaryDetection::quit(b'\x00'))
    // .line_number(false)
    .build();

  searcher.search_file(
    &matcher,
    &file,
    Lossy(|_lnum, line| {
      matches.push(line.to_string());
      Ok(true)
    }),
  )?;

  Ok(matches)
}

#[cfg(test)]
mod tests {
  use std::fs::File;
  use time::PreciseTime;

  #[test]
  fn test() {
    let start = PreciseTime::now();
    let results =
      super::search_file(File::open("../../torrents.csv").unwrap(), "sherlock").unwrap();
    assert!(results.len() > 2);
    let end = PreciseTime::now();
    println!("Query took {} seconds.", start.to(end));
  }
}