extern crate clap;

use self::clap::{App, Arg};
use clap::crate_version;
use regex::Regex;
use std::process::Command;

trait Executor {
  fn execute(&mut self, args: Vec<String>) -> String;
  fn last_executed(&self) -> Option<Vec<String>>;
}

struct RealShell {
  executed: Option<Vec<String>>,
}

impl RealShell {
  fn new() -> RealShell {
    RealShell { executed: None }
  }
}

impl Executor for RealShell {
  fn execute(&mut self, args: Vec<String>) -> String {
    let execution = Command::new(args[0].as_str())
      .args(&args[1..])
      .output()
      .expect("Couldn't run it");

    self.executed = Some(args);

    String::from_utf8_lossy(&execution.stdout).into()
  }

  fn last_executed(&self) -> Option<Vec<String>> {
    self.executed.clone()
  }
}

const TMP_FILE: &str = "/tmp/thumbs-last";
const TMUX_SIGNAL: &str = "thumbs-finished";

pub struct Swapper<'a> {
  executor: Box<&'a mut dyn Executor>,
  command: String,
  upcase_command: String,
  active_pane_id: Option<String>,
  thumbs_pane_id: Option<String>,
  content: Option<String>,
}

impl<'a> Swapper<'a> {
  fn new(executor: Box<&'a mut dyn Executor>, command: String, upcase_command: String) -> Swapper {
    Swapper {
      executor: executor,
      command: command,
      upcase_command: upcase_command,
      active_pane_id: None,
      thumbs_pane_id: None,
      content: None,
    }
  }

  pub fn capture_active_pane(&mut self) {
    let active_command = vec![
      "tmux",
      "list-panes",
      "-F",
      "#{pane_id}:#{?pane_active,active,nope}",
    ];
    let output = self
      .executor
      .execute(active_command.iter().map(|arg| arg.to_string()).collect());
    let lines: Vec<&str> = output.split("\n").collect();
    let chunks: Vec<Vec<&str>> = lines
      .into_iter()
      .map(|line| line.split(":").collect())
      .collect();

    let chunk = chunks
      .iter()
      .find(|&chunks| *chunks.iter().nth(1).unwrap() == "active")
      .expect("Unable to find active pane");

    let pane_id = chunk.iter().nth(0).unwrap().to_string();

    self.active_pane_id = Some(pane_id);
  }

  pub fn execute_thumbs(&mut self) {
    let options_command = vec!["tmux", "show", "-g"];
    let params: Vec<String> = options_command.iter().map(|arg| arg.to_string()).collect();
    let options = self.executor.execute(params);
    let lines: Vec<&str> = options.split("\n").collect();

    let pattern = Regex::new(r#"@thumbs-([\w\-0-9]+) "(.*)""#).unwrap();

    let args = lines
      .iter()
      .flat_map(|line| {
        if let Some(captures) = pattern.captures(line) {
          let name = captures.get(1).unwrap().as_str();
          let value = captures.get(2).unwrap().as_str();

          let boolean_params = vec!["reverse", "unique", "contrast"];

          if boolean_params.iter().any(|&x| x == name) {
            return vec![format!("--{}", name).to_string()];
          }

          let string_params = vec![
            "position",
            "fg-color",
            "bg-color",
            "hint-bg-color",
            "hint-fg-color",
            "select-fg-color",
            "select-bg-color",
          ];

          if string_params.iter().any(|&x| x == name) {
            return vec![
              format!("--{}", name).to_string(),
              format!("'{}'", value).to_string(),
            ];
          }

          if name.starts_with("regexp") {
            return vec!["--regexp".to_string(), format!("'{}'", value).to_string()];
          }

          vec![]
        } else {
          vec![]
        }
      })
      .collect::<Vec<String>>();

    let pane_command = format!("tmux capture-pane -t \"{}\" -p | ./target/release/thumbs -f '%U:%H' {} | tee {}; tmux wait-for -S {}", self.active_pane_id.clone().unwrap(), args.join(" "), TMP_FILE, TMUX_SIGNAL);
    let thumbs_command = vec![
      "tmux",
      "new-window",
      "-P",
      "-n",
      "[thumbs]",
      pane_command.as_str(),
    ];
    let params: Vec<String> = thumbs_command.iter().map(|arg| arg.to_string()).collect();

    self.thumbs_pane_id = Some(self.executor.execute(params));
  }

  pub fn swap_panes(&mut self) {
    let active_pane_id = self.active_pane_id.as_mut().unwrap().clone();
    let thumbs_pane_id = self.thumbs_pane_id.as_mut().unwrap().clone();

    let swap_command = vec![
      "tmux",
      "swap-pane",
      "-d",
      "-s",
      active_pane_id.as_str(),
      "-t",
      thumbs_pane_id.as_str(),
    ];
    let params = swap_command.iter().map(|arg| arg.to_string()).collect();

    self.executor.execute(params);
  }

  pub fn wait_thumbs(&mut self) {
    let wait_command = vec!["tmux", "wait-for", TMUX_SIGNAL];
    let params = wait_command.iter().map(|arg| arg.to_string()).collect();

    self.executor.execute(params);
  }

  pub fn retrieve_content(&mut self) {
    let retrieve_command = vec!["cat", TMP_FILE];
    let params = retrieve_command.iter().map(|arg| arg.to_string()).collect();

    self.content = Some(self.executor.execute(params));
  }

  pub fn destroy_content(&mut self) {
    let retrieve_command = vec!["rm", "/tmp/thumbs-last"];
    let params = retrieve_command.iter().map(|arg| arg.to_string()).collect();

    self.executor.execute(params);
  }

  pub fn execute_command(&mut self) {
    let content = self.content.clone().unwrap();
    let mut splitter = content.splitn(2, ':');
    let upcase = splitter.next().unwrap().trim_end();
    let text = splitter.next().unwrap().trim_end();

    let execute_command = if upcase == "true" {
      self.upcase_command.clone()
    } else {
      self.command.clone()
    };

    let final_command = str::replace(execute_command.as_str(), "{}", text);
    let retrieve_command = vec!["bash", "-c", final_command.as_str()];
    let params = retrieve_command.iter().map(|arg| arg.to_string()).collect();

    self.executor.execute(params);
  }
}

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

  struct TestShell {
    outputs: Vec<String>,
    executed: Option<Vec<String>>,
  }

  impl TestShell {
    fn new(outputs: Vec<String>) -> TestShell {
      TestShell {
        executed: None,
        outputs: outputs,
      }
    }
  }

  impl Executor for TestShell {
    fn execute(&mut self, args: Vec<String>) -> String {
      self.executed = Some(args);
      self.outputs.pop().unwrap()
    }

    fn last_executed(&self) -> Option<Vec<String>> {
      self.executed.clone()
    }
  }

  #[test]
  fn retrieve_active_pane() {
    let last_command_outputs = vec!["%97:active\n%106:nope\n%107:nope\n".to_string()];
    let mut executor = TestShell::new(last_command_outputs);
    let mut swapper = Swapper::new(Box::new(&mut executor), "".to_string(), "".to_string());

    swapper.capture_active_pane();

    assert_eq!(swapper.active_pane_id.unwrap(), "%97");
  }

  #[test]
  fn swap_panes() {
    let last_command_outputs = vec![
      "".to_string(),
      "%100".to_string(),
      "".to_string(),
      "%106:nope\n%98:active\n%107:nope\n".to_string(),
    ];
    let mut executor = TestShell::new(last_command_outputs);
    let mut swapper = Swapper::new(Box::new(&mut executor), "".to_string(), "".to_string());

    swapper.capture_active_pane();
    swapper.execute_thumbs();
    swapper.swap_panes();

    let expectation = vec!["tmux", "swap-pane", "-d", "-s", "%98", "-t", "%100"];

    assert_eq!(executor.last_executed().unwrap(), expectation);
  }
}
fn app_args<'a>() -> clap::ArgMatches<'a> {
  return App::new("tmux-thumbs")
    .version(crate_version!())
    .about("A lightning fast version of tmux-fingers, copy/pasting tmux like vimium/vimperator")
    .arg(
      Arg::with_name("command")
        .help("Pick command")
        .long("command")
        .default_value("tmux set-buffer {}"),
    )
    .arg(
      Arg::with_name("upcase_command")
        .help("Upcase command")
        .long("upcase-command")
        .default_value("tmux set-buffer {} && tmux paste-buffer"),
    )
    .get_matches();
}

fn main() {
  let args = app_args();
  let command = args.value_of("command").unwrap();
  let upcase_command = args.value_of("upcase_command").unwrap();

  let mut executor = RealShell::new();
  let mut swapper = Swapper::new(
    Box::new(&mut executor),
    command.to_string(),
    upcase_command.to_string(),
  );

  swapper.capture_active_pane();
  swapper.execute_thumbs();
  swapper.swap_panes();
  swapper.wait_thumbs();
  swapper.retrieve_content();
  swapper.destroy_content();
  swapper.execute_command();
}