use regex::Regex;
use std::error::Error;
use std::fmt;
use std::fs::File as FsFile;
use std::io::Read;
use std::ops::Deref;
use std::path::{Path, PathBuf};

use command_runner::CommandRunner;
use symbols::{Action, OwnedSymbolAction, Symbol, SymbolAction, SymbolRunner};
use resources::Resource;

pub struct WordpressPlugin<'a, C, R> where C: Deref<Target=str> + fmt::Display, R: 'a + CommandRunner {
  base: C,
  name: C,
  command_runner: &'a R
}

impl<'a, C, R> WordpressPlugin<'a, C, R> where C: Deref<Target=str> + fmt::Display, R: CommandRunner {
  pub fn new(base: C, name: C, command_runner: &'a R) -> Self {
    WordpressPlugin {
      base: base,
      name: name,
      command_runner: command_runner
    }
  }

  fn get_path(&self) -> PathBuf {
    Path::new(&*self.base).join("wp-content/plugins").join(&*self.name)
  }
}

impl<'a, C, R> Symbol for WordpressPlugin<'a, C, R> where C: Deref<Target=str> + fmt::Display, R: CommandRunner {
  fn target_reached(&self) -> Result<bool, Box<Error>> {
    if !self.get_path().exists() {
      return Ok(false);
    }
    let path = self.get_path().join(self.name.to_string() + ".php");
    let mut file = try!(FsFile::open(path));
    let mut file_content = String::new();
    try!(file.read_to_string(&mut file_content));
    let mut version = String::new();
    let mut plugin_uri = String::new();
    let regex = try!(Regex::new("(?m)^(Plugin URI|Version): (.+)$"));
    for matches in regex.captures_iter(&file_content) {
      if &matches[1] == "Plugin URI" {
        plugin_uri = matches[2].to_string();
      } else {
        version = matches[2].to_string();
      }
    }
    let upstream = try!(self.command_runner.get_output("curl", &["--form", &format!(r###"plugins={{"plugins":{{"{0}/{0}.php":{{"Version":"{1}", "PluginURI":"{2}"}}}}}}"###, self.name, version, plugin_uri), "https://api.wordpress.org/plugins/update-check/1.1/"]));
    Ok(try!(String::from_utf8(upstream)).contains(r###""plugins":[]"###))
  }

  fn execute(&self) -> Result<(), Box<Error>> {
    let zip = format!("/tmp/{}.zip", self.name);
    try!(self.command_runner.run_successfully("curl", &[&format!("https://downloads.wordpress.org/plugin/{}.zip", self.name), "-o", &zip]));
    try!(self.command_runner.run_successfully("rm", &["-rf", &self.get_path().to_string_lossy()]));
    self.command_runner.run_successfully("unzip", &[&zip, "-d", &Path::new(&*self.base).join("wp-content/plugins").to_string_lossy()])
  }

  fn get_prerequisites(&self) -> Vec<Resource> {
    match self.get_path().parent() {
      Some(p) => vec![ Resource::new("dir", p.to_string_lossy()) ],
      None => vec![]
    }
  }

  fn as_action<'b>(&'b self, runner: &'b SymbolRunner) -> Box<Action + 'b> {
    Box::new(SymbolAction::new(runner, self))
  }

  fn into_action<'b>(self: Box<Self>, runner: &'b SymbolRunner) -> Box<Action + 'b> where Self: 'b {
    Box::new(OwnedSymbolAction::new(runner, *self))
  }
}

impl<'a, C, R> fmt::Display for WordpressPlugin<'a, C, R> where C: Deref<Target=str> + fmt::Display, R: CommandRunner {
  fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error>{
    write!(f, "WordpressPlugin {}", self.name)
  }
}