use crate::common;
use core::fmt;
use std::io::Read;
use std::path::PathBuf;
use std::fs;
use std::env;
use std::fs::{File, Metadata};
use toml;
use serde_derive::Deserialize;

pub struct ConfigFile {
  pub path: String,
  pub file: Metadata,
  pub config: Config
}

impl fmt::Display for ConfigFile {
  fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
    let branches_list = match &self.config.branches {
      None => String::from("All branches"),
      Some(vec) => {
        let mut out = String::from("[");
        for i in 0..vec.len() {
          out = format!("{}{}", out, vec[i]);
          if i < vec.len() - 1 {
            out.push_str(", ");
          }
        }
        out.push(']');
        out
      }
    };

    let mut to_list = String::from("[");
    for i in 0..self.config.to.len() {
      to_list.push_str(&self.config.to[i]);
      if i < self.config.to.len() - 1 {
        to_list.push_str(", ");
      }
    };
    to_list.push(']');

    let work_dir_path = match &self.config.work_dir {
      None => {
        if cfg!(windows) {
          format!("Using default \"{}\\refractr\"", match env::var("TEMP") {
            Ok(val) => val,
            Err(_) => format!("This shouldn't happen!")
          })
        } else {
          format!("Using default: /tmp/refractr")
        }
      },
      Some(path) => format!("{}", path)
    };

    let schedule_interval = match self.config.schedule.interval {
      None => {
        if !self.config.schedule.enabled {
          String::from("")
        } else {
          String::from("This shouldn't happen!\n")
        }
      },
      Some(int) => format!("\n        Scheduled interval in seconds: {}", int.to_string())
    };

    write!(f, "Config file: \"{}\"\n      \
        Is a file: {}\n      \
        Read only: {}\n      \
        Configuration:\n        \
        Git repo to clone: {}\n        \
        Git repos to push clone to: {}\n        \
        Branches of clone to push: {}\n        \
        Working directory: {}\n        \
        SSH key for pushing clone: {}\n        \
        Schedule enabled: {}\
        {}"
      , self.path, self.file.is_file(), self.file.permissions().readonly(), self.config.from
      , to_list, branches_list, work_dir_path, self.config.git.ssh_identity_file, self.config.schedule.enabled
      , schedule_interval)
  }
}

#[derive(PartialEq)]
#[derive(Deserialize)]
pub struct Config {
  pub from: String,
  pub to: Vec<String>,
  pub branches: Option<Vec<String>>,
  pub work_dir: Option<String>,
  pub git: Git,
  pub schedule: Schedule
}

#[derive(PartialEq)]
#[derive(Deserialize)]
pub struct Git {
  pub ssh_identity_file: String,
}

#[derive(PartialEq)]
#[derive(Deserialize)]
pub struct Schedule {
  pub enabled: bool,
  interval: Option<i32>,
}

pub fn read_config(paths: Vec<PathBuf>, refractr: &common::Refractr) -> Vec<ConfigFile> {
  let mut config_files: Vec<ConfigFile> = vec![];
  for path in paths {
    common::verbose(refractr.verbose, 1, format!("Reading config file: \"{}\"", String::from(path.to_string_lossy())));
    let mut data = String::new();
    let mut file = match File::open(path.as_path()) {
      Err(e) => panic!("refractr: unable to open {}: {}", path.as_path().display(), e),
      Ok(file) => file
    };

    if let Err(e) = file.read_to_string(&mut data) {
      panic!("refractr: unable to read {}: {}", path.as_path().display(), e)
    }

    let config_file = ConfigFile {
      path: match fs::canonicalize(&path) {
        Err(_) => panic!("refractr: cannot get absolute path of config file: {}", path.as_path().display()),
        Ok(abs) => abs.to_string_lossy().to_string()
      },
      file: match fs::metadata(&path) {
        Err(_) => panic!("refractr: cannot obtain metadata for config file: {}", path.as_path().display()),
        Ok(metadata) => metadata
      },
      config: verify_config(toml::from_str(&data).unwrap())
    };

    let mut dup = false;
    for i in &config_files {
      if i.path == config_file.path {
        eprintln!("refractr: warning: skipping config file \"{}\" as it was already read", path.as_path().display());
        dup = true;
        break;
      } else if i.config == config_file.config {
        eprintln!("refractr: warning: config files \"{}\" and \"{}\" appear to have the same config", i.path, config_file.path);
      }
    }
    
    if !dup {
      config_files.push(config_file);
    }
  }

  return config_files;
}

fn verify_config(config: Config) -> Config {
  if config.schedule.enabled {
    assert_ne!(config.schedule.interval, None);
  }

  assert_ne!("", match &config.work_dir {
    Some(path) => format!("{}", path),
    None => {
      if cfg!(windows) {
        match env::var("TEMP") {
          Ok(val) => val,
          Err(_) => format!("")
        }
      } else {
        format!("/tmp/refractr")
      }
    },
  });

  return config;
}