use serde::Serialize;
use serde::Deserialize;
use std::fs;
use std::env;

#[derive(Serialize, Deserialize, Debug)]
pub struct Config {
   pub streams: Streams,
}

#[derive(Serialize, Deserialize, Debug)]
pub struct Streams {
   pub input: Stream,
   pub output: Stream,
}

#[derive(Serialize, Deserialize, Debug)]
pub struct Stream {
   pub engine: Engine,
   pub format: Option<String>,
   pub debug: bool,
}

#[derive(Serialize, Deserialize, Debug)]
pub struct Engine {
   pub name: String,
   pub kafka: Option<Kafka>,
   pub device: Option<Device>,
   pub udp: Option<UDP>,
   pub gui: Option<GUI>,
}

#[derive(Serialize, Deserialize, Debug)]
pub struct Device {
}

#[derive(Serialize, Deserialize, Debug)]
pub struct GUI {
   pub buttons: Buttons,
   pub press: PreSufFix,
   pub release: PreSufFix,
   pub format: Option<String>,
   pub user: String,
   pub feedback: GUIFeedback,
}

#[derive(Serialize, Deserialize, Debug, Clone)]
pub struct GUIFeedback {
   pub url: Option<String>,
}

#[derive(Serialize, Deserialize, Debug)]
pub struct PreSufFix {
   pub prefix: String,
   pub suffix: String,
}

#[derive(Serialize, Deserialize, Debug)]
pub struct Buttons {
   pub up: String,
   pub down: String,
   pub left: String,
   pub right: String,
   pub a: String,
   pub b: String,
   pub x: String,
   pub y: String,
   pub l: String,
   pub r: String,
}

#[derive(Serialize, Deserialize, Debug)]
pub struct Kafka {
   pub addr: String,
   pub topic: String,
   pub consumer_group: String,
   pub crt: String,
}

#[derive(Serialize, Deserialize, Debug)]
pub struct UDP {
   pub host: Option<String>,
   pub port: i32,
}

pub fn build_config() -> Result<Config, String> {
   match env::var("CONFIG_PATH") {
      Ok(p) => return build_config_yaml(p),
      Err(_) => match build_config_yaml(String::from("./rusty-pipe.yaml")) {
         Ok(v) => return Ok(v),
         Err(_) => return Ok(build_config_std()),
      },
   };
}

fn build_config_yaml(path: String) -> Result<Config, String> {
   match fs::read_to_string(&path) {
      Ok(buffer) => match serde_yaml::from_str(&buffer) {
         Ok(result) => Ok(result),
         Err(err) => Err(err.to_string()),
      },
      Err(err) => Err(err.to_string()),
   }
}

fn build_config_std() -> Config {
   return Config {
      streams: Streams{
         input: Stream {
            debug: env::var("DEBUG").unwrap_or(String::from("false")) == "true",
            format: match env::var("INPUT_FORMAT") {
               Ok(x) => Some(x),
               Err(_) => None,
            },
            engine: Engine{
               name: env::var("INPUT_NAME").unwrap_or(String::from("stdin")),
               kafka: None,
               gui: Some(GUI{
                  buttons: Buttons{
                     up: env::var("INPUT_GUI_BUTTON_UP").unwrap_or(String::from("w")),
                     left: env::var("INPUT_GUI_BUTTON_LEFT").unwrap_or(String::from("a")),
                     down: env::var("INPUT_GUI_BUTTON_DOWN").unwrap_or(String::from("s")),
                     right: env::var("INPUT_GUI_BUTTON_RIGHT").unwrap_or(String::from("d")),
                     a: env::var("INPUT_GUI_BUTTON_A").unwrap_or(String::from("1")),
                     b: env::var("INPUT_GUI_BUTTON_B").unwrap_or(String::from("2")),
                     x: env::var("INPUT_GUI_BUTTON_X").unwrap_or(String::from("3")),
                     y: env::var("INPUT_GUI_BUTTON_Y").unwrap_or(String::from("4")),
                     l: env::var("INPUT_GUI_BUTTON_L").unwrap_or(String::from("q")),
                     r: env::var("INPUT_GUI_BUTTON_R").unwrap_or(String::from("e")),
                  },
                  press: PreSufFix{
                     prefix: env::var("INPUT_GUI_PRESS_PREFIX").unwrap_or(String::from("")),
                     suffix: env::var("INPUT_GUI_PRESS_SUFFIX").unwrap_or(String::from("")),
                  },
                  release: PreSufFix{
                     prefix: env::var("INPUT_GUI_RELEASE_PREFIX").unwrap_or(String::from("")),
                     suffix: env::var("INPUT_GUI_RELEASE_SUFFIX").unwrap_or(String::from("")),
                  },
                  user: env::var("INPUT_GUI_USER").unwrap_or(String::from("me")),
                  format: match env::var("INPUT_GUI_FORMAT") {
                     Ok(x) => Some(x),
                     Err(_) => match env::var("INPUT_GUI_FORMAT_V01").unwrap_or(String::from("false")) == String::from("true") {
                        true => Some(String::from("{\"T\":{{ms}},\"U\":\"{{user}}\",\"Y\":\"{{pressed}}\",\"N\":\"{{released}}\"}")),
                        false => None,
                     },
                  },
                  feedback: GUIFeedback{
                     url: match env::var("INPUT_GUI_FEEDBACK_URL") {
                        Ok(url) => Some(url),
                        Err(_) => None,
                     },
                  },
               }),
               device: None,
               udp: Some(UDP{
                  host: Some(env::var("INPUT_UDP_HOST").unwrap_or(String::from("localhost"))),
                  port: env::var("INPUT_UDP_PORT").unwrap_or(String::from("17070")).parse().unwrap(),
               }),
            },
         },
         output: Stream {
            debug: env::var("DEBUG").unwrap_or(String::from("false")) == "true",
            format: match env::var("OUTPUT_FORMAT") {
               Ok(x) => Some(x),
               Err(_) => None,
            },
            engine: Engine{
               name: env::var("OUTPUT_NAME").unwrap_or(String::from("stdout")),
               kafka: None,
               gui: None,
               device: None,
               udp: Some(UDP{
                  host: Some(env::var("OUTPUT_UDP_HOST").unwrap_or(String::from("localhost"))),
                  port: env::var("OUTPUT_UDP_PORT").unwrap_or(String::from("17070")).parse().unwrap(),
               }),
            },
         },
      },
   };
}

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

   #[test]
   fn test_build_config_std() {
      build_config_std();
   }

   #[test]
   fn test_build_config_yaml() {
      build_config_yaml("./src/testdata/config-kinesis-to-kafka.json".to_string()).unwrap();
      build_config_yaml("./src/testdata/config-stdin-to-stdout.yaml".to_string()).unwrap();
   }
}