use std::{convert::Infallible, error::Error};

use elefren::{
    helpers::{cli, toml},
    scopes::Scopes,
    status_builder::Visibility,
    Language, Mastodon, MastodonClient, Registration, StatusBuilder,
};

const FEDIVERSE_TOML_PATH: &str = "fediverse.toml";

pub trait Publisher {
    type Error;

    fn publish(&self, content: String) -> Result<(), Self::Error>;
}

pub struct FediversePublisher {
    client: Mastodon,
}

pub struct ConsolePublisher;

impl Publisher for ConsolePublisher {
    type Error = Infallible;

    fn publish(&self, content: String) -> Result<(), Self::Error> {
        println!("Publishing content to stdout: {}", content);
        Ok(())
    }
}

impl ConsolePublisher {
    pub fn new() -> ConsolePublisher {
        ConsolePublisher {}
    }
}

impl FediversePublisher {
    pub fn new(fedi_url: String) -> Result<FediversePublisher, Box<dyn Error>> {
        Ok(Self {
            client: toml::from_file(FEDIVERSE_TOML_PATH)
                .map(|data| Ok(Mastodon::from(data)))
                .unwrap_or_else(|_| register(fedi_url))?,
        })
    }
}

impl Publisher for FediversePublisher {
    type Error = Box<dyn Error>;

    fn publish(&self, content: String) -> Result<(), Self::Error> {
        let status = StatusBuilder::new()
            .status(&content)
            // .visibility(Visibility::Direct)
            .visibility(Visibility::Public)
            .sensitive(false)
            .language(Language::Eng)
            .build()
            .map_err(|e| Box::new(e) as Box<dyn Error>)?;

        println!("Posting status [{}] to fediverse", &content);

        self.client
            .new_status(status)
            .map_err(|e| Box::new(e) as Box<dyn Error>)?;

        Ok(())
    }
}

fn register(fedi_url: String) -> Result<Mastodon, Box<dyn Error>> {
    let registration = Registration::new(fedi_url)
        .client_name("izzilis")
        .scopes(Scopes::write_all())
        .build()?;
    let fediverse = cli::authenticate(registration)?;

    // Save app data for using on the next run.
    toml::to_file(&*fediverse, FEDIVERSE_TOML_PATH.to_string())?;

    Ok(fediverse)
}