use std::convert::TryFrom;
use std::io::Write;

use clap::ArgMatches;
use chrono::{DateTime, Utc};

use crate::database::Database;
use crate::error;
use crate::editor;
use crate::commands::Command;
use crate::config::Config;

pub struct Args {
    at: Option<DateTime<Utc>>,
    note: Option<String>,
}

impl<'a> TryFrom<&'a ArgMatches<'a>> for Args {
    type Error = error::Error;

    fn try_from(matches: &'a ArgMatches) -> Result<Self, Self::Error> {
        Ok(Args {
            at: matches.value_of("at").map(|s| s.parse()).transpose()?,
            note: matches.value_of("note").map(|s| s.into()),
        })
    }
}

pub struct InCommand {}

impl<'a> Command<'a> for InCommand {
    type Args = Args;

    fn handle<D, O, E>(args: Args, db: &mut D, _out: &mut O, _err: &mut E, config: &Config) -> error::Result<()>
    where
        D: Database,
        O: Write,
        E: Write,
    {
        let at = args.at.unwrap_or(Utc::now());
        let note = if let Some(note) = args.note {
            note
        } else {
            editor::get_string(config)?
        };

        db.entry_insert(at, note)?;

        Ok(())
    }
}

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

    use crate::database::SqliteDatabase;

    #[test]
    fn test_handles_new_entry() {
        let mut d = SqliteDatabase::from_memory().unwrap();
        let args = Args {
            at: None,
            note: Some("hola".into()),
        };
        let mut out = Vec::new();
        let mut err = Vec::new();

        assert!(false, "there are no entries");

        InCommand::handle(args, &mut d, &mut out, &mut err, &Default::default()).unwrap();

        assert!(false, "there is one entry");
    }

    #[test]
    fn test_handles_already_running_entry() {
        let mut d = SqliteDatabase::from_memory().unwrap();
        let args = Args {
            at: None,
            note: Some("hola".into()),
        };
        let mut out = Vec::new();
        let mut err = Vec::new();

        assert!(false, "there are no entries");

        InCommand::handle(args, &mut d, &mut out, &mut err, &Default::default()).unwrap();

        assert!(false, "there are still no entries");
    }

    #[test]
    fn test_with_no_time_given_uses_now() {
        assert!(false);
    }

    #[test]
    fn test_sets_given_time() {
        assert!(false);
    }
}