// Copyright (C) 2017 Sebastian Dröge <sebastian@centricular.com>
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

use std::fmt;
use DateTime;

impl fmt::Display for DateTime {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        f.write_str(
            self.to_iso8601_string()
                .unwrap_or_else(|| String::from("None"))
                .as_str(),
        )
    }
}

#[cfg(feature = "ser_de")]
pub(crate) mod serde {
    use serde::de::{Deserialize, Deserializer};
    use serde::ser::{Serialize, Serializer, SerializeStruct};
    use DateTime;

    impl<'a> Serialize for DateTime {
        fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
            let mut datetime = serializer.serialize_struct("DateTime", 8)?;
            datetime.serialize_field("tz_offset", &self.get_time_zone_offset())?;
            datetime.serialize_field("y", &self.get_year())?;
            datetime.serialize_field("m", &self.get_month())?;
            datetime.serialize_field("d", &self.get_day())?;
            datetime.serialize_field("h", &self.get_hour())?;
            datetime.serialize_field("mn", &self.get_minute())?;
            datetime.serialize_field("s", &self.get_second())?;
            datetime.serialize_field("us", &self.get_microsecond())?;
            datetime.end()
        }
    }

    #[derive(Deserialize)]
    struct DateTimeDe {
        tz_offset: f32,
        y: i32,
        m: i32,
        d: i32,
        h: i32,
        mn: i32,
        s: i32,
        us: i32,
    }

    impl From<DateTimeDe> for DateTime {
        fn from(dt_de: DateTimeDe) -> Self {
            ::DateTime::new(
                dt_de.tz_offset,
                dt_de.y,
                dt_de.m,
                dt_de.d,
                dt_de.h,
                dt_de.mn,
                f64::from(dt_de.s) + f64::from(dt_de.us) / 1_000_000f64,
            )
        }
    }

    impl<'de> Deserialize<'de> for DateTime {
        fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
            DateTimeDe::deserialize(deserializer)
                .and_then(|datetime_de| Ok(datetime_de.into()))
        }
    }
}

#[cfg(test)]
mod tests {
    #[cfg(feature = "ser_de")]
    #[test]
    fn test_serialize() {
        extern crate ron;
        extern crate serde_json;

        use DateTime;

        ::init().unwrap();

        let datetime = DateTime::new(2f32, 2018, 5, 28, 16, 6, 42.841f64);

        // don't use newlines
        let mut pretty_config = ron::ser::PrettyConfig::default();
        pretty_config.new_line = "".to_string();

        let res = ron::ser::to_string_pretty(&datetime, pretty_config);
        assert_eq!(
            Ok(
                concat!(
                    "(",
                    "    tz_offset: 2,",
                    "    y: 2018,",
                    "    m: 5,",
                    "    d: 28,",
                    "    h: 16,",
                    "    mn: 6,",
                    "    s: 42,",
                    "    us: 841000,",
                    ")"
                )
                    .to_owned()
            ),
            res,
        );

        let res = serde_json::to_string(&datetime).unwrap();
        assert_eq!(
            "{\"tz_offset\":2.0,\"y\":2018,\"m\":5,\"d\":28,\"h\":16,\"mn\":6,\"s\":42,\"us\":841000}"
                .to_owned(),
            res,
        );
    }

    #[cfg(feature = "ser_de")]
    #[test]
    fn test_deserialize() {
        extern crate ron;
        extern crate serde_json;

        use DateTime;

        ::init().unwrap();

        let datetime_ron = r#"
            (
                tz_offset: 2,
                y: 2018,
                m: 5,
                d: 28,
                h: 16,
                mn: 6,
                s: 42,
                us: 841000,
            )
        "#;
        let datetime: DateTime = ron::de::from_str(datetime_ron).unwrap();
        assert_eq!(datetime.get_time_zone_offset(), 2f32);
        assert_eq!(datetime.get_year(), 2018);
        assert_eq!(datetime.get_month(), 5);
        assert_eq!(datetime.get_day(), 28);
        assert_eq!(datetime.get_hour(), 16);
        assert_eq!(datetime.get_minute(), 6);
        assert_eq!(datetime.get_second(), 42);
        assert_eq!(datetime.get_microsecond(), 841_000);

        let datetime_json = r#"
            {"tz_offset":2.0,"y":2018,"m":5,"d":28,"h":16,"mn":6,"s":42,"us":841000}
        "#;
        let datetime: DateTime = serde_json::from_str(datetime_json).unwrap();
        assert_eq!(datetime.get_time_zone_offset(), 2f32);
        assert_eq!(datetime.get_year(), 2018);
        assert_eq!(datetime.get_month(), 5);
        assert_eq!(datetime.get_day(), 28);
        assert_eq!(datetime.get_hour(), 16);
        assert_eq!(datetime.get_minute(), 6);
        assert_eq!(datetime.get_second(), 42);
        assert_eq!(datetime.get_microsecond(), 841_000);
    }
}