// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.

//! date & time DataFusion functions

use std::sync::Arc;

use datafusion_expr::ScalarUDF;

pub mod common;
pub mod current_date;
pub mod current_time;
pub mod date_bin;
pub mod date_part;
pub mod date_trunc;
pub mod from_unixtime;
pub mod make_date;
pub mod now;
pub mod to_char;
pub mod to_date;
pub mod to_timestamp;
pub mod to_unixtime;

// create UDFs
make_udf_function!(current_date::CurrentDateFunc, CURRENT_DATE, current_date);
make_udf_function!(current_time::CurrentTimeFunc, CURRENT_TIME, current_time);
make_udf_function!(date_bin::DateBinFunc, DATE_BIN, date_bin);
make_udf_function!(date_part::DatePartFunc, DATE_PART, date_part);
make_udf_function!(date_trunc::DateTruncFunc, DATE_TRUNC, date_trunc);
make_udf_function!(make_date::MakeDateFunc, MAKE_DATE, make_date);
make_udf_function!(
    from_unixtime::FromUnixtimeFunc,
    FROM_UNIXTIME,
    from_unixtime
);
make_udf_function!(now::NowFunc, NOW, now);
make_udf_function!(to_char::ToCharFunc, TO_CHAR, to_char);
make_udf_function!(to_date::ToDateFunc, TO_DATE, to_date);
make_udf_function!(to_unixtime::ToUnixtimeFunc, TO_UNIXTIME, to_unixtime);
make_udf_function!(to_timestamp::ToTimestampFunc, TO_TIMESTAMP, to_timestamp);
make_udf_function!(
    to_timestamp::ToTimestampSecondsFunc,
    TO_TIMESTAMP_SECONDS,
    to_timestamp_seconds
);
make_udf_function!(
    to_timestamp::ToTimestampMillisFunc,
    TO_TIMESTAMP_MILLIS,
    to_timestamp_millis
);
make_udf_function!(
    to_timestamp::ToTimestampMicrosFunc,
    TO_TIMESTAMP_MICROS,
    to_timestamp_micros
);
make_udf_function!(
    to_timestamp::ToTimestampNanosFunc,
    TO_TIMESTAMP_NANOS,
    to_timestamp_nanos
);

// we cannot currently use the export_functions macro since it doesn't handle
// functions with varargs currently

pub mod expr_fn {
    use datafusion_expr::Expr;

    #[doc = "returns current UTC date as a Date32 value"]
    pub fn current_date() -> Expr {
        super::current_date().call(vec![])
    }

    #[doc = "returns current UTC time as a Time64 value"]
    pub fn current_time() -> Expr {
        super::current_time().call(vec![])
    }

    #[doc = "coerces an arbitrary timestamp to the start of the nearest specified interval"]
    pub fn date_bin(stride: Expr, source: Expr, origin: Expr) -> Expr {
        super::date_bin().call(vec![stride, source, origin])
    }

    #[doc = "extracts a subfield from the date"]
    pub fn date_part(part: Expr, date: Expr) -> Expr {
        super::date_part().call(vec![part, date])
    }

    #[doc = "truncates the date to a specified level of precision"]
    pub fn date_trunc(part: Expr, date: Expr) -> Expr {
        super::date_trunc().call(vec![part, date])
    }

    #[doc = "converts an integer to RFC3339 timestamp format string"]
    pub fn from_unixtime(unixtime: Expr) -> Expr {
        super::from_unixtime().call(vec![unixtime])
    }

    #[doc = "make a date from year, month and day component parts"]
    pub fn make_date(year: Expr, month: Expr, day: Expr) -> Expr {
        super::make_date().call(vec![year, month, day])
    }

    #[doc = "returns the current timestamp in nanoseconds, using the same value for all instances of now() in same statement"]
    pub fn now() -> Expr {
        super::now().call(vec![])
    }

    /// Returns a string representation of a date, time, timestamp or duration based
    /// on a Chrono pattern.
    ///
    /// The syntax for the patterns can be found at
    /// <https://docs.rs/chrono/latest/chrono/format/strftime/index.html>
    ///
    /// # Examples
    ///
    /// ```ignore
    /// # use chrono::prelude::*;
    /// # use datafusion::prelude::*;
    /// # use datafusion::error::Result;
    /// # use datafusion_common::ScalarValue::TimestampNanosecond;
    /// # use std::sync::Arc;
    /// # use arrow_array::{Date32Array, RecordBatch, StringArray};
    /// # use arrow_schema::{DataType, Field, Schema};
    /// # #[tokio::main]
    /// # async fn main() -> Result<()> {
    /// let schema = Arc::new(Schema::new(vec![
    ///     Field::new("values", DataType::Date32, false),
    ///     Field::new("patterns", DataType::Utf8, false),
    /// ]));
    ///
    /// let batch = RecordBatch::try_new(
    ///     schema,
    ///     vec![
    ///         Arc::new(Date32Array::from(vec![
    ///             18506,
    ///             18507,
    ///             18508,
    ///             18509,
    ///         ])),
    ///         Arc::new(StringArray::from(vec![
    ///             "%Y-%m-%d",
    ///             "%Y:%m:%d",
    ///             "%Y%m%d",
    ///             "%d-%m-%Y",
    ///         ])),
    ///     ],
    /// )?;
    ///
    /// let ctx = SessionContext::new();
    /// ctx.register_batch("t", batch)?;
    /// let df = ctx.table("t").await?;
    ///
    /// // use the to_char function to convert col 'values',
    /// // to strings using patterns in col 'patterns'
    /// let df = df.with_column(
    ///     "date_str",
    ///     to_char(col("values"), col("patterns"))
    /// )?;
    /// // Note that providing a scalar value for the pattern
    /// // is more performant
    /// let df = df.with_column(
    ///     "date_str2",
    ///     to_char(col("values"), lit("%d-%m-%Y"))
    /// )?;
    /// // literals can be used as well with dataframe calls
    /// let timestamp = "2026-07-08T09:10:11"
    ///     .parse::<NaiveDateTime>()
    ///     .unwrap()
    ///     .with_nanosecond(56789)
    ///     .unwrap()
    ///     .timestamp_nanos_opt()
    ///     .unwrap();
    /// let df = df.with_column(
    ///     "timestamp_str",
    ///     to_char(lit(TimestampNanosecond(Some(timestamp), None)), lit("%d-%m-%Y %H:%M:%S"))
    /// )?;
    ///
    /// df.show().await?;
    ///
    /// # Ok(())
    /// # }
    /// ```
    pub fn to_char(datetime: Expr, format: Expr) -> Expr {
        super::to_char().call(vec![datetime, format])
    }

    /// ```ignore
    /// # use std::sync::Arc;
    ///
    /// # use datafusion_common::Result;
    ///
    /// # #[tokio::main]
    /// # async fn main() -> Result<()> {
    /// #  use arrow::array::StringArray;
    /// #  use arrow::datatypes::{DataType, Field, Schema};
    /// #  use arrow::record_batch::RecordBatch;
    /// #  use datafusion_expr::col;
    /// #  use datafusion::prelude::*;
    /// #  use datafusion_functions::expr_fn::to_date;
    ///
    ///     // define a schema.
    ///     let schema = Arc::new(Schema::new(vec![Field::new("a", DataType::Utf8, false)]));
    ///
    ///     // define data.
    ///     let batch = RecordBatch::try_new(
    ///         schema,
    ///         vec![Arc::new(StringArray::from(vec![
    ///             "2020-09-08T13:42:29Z",
    ///             "2020-09-08T13:42:29.190855-05:00",
    ///             "2020-08-09 12:13:29",
    ///             "2020-01-02",
    ///         ]))],
    ///     )?;
    ///
    ///     // declare a new context. In spark API, this corresponds to a new spark SQLsession
    ///     let ctx = SessionContext::new();
    ///
    ///     // declare a table in memory. In spark API, this corresponds to createDataFrame(...).
    ///     ctx.register_batch("t", batch)?;
    ///     let df = ctx.table("t").await?;
    ///
    ///     // use to_date function to convert col 'a' to timestamp type using the default parsing
    ///     let df = df.with_column("a", to_date(vec![col("a")]))?;
    ///
    ///     let df = df.select_columns(&["a"])?;
    ///
    ///     // print the results
    ///     df.show().await?;
    ///
    ///     # Ok(())
    /// # }
    /// ```
    pub fn to_date(args: Vec<Expr>) -> Expr {
        super::to_date().call(args)
    }

    #[doc = "converts a string and optional formats to a Unixtime"]
    pub fn to_unixtime(args: Vec<Expr>) -> Expr {
        super::to_unixtime().call(args)
    }

    #[doc = "converts a string and optional formats to a `Timestamp(Nanoseconds, None)`"]
    pub fn to_timestamp(args: Vec<Expr>) -> Expr {
        super::to_timestamp().call(args)
    }

    #[doc = "converts a string and optional formats to a `Timestamp(Seconds, None)`"]
    pub fn to_timestamp_seconds(args: Vec<Expr>) -> Expr {
        super::to_timestamp_seconds().call(args)
    }

    #[doc = "converts a string and optional formats to a `Timestamp(Milliseconds, None)`"]
    pub fn to_timestamp_millis(args: Vec<Expr>) -> Expr {
        super::to_timestamp_millis().call(args)
    }

    #[doc = "converts a string and optional formats to a `Timestamp(Microseconds, None)`"]
    pub fn to_timestamp_micros(args: Vec<Expr>) -> Expr {
        super::to_timestamp_micros().call(args)
    }

    #[doc = "converts a string and optional formats to a `Timestamp(Nanoseconds, None)`"]
    pub fn to_timestamp_nanos(args: Vec<Expr>) -> Expr {
        super::to_timestamp_nanos().call(args)
    }
}

///   Return a list of all functions in this package
pub fn functions() -> Vec<Arc<ScalarUDF>> {
    vec![
        current_date(),
        current_time(),
        date_bin(),
        date_part(),
        date_trunc(),
        from_unixtime(),
        make_date(),
        now(),
        to_char(),
        to_date(),
        to_unixtime(),
        to_timestamp(),
        to_timestamp_seconds(),
        to_timestamp_millis(),
        to_timestamp_micros(),
        to_timestamp_nanos(),
    ]
}