strawboat 0.2.6

// 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.

use arrow::array::BooleanArray;
use arrow::bitmap::MutableBitmap;
use arrow::error::Error;

use arrow::error::Result;

use crate::compression::integer::OneValue;

use crate::compression::Compression;
use crate::general_err;

use super::BooleanCompression;

impl BooleanCompression for OneValue {
    fn to_compression(&self) -> Compression {
        Compression::OneValue
    }

    fn compress_ratio(&self, stats: &super::BooleanStats) -> f64 {
        if stats.true_count == 0 || stats.false_count == 0 {
            stats.rows as f64
        } else {
            0.0f64
        }
    }

    fn compress(&self, array: &BooleanArray, output_buf: &mut Vec<u8>) -> Result<usize> {
        let val = array.iter().find(|v| v.is_some());
        let val = match val {
            Some(Some(v)) => v,
            _ => false,
        };
        output_buf.push(val as u8);
        Ok(1)
    }

    fn decompress(&self, input: &[u8], length: usize, output: &mut MutableBitmap) -> Result<()> {
        if input.is_empty() {
            return Err(general_err!("data size is less than {}", 1));
        }
        let val = input[0] > 0;
        output.extend_constant(length, val);
        Ok(())
    }
}