/*
 * Copyright 2007 ZXing authors
 *
 * Licensed 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 std::collections::{HashMap, HashSet};

use crate::common::Result;
use crate::{
    aztec::AztecReader, datamatrix::DataMatrixReader, maxicode::MaxiCodeReader,
    oned::MultiFormatOneDReader, pdf417::PDF417Reader, qrcode::QRCodeReader, BarcodeFormat,
    Binarizer, BinaryBitmap, DecodeHintType, DecodeHintValue, DecodingHintDictionary, Exceptions,
    RXingResult, Reader,
};

/**
 * MultiFormatReader is a convenience class and the main entry point into the library for most uses.
 * By default it attempts to decode all barcode formats that the library supports. Optionally, you
 * can provide a hints object to request different behavior, for example only decoding QR codes.
 *
 * @author Sean Owen
 * @author dswitkin@google.com (Daniel Switkin)
 */
#[derive(Default)]
pub struct MultiFormatReader {
    hints: DecodingHintDictionary,
    possible_formats: HashSet<BarcodeFormat>,
    try_harder: bool,
    one_d_reader: MultiFormatOneDReader,
}

impl Reader for MultiFormatReader {
    /**
     * This version of decode honors the intent of Reader.decode(BinaryBitmap) in that it
     * passes null as a hint to the decoders. However, that makes it inefficient to call repeatedly.
     * Use setHints() followed by decodeWithState() for continuous scan applications.
     *
     * @param image The pixel data to decode
     * @return The contents of the image
     * @throws NotFoundException Any errors which occurred
     */
    fn decode<B: Binarizer>(&mut self, image: &mut BinaryBitmap<B>) -> Result<RXingResult> {
        self.set_hints(&HashMap::new());
        self.decode_internal(image)
    }

    /**
     * Decode an image using the hints provided. Does not honor existing state.
     *
     * @param image The pixel data to decode
     * @param hints The hints to use, clearing the previous state.
     * @return The contents of the image
     * @throws NotFoundException Any errors which occurred
     */
    fn decode_with_hints<B: Binarizer>(
        &mut self,
        image: &mut BinaryBitmap<B>,
        hints: &DecodingHintDictionary,
    ) -> Result<RXingResult> {
        self.set_hints(hints);
        self.decode_internal(image)
    }

    fn reset(&mut self) {
        self.one_d_reader.reset();
    }
}

impl MultiFormatReader {
    /**
     * Decode an image using the state set up by calling setHints() previously. Continuous scan
     * clients will get a <b>large</b> speed increase by using this instead of decode().
     *
     * @param image The pixel data to decode
     * @return The contents of the image
     * @throws NotFoundException Any errors which occurred
     */
    pub fn decode_with_state<B: Binarizer>(
        &mut self,
        image: &mut BinaryBitmap<B>,
    ) -> Result<RXingResult> {
        // Make sure to set up the default state so we don't crash
        if self.possible_formats.is_empty() {
            self.set_hints(&HashMap::new());
        }
        self.decode_internal(image)
    }

    /**
     * This method adds state to the MultiFormatReader. By setting the hints once, subsequent calls
     * to decodeWithState(image) can reuse the same set of readers without reallocating memory. This
     * is important for performance in continuous scan clients.
     *
     * @param hints The set of hints to use for subsequent calls to decode(image)
     */
    pub fn set_hints(&mut self, hints: &DecodingHintDictionary) {
        self.hints = hints.clone();

        self.try_harder = matches!(
            self.hints.get(&DecodeHintType::TRY_HARDER),
            Some(DecodeHintValue::TryHarder(true))
        );
        self.possible_formats = if let Some(DecodeHintValue::PossibleFormats(formats)) =
            hints.get(&DecodeHintType::POSSIBLE_FORMATS)
        {
            formats.clone()
        } else {
            HashSet::new()
        };
        self.one_d_reader = MultiFormatOneDReader::new(hints);
    }

    pub fn decode_internal<B: Binarizer>(
        &mut self,
        image: &mut BinaryBitmap<B>,
    ) -> Result<RXingResult> {
        let res = self.decode_formats(image);
        if res.is_ok() {
            return res;
        }
        if matches!(
            self.hints.get(&DecodeHintType::ALSO_INVERTED),
            Some(DecodeHintValue::AlsoInverted(true))
        ) {
            // Calling all readers again with inverted image
            image.get_black_matrix_mut().flip_self();
            let res = self.decode_formats(image);
            if res.is_ok() {
                return res;
            }
        }
        Err(Exceptions::NOT_FOUND)
    }

    fn decode_formats<B: Binarizer>(&mut self, image: &mut BinaryBitmap<B>) -> Result<RXingResult> {
        if !self.possible_formats.is_empty() {
            let one_d = self.possible_formats.contains(&BarcodeFormat::UPC_A)
                || self.possible_formats.contains(&BarcodeFormat::UPC_E)
                || self.possible_formats.contains(&BarcodeFormat::EAN_13)
                || self.possible_formats.contains(&BarcodeFormat::EAN_8)
                || self.possible_formats.contains(&BarcodeFormat::CODABAR)
                || self.possible_formats.contains(&BarcodeFormat::CODE_39)
                || self.possible_formats.contains(&BarcodeFormat::CODE_93)
                || self.possible_formats.contains(&BarcodeFormat::CODE_128)
                || self.possible_formats.contains(&BarcodeFormat::ITF)
                || self.possible_formats.contains(&BarcodeFormat::RSS_14)
                || self.possible_formats.contains(&BarcodeFormat::RSS_EXPANDED);
            if one_d && !self.try_harder {
                if let Ok(res) = self.one_d_reader.decode_with_hints(image, &self.hints) {
                    return Ok(res);
                }
            }
            for possible_format in self.possible_formats.iter() {
                let res = match possible_format {
                    BarcodeFormat::QR_CODE => {
                        QRCodeReader::default().decode_with_hints(image, &self.hints)
                    }
                    BarcodeFormat::DATA_MATRIX => {
                        DataMatrixReader::default().decode_with_hints(image, &self.hints)
                    }
                    BarcodeFormat::AZTEC => {
                        AztecReader::default().decode_with_hints(image, &self.hints)
                    }
                    BarcodeFormat::PDF_417 => {
                        PDF417Reader::default().decode_with_hints(image, &self.hints)
                    }
                    BarcodeFormat::MAXICODE => {
                        MaxiCodeReader::default().decode_with_hints(image, &self.hints)
                    }
                    _ => Err(Exceptions::UNSUPPORTED_OPERATION),
                };
                if res.is_ok() {
                    return res;
                }
            }
            if one_d && self.try_harder {
                if let Ok(res) = self.one_d_reader.decode_with_hints(image, &self.hints) {
                    return Ok(res);
                }
            }
        } else {
            if !self.try_harder {
                if let Ok(res) = self.one_d_reader.decode_with_hints(image, &self.hints) {
                    return Ok(res);
                }
            }

            if let Ok(res) = QRCodeReader::default().decode_with_hints(image, &self.hints) {
                return Ok(res);
            }
            if let Ok(res) = DataMatrixReader::default().decode_with_hints(image, &self.hints) {
                return Ok(res);
            }
            if let Ok(res) = AztecReader::default().decode_with_hints(image, &self.hints) {
                return Ok(res);
            }
            if let Ok(res) = PDF417Reader::default().decode_with_hints(image, &self.hints) {
                return Ok(res);
            }
            if let Ok(res) = MaxiCodeReader::default().decode_with_hints(image, &self.hints) {
                return Ok(res);
            }

            if self.try_harder {
                if let Ok(res) = self.one_d_reader.decode_with_hints(image, &self.hints) {
                    return Ok(res);
                }
            }
        }

        Err(Exceptions::UNSUPPORTED_OPERATION)
    }
}