rxing 0.8.2

A rust port of the zxing barcode library.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142

/*
 * Copyright (C) 2012 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;

use crate::{
    common::{BitArray, Result},
    point, BarcodeFormat, Exceptions, RXingResult, RXingResultMetadataType,
    RXingResultMetadataValue,
};

use super::{upc_ean_reader, UPCEANReader, STAND_IN};

/**
 * @see UPCEANExtension5Support
 */
#[derive(Default)]
pub struct UPCEANExtension2Support {
    decodeMiddleCounters: [u32; 4],
}

impl UPCEANExtension2Support {
    pub fn decodeRow(
        &self,
        rowNumber: u32,
        row: &BitArray,
        extensionStartRange: &[u32; 3],
    ) -> Result<RXingResult> {
        let mut result = String::new();
        let end = self.decodeMiddle(row, extensionStartRange, &mut result)?;

        let resultString = result;
        let extensionData = Self::parseExtensionString(&resultString);

        let mut extensionRXingResult = RXingResult::new(
            &resultString,
            Vec::new(),
            vec![
                point(
                    (extensionStartRange[0] + extensionStartRange[1]) as f32 / 2.0,
                    rowNumber as f32,
                ),
                point(end as f32, rowNumber as f32),
            ],
            BarcodeFormat::UPC_EAN_EXTENSION,
        );
        if let Some(ed) = extensionData {
            extensionRXingResult.putAllMetadata(ed);
        }

        Ok(extensionRXingResult)
    }

    fn decodeMiddle(
        &self,
        row: &BitArray,
        startRange: &[u32; 3],
        resultString: &mut String,
    ) -> Result<u32> {
        let mut counters = self.decodeMiddleCounters;
        counters.fill(0);

        let end = row.get_size();
        let mut rowOffset = startRange[1] as usize;

        let mut checkParity = 0;

        let mut x = 0;
        while x < 2 && rowOffset < end {
            // for (int x = 0; x < 2 && rowOffset < end; x++) {
            let bestMatch = STAND_IN.decodeDigit(
                row,
                &mut counters,
                rowOffset,
                &upc_ean_reader::L_AND_G_PATTERNS,
            )?;
            resultString
                .push(char::from_u32('0' as u32 + bestMatch as u32 % 10).ok_or(Exceptions::PARSE)?);

            rowOffset += counters.iter().sum::<u32>() as usize;

            if bestMatch >= 10 {
                checkParity |= 1 << (1 - x);
            }
            if x != 1 {
                // Read off separator if not last
                rowOffset = row.getNextSet(rowOffset);
                rowOffset = row.getNextUnset(rowOffset);
            }
            x += 1;
        }

        if resultString.chars().count() != 2 {
            return Err(Exceptions::NOT_FOUND);
        }

        if resultString
            .parse::<u32>()
            .map_err(|e| Exceptions::parse_with(format!("could not parse {resultString}: {e}")))?
            % 4
            != checkParity
        {
            return Err(Exceptions::NOT_FOUND);
        }

        Ok(rowOffset as u32)
    }

    /**
     * @param raw raw content of extension
     * @return formatted interpretation of raw content as a {@link Map} mapping
     *  one {@link RXingResultMetadataType} to appropriate value, or {@code null} if not known
     */
    fn parseExtensionString(
        raw: &str,
    ) -> Option<HashMap<RXingResultMetadataType, RXingResultMetadataValue>> {
        if raw.chars().count() != 2 {
            return None;
        }
        let mut result = HashMap::new();

        result.insert(
            RXingResultMetadataType::ISSUE_NUMBER,
            RXingResultMetadataValue::IssueNumber(raw.parse::<i32>().ok()?),
        );

        Some(result)
    }
}