stof 0.9.19

Data that carries its own logic.
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

//
// Copyright 2025 Formata, Inc. All rights reserved.
//
// 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::path::Path;
use lopdf::{xobject::PdfImage, Document};
use serde::{Deserialize, Serialize};
use crate::model::StofData;


#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Pdf {
    #[serde(deserialize_with = "deserialize_doc_field")]
    #[serde(serialize_with = "serialize_doc_field")]
    pub doc: Document,
}

#[typetag::serde(name = "Pdf")]
impl StofData for Pdf {}

impl Pdf {
    #[allow(unused)]
    /// Create a PDF from a file.
    pub fn from_file<P: AsRef<Path>>(path: P) -> Result<Self, String> {
        if let Ok(doc) = Document::load(path) {
            return Ok(Self {
                doc,
            });
        }
        Err("could not load the PDF from path".into())
    }

    /// Create a PDF from bytes.
    pub fn from_bytes(bytes: Vec<u8>) -> Result<Self, String> {
        if let Ok(doc) = Document::load_mem(&bytes) {
            return Ok(Self {
                doc,
            });
        }
        Err("could not load PDF from bytes".into())
    }

    #[allow(unused)]
    /// Extract single page text.
    pub fn extract_single_page_text(&self, page: u32) -> Option<String> {
        if let Ok(text) = self.doc.extract_text(&[page]) {
            return Some(text);
        }
        None
    }
    
    /// Extract all text from this PDF document per page.
    pub fn extract_page_text(&self) -> Vec<String> {
        let pages = self.doc.get_pages();
        let mut texts = Vec::new();
        for (i, _) in pages.iter().enumerate() {
            let text = self.doc.extract_text(&[(i + 1) as u32]);
            texts.push(text.unwrap_or_default());
        }
        texts
    }

    /// Extract all text from all pages.
    pub fn extract_text(&self) -> String {
        let mut text = String::default();
        let mut first = true;
        for page in self.extract_page_text() {
            if page.len() > 0 {
                if !first {
                    text.push('\n');
                } else {
                    first = false;
                }
                text.push_str(&page);
            }
        }
        text
    }

    #[allow(unused)]
    /// Extract single page images.
    pub fn extract_single_page_images(&'_ self, page: u32) -> Option<Vec<PdfImage<'_>>> {
        for (i, (_, id)) in self.doc.get_pages().into_iter().enumerate() {
            if (i + 1) as u32 == page {
                if let Ok(page_images) = self.doc.get_page_images(id) {
                    return Some(page_images);
                }
                return None;
            }
        }
        None
    }
    
    /// Extract all images from all pages.
    pub fn extract_images(&'_ self) -> Vec<PdfImage<'_>> {
        let pages = self.doc.get_pages();
        let mut images = Vec::new();
        for (_number, id) in pages.into_iter() {
            if let Ok(mut page_images) = self.doc.get_page_images(id) {
                images.append(&mut page_images);
            }
        }
        images
    }
}

/// Custom serialize for doc field.
fn serialize_doc_field<S>(doc: &Document, serializer: S) -> Result<S::Ok, S::Error>
    where
        S: serde::Serializer {
    let mut data: Vec<u8> = Vec::new();
    let mut mutable = doc.clone();
    let _ = mutable.save_to(&mut data);
    data.serialize(serializer)
}

/// Custom deserialize for data field.
fn deserialize_doc_field<'de, D>(deserializer: D) -> Result<Document, D::Error>
    where
        D: serde::Deserializer<'de> {
    let data: Vec<u8> = Deserialize::deserialize(deserializer)?;
    if let Ok(doc) = Document::load_mem(&data) {
        Ok(doc)
    } else {
        Err(serde::de::Error::custom("could not deserialize Stof PDF document"))
    }
}