epub.rs

1 files changed, 195 insertions, 0 deletions

diff --git a/src/epub.rs b/src/epub.rs
new file mode 100644
index 0000000..508e6b1
--- /dev/null
+++ b/src/epub.rs
@@ -0,0 +1,195 @@
+use std::collections::HashMap;
+use std::fs::File;
+use std::io::Read;
+
+use roxmltree::{Document, Node};
+
+pub struct Epub {
+    container: zip::ZipArchive<File>,
+    pub nav: Vec<String>,
+    pub pages: Vec<Vec<String>>,
+}
+
+impl Epub {
+    pub fn new(path: &str) -> std::io::Result<Self> {
+        let file = File::open(path)?;
+        let mut epub = Epub {
+            container: zip::ZipArchive::new(file)?,
+            nav: Vec::new(),
+            pages: Vec::new(),
+        };
+        let nav = epub.get_nav();
+        epub.nav.reserve_exact(nav.len());
+        epub.pages.reserve_exact(nav.len());
+        for (path, label) in nav {
+            epub.nav.push(label);
+            let xml = epub.get_text(&path);
+            let doc = Document::parse(&xml).unwrap();
+            let body = doc.root_element().last_element_child().unwrap();
+            let mut page = Vec::new();
+            Epub::render(&mut page, body);
+            epub.pages.push(page);
+        }
+        Ok(epub)
+    }
+    fn render(buf: &mut Vec<String>, n: Node) {
+        if n.is_text() {
+            let text = n.text().unwrap();
+            if !text.trim().is_empty() {
+                let last = buf.last_mut().unwrap();
+                last.push_str(text);
+            }
+            return;
+        }
+
+        match n.tag_name().name() {
+            "h1" | "h2" | "h3" | "h4" | "h5" | "h6" => {
+                buf.push(String::from("\x1b\x5b1m"));
+                for c in n.children() {
+                    Self::render(buf, c);
+                }
+                buf.push(String::from("\x1b\x5b0m"));
+            }
+            "blockquote" | "p" => {
+                buf.push(String::new());
+                for c in n.children() {
+                    Self::render(buf, c);
+                }
+                buf.push(String::new());
+            }
+            "li" => {
+                buf.push(String::from("- "));
+                for c in n.children() {
+                    Self::render(buf, c);
+                }
+                buf.push(String::new());
+            }
+            "br" => buf.push(String::new()),
+            _ => {
+                for c in n.children() {
+                    Self::render(buf, c);
+                }
+            }
+        }
+    }
+    fn get_text(&mut self, name: &str) -> String {
+        let mut text = String::new();
+        self.container
+            .by_name(name)
+            .unwrap()
+            .read_to_string(&mut text)
+            .unwrap();
+        text
+    }
+    fn get_nav(&mut self) -> Vec<(String, String)> {
+        let xml = self.get_text("META-INF/container.xml");
+        let doc = Document::parse(&xml).unwrap();
+        let path = doc
+            .descendants()
+            .find(|n| n.has_tag_name("rootfile"))
+            .unwrap()
+            .attribute("full-path")
+            .unwrap();
+
+        let xml = self.get_text(path);
+        let doc = Document::parse(&xml).unwrap();
+        let rootdir = std::path::Path::new(&path).parent().unwrap();
+
+        let mut manifest = HashMap::new();
+        doc.root_element()
+            .children()
+            .find(|n| n.has_tag_name("manifest"))
+            .unwrap()
+            .children()
+            .filter(Node::is_element)
+            .for_each(|n| {
+                manifest.insert(n.attribute("id").unwrap(), n.attribute("href").unwrap());
+            });
+
+        // TODO check if epub3 nav is reliable w/o spine
+        let mut nav = HashMap::new();
+        if doc.root_element().attribute("version") == Some("3.0") {
+            let path = doc
+                .root_element()
+                .children()
+                .find(|n| n.has_tag_name("manifest"))
+                .unwrap()
+                .children()
+                .find(|n| n.attribute("properties") == Some("nav"))
+                .unwrap()
+                .attribute("href")
+                .unwrap();
+            let xml = self.get_text(rootdir.join(path).to_str().unwrap());
+            let doc = Document::parse(&xml).unwrap();
+
+            doc.descendants()
+                .find(|n| n.has_tag_name("nav"))
+                .unwrap()
+                .descendants()
+                .filter(|n| n.has_tag_name("a"))
+                .for_each(|n| {
+                    let path = n.attribute("href").unwrap().to_string();
+                    let text = n
+                        .descendants()
+                        .filter(Node::is_text)
+                        .map(|n| n.text().unwrap())
+                        .collect();
+                    nav.insert(path, text);
+                })
+        } else {
+            let path = manifest.get("ncx").unwrap();
+            let xml = self.get_text(rootdir.join(path).to_str().unwrap());
+            let doc = Document::parse(&xml).unwrap();
+
+            doc.descendants()
+                .find(|n| n.has_tag_name("navMap"))
+                .unwrap()
+                .descendants()
+                .filter(|n| n.has_tag_name("navPoint"))
+                .for_each(|n| {
+                    let path = n
+                        .descendants()
+                        .find(|n| n.has_tag_name("content"))
+                        .unwrap()
+                        .attribute("src")
+                        .unwrap()
+                        .to_string();
+                    let text = n
+                        .descendants()
+                        .find(|n| n.has_tag_name("text"))
+                        .unwrap()
+                        .text()
+                        .unwrap()
+                        .to_string();
+                    nav.insert(path, text);
+                })
+        }
+
+        doc.root_element()
+            .children()
+            .find(|n| n.has_tag_name("spine"))
+            .unwrap()
+            .children()
+            .filter(Node::is_element)
+            .enumerate()
+            .map(|(i, n)| {
+                let id = n.attribute("idref").unwrap();
+                let path = manifest.remove(id).unwrap();
+                let label = nav.remove(path).unwrap_or_else(|| i.to_string());
+                let path = rootdir.join(path).to_str().unwrap().to_string();
+                (path, label)
+            })
+            .collect()
+    }
+}
+
+#[test]
+fn test_dir() {
+    let path = "/mnt/lit/read";
+    for entry in std::fs::read_dir(path).unwrap() {
+        let path = entry.unwrap().path();
+        let s = path.to_str().unwrap();
+        println!("testing: {}", s);
+        Epub::new(s).unwrap();
+    }
+}