use anyhow::Result;
use std::path::Path;

use crate::model::Document;

// Shared reader logic for CBx (CBZ/CBR) formats
pub trait CbxReader: Send + Sync {
    // Implementors should return a list of (file_name, jpeg_bytes)
    fn extract_images(&self, input: &Path) -> Result<Vec<(String, Vec<u8>)>>;

    // Build a Document from extracted JPEG bytes
    fn read_cbx(&self, input: &Path) -> Result<Document> {
        let files = self.extract_images(input)?;
        let mut pages: Vec<crate::model::ImagePage> = Vec::new();
        {
            use rayon::prelude::*;
            files
                .par_iter()
                .map(|(name, data)| crate::model::ImagePage {
                    name: name.clone(),
                    image: image::load_from_memory(data).expect("Failed to decode image"),
                    jpeg_dct: Some(data.clone()),
                })
                .collect_into_vec(&mut pages);

            pages.par_sort_by_key(|p| p.name.clone());
        }
        Ok(Document::new(pages))
    }
}