use crate::db::Db;
use rhai::plugin::*;
use rhai::{CustomType, Dynamic, Engine, EvalAltResult, Module, Position, TypeBuilder};
use serde::Serialize;
use serde_json;
use std::mem;
use std::sync::Arc;

use super::collection::Collection as RhaiCollection;
use super::items::{
    Book as RhaiBook, Image as RhaiImage, Markdown as RhaiMarkdown, Pdf as RhaiPdf,
    Slide as RhaiSlide, Slideshow as RhaiSlides, TocEntry as RhaiTocEntry,
};
use crate::db::Collection as DbCollectionTrait;
use crate::db::hero::OurDB;

// Helper to convert i64 from Rhai to u32 for IDs
fn id_from_i64_to_u32(id_i64: i64) -> Result<u32, Box<EvalAltResult>> {
    u32::try_from(id_i64).map_err(|_| {
        Box::new(EvalAltResult::ErrorMismatchDataType(
            "u32".to_string(), // Expected type
            format!("i64 value ({}) that cannot be represented as u32", id_i64), // Actual type/value description
            Position::NONE,
        ))
    })
}

/// Registers a `.json()` method for any type `T` that implements the required traits.
fn register_json_method<T>(engine: &mut Engine)
where
    // The type must be:
    T: CustomType + Clone + Serialize, // A clonable, serializable, custom type for Rhai
{
    // This is the function that will be called when a script runs '.json()'
    let to_json_fn = |obj: &mut T| -> Result<String, Box<EvalAltResult>> {
        // Use serde_json to serialize the object to a pretty-formatted string.
        // The '?' will automatically convert any serialization error into a Rhai error.
        serde_json::to_string_pretty(obj).map_err(|e| e.to_string().into())
    };

    // Register the function as a method named "json" for the type 'T'.
    engine.build_type::<T>().register_fn("json", to_json_fn);
}

// Wrapper type for a list of collections to enable .json() method via register_json_method
#[derive(Debug, Clone, Serialize, CustomType)]
#[rhai_type(name = "CollectionArray")]
pub struct RhaiCollectionArray(pub Vec<RhaiCollection>);

impl From<Vec<RhaiCollection>> for RhaiCollectionArray {
    fn from(collections: Vec<RhaiCollection>) -> Self {
        RhaiCollectionArray(collections)
    }
}

#[export_module]
mod rhai_library_module {
    // --- Collection Functions ---
    #[rhai_fn(name = "new_collection")]
    pub fn new_collection() -> RhaiCollection {
        RhaiCollection::new()
    }

    #[rhai_fn(name = "title", return_raw, global, pure)]
    pub fn collection_title(
        collection: &mut RhaiCollection,
        title: String,
    ) -> Result<RhaiCollection, Box<EvalAltResult>> {
        let owned = mem::take(collection);
        *collection = owned.title(title);
        Ok(collection.clone())
    }

    #[rhai_fn(name = "description", return_raw, global, pure)]
    pub fn collection_description(
        collection: &mut RhaiCollection,
        description: String,
    ) -> Result<RhaiCollection, Box<EvalAltResult>> {
        let owned = mem::take(collection);
        *collection = owned.description(description);
        Ok(collection.clone())
    }

    #[rhai_fn(name = "add_image", return_raw, global, pure)]
    pub fn collection_add_image(
        collection: &mut RhaiCollection,
        image_id: i64,
    ) -> Result<RhaiCollection, Box<EvalAltResult>> {
        let id = id_from_i64_to_u32(image_id)?;
        let owned = mem::take(collection);
        *collection = owned.add_image(id);
        Ok(collection.clone())
    }

    #[rhai_fn(name = "add_pdf", return_raw, global, pure)]
    pub fn collection_add_pdf(
        collection: &mut RhaiCollection,
        pdf_id: i64,
    ) -> Result<RhaiCollection, Box<EvalAltResult>> {
        let id = id_from_i64_to_u32(pdf_id)?;
        let owned = mem::take(collection);
        *collection = owned.add_pdf(id);
        Ok(collection.clone())
    }

    #[rhai_fn(name = "add_markdown", return_raw, global, pure)]
    pub fn collection_add_markdown(
        collection: &mut RhaiCollection,
        markdown_id: i64,
    ) -> Result<RhaiCollection, Box<EvalAltResult>> {
        let id = id_from_i64_to_u32(markdown_id)?;
        let owned = mem::take(collection);
        *collection = owned.add_markdown(id);
        Ok(collection.clone())
    }

    #[rhai_fn(name = "add_book", return_raw, global, pure)]
    pub fn collection_add_book(
        collection: &mut RhaiCollection,
        book_id: i64,
    ) -> Result<RhaiCollection, Box<EvalAltResult>> {
        let id = id_from_i64_to_u32(book_id)?;
        let owned = mem::take(collection);
        *collection = owned.add_book(id);
        Ok(collection.clone())
    }

    #[rhai_fn(name = "add_slides", return_raw, global, pure)]
    pub fn collection_add_slides(
        collection: &mut RhaiCollection,
        slides_id: i64,
    ) -> Result<RhaiCollection, Box<EvalAltResult>> {
        let id = id_from_i64_to_u32(slides_id)?;
        let owned = mem::take(collection);
        *collection = owned.add_slides(id);
        Ok(collection.clone())
    }

    #[rhai_fn(get = "id", pure)]
    pub fn get_collection_id(collection: &mut RhaiCollection) -> i64 {
        collection.base_data.id as i64
    }

    #[rhai_fn(get = "created_at", pure)]
    pub fn get_collection_created_at(collection: &mut RhaiCollection) -> i64 {
        collection.base_data.created_at
    }

    #[rhai_fn(get = "modified_at", pure)]
    pub fn get_collection_modified_at(collection: &mut RhaiCollection) -> i64 {
        collection.base_data.modified_at
    }

    #[rhai_fn(get = "title", pure)]
    pub fn get_collection_title(collection: &mut RhaiCollection) -> String {
        collection.title.clone()
    }

    #[rhai_fn(get = "description", pure)]
    pub fn get_collection_description(collection: &mut RhaiCollection) -> Option<String> {
        collection.description.clone()
    }

    #[rhai_fn(get = "images", pure)]
    pub fn get_collection_images(collection: &mut RhaiCollection) -> Vec<i64> {
        collection
            .images
            .clone()
            .into_iter()
            .map(|id| id as i64)
            .collect()
    }

    #[rhai_fn(get = "pdfs", pure)]
    pub fn get_collection_pdfs(collection: &mut RhaiCollection) -> Vec<i64> {
        collection
            .pdfs
            .clone()
            .into_iter()
            .map(|id| id as i64)
            .collect()
    }

    #[rhai_fn(get = "markdowns", pure)]
    pub fn get_collection_markdowns(collection: &mut RhaiCollection) -> Vec<i64> {
        collection
            .markdowns
            .clone()
            .into_iter()
            .map(|id| id as i64)
            .collect()
    }

    #[rhai_fn(get = "books", pure)]
    pub fn get_collection_books(collection: &mut RhaiCollection) -> Vec<i64> {
        collection
            .books
            .clone()
            .into_iter()
            .map(|id| id as i64)
            .collect()
    }

    #[rhai_fn(get = "slides", pure)]
    pub fn get_collection_slides(collection: &mut RhaiCollection) -> Vec<i64> {
        collection
            .slides
            .clone()
            .into_iter()
            .map(|id| id as i64)
            .collect()
    }

    // --- Image Functions ---
    #[rhai_fn(name = "new_image")]
    pub fn new_image() -> RhaiImage {
        RhaiImage::new()
    }

    #[rhai_fn(name = "title", return_raw, global, pure)]
    pub fn image_title(
        image: &mut RhaiImage,
        title: String,
    ) -> Result<RhaiImage, Box<EvalAltResult>> {
        let owned = mem::take(image);
        *image = owned.title(title);
        Ok(image.clone())
    }

    #[rhai_fn(name = "description", return_raw, global, pure)]
    pub fn image_description(
        image: &mut RhaiImage,
        description: String,
    ) -> Result<RhaiImage, Box<EvalAltResult>> {
        let owned = mem::take(image);
        *image = owned.description(description);
        Ok(image.clone())
    }

    #[rhai_fn(name = "url", return_raw, global, pure)]
    pub fn image_url(image: &mut RhaiImage, url: String) -> Result<RhaiImage, Box<EvalAltResult>> {
        let owned = mem::take(image);
        *image = owned.url(url);
        Ok(image.clone())
    }

    #[rhai_fn(name = "width", return_raw, global, pure)]
    pub fn image_width(image: &mut RhaiImage, width: i64) -> Result<RhaiImage, Box<EvalAltResult>> {
        let owned = mem::take(image);
        *image = owned.width(width as u32);
        Ok(image.clone())
    }

    #[rhai_fn(name = "height", return_raw, global, pure)]
    pub fn image_height(
        image: &mut RhaiImage,
        height: i64,
    ) -> Result<RhaiImage, Box<EvalAltResult>> {
        let owned = mem::take(image);
        *image = owned.height(height as u32);
        Ok(image.clone())
    }

    #[rhai_fn(get = "id", pure)]
    pub fn get_image_id(image: &mut RhaiImage) -> i64 {
        image.base_data.id as i64
    }

    #[rhai_fn(get = "created_at", pure)]
    pub fn get_image_created_at(image: &mut RhaiImage) -> i64 {
        image.base_data.created_at
    }

    #[rhai_fn(get = "modified_at", pure)]
    pub fn get_image_modified_at(image: &mut RhaiImage) -> i64 {
        image.base_data.modified_at
    }

    #[rhai_fn(get = "title", pure)]
    pub fn get_image_title(image: &mut RhaiImage) -> String {
        image.title.clone()
    }

    #[rhai_fn(get = "description", pure)]
    pub fn get_image_description(image: &mut RhaiImage) -> Option<String> {
        image.description.clone()
    }

    #[rhai_fn(get = "url", pure)]
    pub fn get_image_url(image: &mut RhaiImage) -> String {
        image.url.clone()
    }

    #[rhai_fn(get = "width", pure)]
    pub fn get_image_width(image: &mut RhaiImage) -> u32 {
        image.width
    }

    #[rhai_fn(get = "height", pure)]
    pub fn get_image_height(image: &mut RhaiImage) -> u32 {
        image.height
    }

    // --- Pdf Functions ---
    #[rhai_fn(name = "new_pdf")]
    pub fn new_pdf() -> RhaiPdf {
        RhaiPdf::new()
    }

    #[rhai_fn(name = "title", return_raw, global, pure)]
    pub fn pdf_title(pdf: &mut RhaiPdf, title: String) -> Result<RhaiPdf, Box<EvalAltResult>> {
        let owned = mem::take(pdf);
        *pdf = owned.title(title);
        Ok(pdf.clone())
    }

    #[rhai_fn(name = "description", return_raw, global, pure)]
    pub fn pdf_description(
        pdf: &mut RhaiPdf,
        description: String,
    ) -> Result<RhaiPdf, Box<EvalAltResult>> {
        let owned = mem::take(pdf);
        *pdf = owned.description(description);
        Ok(pdf.clone())
    }

    #[rhai_fn(name = "url", return_raw, global, pure)]
    pub fn pdf_url(pdf: &mut RhaiPdf, url: String) -> Result<RhaiPdf, Box<EvalAltResult>> {
        let owned = mem::take(pdf);
        *pdf = owned.url(url);
        Ok(pdf.clone())
    }

    #[rhai_fn(name = "page_count", return_raw, global, pure)]
    pub fn pdf_page_count(
        pdf: &mut RhaiPdf,
        page_count: i64,
    ) -> Result<RhaiPdf, Box<EvalAltResult>> {
        let owned = mem::take(pdf);
        *pdf = owned.page_count(page_count as u32);
        Ok(pdf.clone())
    }

    #[rhai_fn(get = "id", pure)]
    pub fn get_pdf_id(pdf: &mut RhaiPdf) -> i64 {
        pdf.base_data.id as i64
    }

    #[rhai_fn(get = "created_at", pure)]
    pub fn get_pdf_created_at(pdf: &mut RhaiPdf) -> i64 {
        pdf.base_data.created_at
    }

    #[rhai_fn(get = "modified_at", pure)]
    pub fn get_pdf_modified_at(pdf: &mut RhaiPdf) -> i64 {
        pdf.base_data.modified_at
    }

    #[rhai_fn(get = "title", pure)]
    pub fn get_pdf_title(pdf: &mut RhaiPdf) -> String {
        pdf.title.clone()
    }

    #[rhai_fn(get = "description", pure)]
    pub fn get_pdf_description(pdf: &mut RhaiPdf) -> Option<String> {
        pdf.description.clone()
    }

    #[rhai_fn(get = "url", pure)]
    pub fn get_pdf_url(pdf: &mut RhaiPdf) -> String {
        pdf.url.clone()
    }

    #[rhai_fn(get = "page_count", pure)]
    pub fn get_pdf_page_count(pdf: &mut RhaiPdf) -> u32 {
        pdf.page_count
    }

    // --- Markdown Functions ---
    #[rhai_fn(name = "new_markdown")]
    pub fn new_markdown() -> RhaiMarkdown {
        RhaiMarkdown::new()
    }

    #[rhai_fn(name = "title", return_raw, global, pure)]
    pub fn markdown_title(
        markdown: &mut RhaiMarkdown,
        title: String,
    ) -> Result<RhaiMarkdown, Box<EvalAltResult>> {
        let owned = mem::take(markdown);
        *markdown = owned.title(title);
        Ok(markdown.clone())
    }

    #[rhai_fn(name = "description", return_raw, global, pure)]
    pub fn markdown_description(
        markdown: &mut RhaiMarkdown,
        description: String,
    ) -> Result<RhaiMarkdown, Box<EvalAltResult>> {
        let owned = mem::take(markdown);
        *markdown = owned.description(description);
        Ok(markdown.clone())
    }

    #[rhai_fn(name = "content", return_raw, global, pure)]
    pub fn markdown_content(
        markdown: &mut RhaiMarkdown,
        content: String,
    ) -> Result<RhaiMarkdown, Box<EvalAltResult>> {
        let owned = mem::take(markdown);
        *markdown = owned.content(content);
        Ok(markdown.clone())
    }

    #[rhai_fn(get = "id", pure)]
    pub fn get_markdown_id(markdown: &mut RhaiMarkdown) -> i64 {
        markdown.base_data.id as i64
    }

    #[rhai_fn(get = "created_at", pure)]
    pub fn get_markdown_created_at(markdown: &mut RhaiMarkdown) -> i64 {
        markdown.base_data.created_at
    }

    #[rhai_fn(get = "modified_at", pure)]
    pub fn get_markdown_modified_at(markdown: &mut RhaiMarkdown) -> i64 {
        markdown.base_data.modified_at
    }

    #[rhai_fn(get = "title", pure)]
    pub fn get_markdown_title(markdown: &mut RhaiMarkdown) -> String {
        markdown.title.clone()
    }

    #[rhai_fn(get = "description", pure)]
    pub fn get_markdown_description(markdown: &mut RhaiMarkdown) -> Option<String> {
        markdown.description.clone()
    }

    #[rhai_fn(get = "content", pure)]
    pub fn get_markdown_content(markdown: &mut RhaiMarkdown) -> String {
        markdown.content.clone()
    }

    // --- TocEntry Functions ---
    #[rhai_fn(name = "new_toc_entry")]
    pub fn new_toc_entry() -> RhaiTocEntry {
        RhaiTocEntry::new()
    }

    #[rhai_fn(name = "title", return_raw, global, pure)]
    pub fn toc_entry_title(
        entry: &mut RhaiTocEntry,
        title: String,
    ) -> Result<RhaiTocEntry, Box<EvalAltResult>> {
        let owned = mem::take(entry);
        *entry = owned.title(title);
        Ok(entry.clone())
    }

    #[rhai_fn(name = "page", return_raw, global, pure)]
    pub fn toc_entry_page(
        entry: &mut RhaiTocEntry,
        page: i64,
    ) -> Result<RhaiTocEntry, Box<EvalAltResult>> {
        let owned = mem::take(entry);
        *entry = owned.page(page as u32);
        Ok(entry.clone())
    }

    #[rhai_fn(name = "add_subsection", return_raw, global, pure)]
    pub fn toc_entry_add_subsection(
        entry: &mut RhaiTocEntry,
        subsection: RhaiTocEntry,
    ) -> Result<RhaiTocEntry, Box<EvalAltResult>> {
        let owned = mem::take(entry);
        *entry = owned.add_subsection(subsection);
        Ok(entry.clone())
    }

    #[rhai_fn(get = "title", pure)]
    pub fn get_toc_entry_title(entry: &mut RhaiTocEntry) -> String {
        entry.title.clone()
    }

    #[rhai_fn(get = "page", pure)]
    pub fn get_toc_entry_page(entry: &mut RhaiTocEntry) -> u32 {
        entry.page
    }

    #[rhai_fn(get = "subsections", pure)]
    pub fn get_toc_entry_subsections(entry: &mut RhaiTocEntry) -> Vec<RhaiTocEntry> {
        entry.subsections.clone()
    }

    // --- Book Functions ---
    #[rhai_fn(name = "new_book")]
    pub fn new_book() -> RhaiBook {
        RhaiBook::new()
    }

    #[rhai_fn(name = "title", return_raw, global, pure)]
    pub fn book_title(book: &mut RhaiBook, title: String) -> Result<RhaiBook, Box<EvalAltResult>> {
        let owned = mem::take(book);
        *book = owned.title(title);
        Ok(book.clone())
    }

    #[rhai_fn(name = "description", return_raw, global, pure)]
    pub fn book_description(
        book: &mut RhaiBook,
        description: String,
    ) -> Result<RhaiBook, Box<EvalAltResult>> {
        let owned = mem::take(book);
        *book = owned.description(description);
        Ok(book.clone())
    }

    #[rhai_fn(name = "add_page", return_raw, global, pure)]
    pub fn book_add_page(
        book: &mut RhaiBook,
        content: String,
    ) -> Result<RhaiBook, Box<EvalAltResult>> {
        let owned = mem::take(book);
        *book = owned.add_page(content);
        Ok(book.clone())
    }

    #[rhai_fn(name = "add_toc_entry", return_raw, global, pure)]
    pub fn book_add_toc_entry(
        book: &mut RhaiBook,
        entry: RhaiTocEntry,
    ) -> Result<RhaiBook, Box<EvalAltResult>> {
        let owned = mem::take(book);
        *book = owned.add_toc_entry(entry);
        Ok(book.clone())
    }

    #[rhai_fn(get = "id", pure)]
    pub fn get_book_id(book: &mut RhaiBook) -> i64 {
        book.base_data.id as i64
    }

    #[rhai_fn(get = "created_at", pure)]
    pub fn get_book_created_at(book: &mut RhaiBook) -> i64 {
        book.base_data.created_at
    }

    #[rhai_fn(get = "modified_at", pure)]
    pub fn get_book_modified_at(book: &mut RhaiBook) -> i64 {
        book.base_data.modified_at
    }

    #[rhai_fn(get = "title", pure)]
    pub fn get_book_title(book: &mut RhaiBook) -> String {
        book.title.clone()
    }

    #[rhai_fn(get = "description", pure)]
    pub fn get_book_description(book: &mut RhaiBook) -> Option<String> {
        book.description.clone()
    }

    #[rhai_fn(get = "table_of_contents", pure)]
    pub fn get_book_table_of_contents(book: &mut RhaiBook) -> Vec<RhaiTocEntry> {
        book.table_of_contents.clone()
    }

    #[rhai_fn(get = "pages", pure)]
    pub fn get_book_pages(book: &mut RhaiBook) -> Vec<String> {
        book.pages.clone()
    }

    // --- Slideshow Functions ---
    #[rhai_fn(name = "new_slide")]
    pub fn new_slide() -> RhaiSlide {
        RhaiSlide::new()
    }

    #[rhai_fn(name = "title", return_raw, global, pure)]
    pub fn slide_title(
        slide: &mut RhaiSlide,
        title: String,
    ) -> Result<RhaiSlide, Box<EvalAltResult>> {
        let owned = mem::take(slide);
        *slide = owned.title(title);
        Ok(slide.clone())
    }

    #[rhai_fn(name = "description", return_raw, global, pure)]
    pub fn slide_description(
        slide: &mut RhaiSlide,
        description: String,
    ) -> Result<RhaiSlide, Box<EvalAltResult>> {
        let owned = mem::take(slide);
        *slide = owned.description(description);
        Ok(slide.clone())
    }

    #[rhai_fn(name = "url", return_raw, global, pure)]
    pub fn slide_url(slide: &mut RhaiSlide, url: String) -> Result<RhaiSlide, Box<EvalAltResult>> {
        let owned = mem::take(slide);
        *slide = owned.url(url);
        Ok(slide.clone())
    }

    // --- Slideshow Functions ---
    #[rhai_fn(name = "new_slides")]
    pub fn new_slides() -> RhaiSlides {
        RhaiSlides::new()
    }

    #[rhai_fn(name = "title", return_raw, global, pure)]
    pub fn slides_title(
        slides: &mut RhaiSlides,
        title: String,
    ) -> Result<RhaiSlides, Box<EvalAltResult>> {
        let owned = mem::take(slides);
        *slides = owned.title(title);
        Ok(slides.clone())
    }

    #[rhai_fn(name = "description", return_raw, global, pure)]
    pub fn slides_description(
        slides: &mut RhaiSlides,
        description: String,
    ) -> Result<RhaiSlides, Box<EvalAltResult>> {
        let owned = mem::take(slides);
        *slides = owned.description(description);
        Ok(slides.clone())
    }

    #[rhai_fn(name = "add_slide", return_raw, global, pure)]
    pub fn slides_add_slide(
        slides: &mut RhaiSlides,
        slide: RhaiSlide,
    ) -> Result<RhaiSlides, Box<EvalAltResult>> {
        let owned = mem::take(slides);
        *slides = owned.add_slide(slide);
        Ok(slides.clone())
    }

    #[rhai_fn(get = "id", pure)]
    pub fn get_slides_id(slides: &mut RhaiSlides) -> i64 {
        slides.base_data.id as i64
    }

    #[rhai_fn(get = "created_at", pure)]
    pub fn get_slides_created_at(slides: &mut RhaiSlides) -> i64 {
        slides.base_data.created_at
    }

    #[rhai_fn(get = "modified_at", pure)]
    pub fn get_slides_modified_at(slides: &mut RhaiSlides) -> i64 {
        slides.base_data.modified_at
    }

    #[rhai_fn(get = "title", pure)]
    pub fn get_slides_title(slides: &mut RhaiSlides) -> String {
        slides.title.clone()
    }

    #[rhai_fn(get = "description", pure)]
    pub fn get_slides_description(slides: &mut RhaiSlides) -> Option<String> {
        slides.description.clone()
    }

    #[rhai_fn(get = "slides", pure)]
    pub fn get_slides_slides(slides: &mut RhaiSlides) -> Vec<RhaiSlide> {
        slides.slides.clone()
    }
}

pub fn register_library_rhai_module(engine: &mut Engine) {
    let module = exported_module!(rhai_library_module);
    engine.register_global_module(module.into());

    let mut db_module = Module::new();

    register_json_method::<RhaiCollection>(engine);
    register_json_method::<RhaiImage>(engine);
    register_json_method::<RhaiPdf>(engine);
    register_json_method::<RhaiMarkdown>(engine);
    register_json_method::<RhaiBook>(engine);
    register_json_method::<RhaiSlides>(engine);
    register_json_method::<RhaiTocEntry>(engine);

    // Register .json() method for our custom CollectionArray type
    register_json_method::<RhaiCollectionArray>(engine);

    // --- Collection DB Functions ---
    let db_clone = db.clone();
    db_module.set_native_fn(
        "save_collection",
        move |collection: RhaiCollection| -> Result<RhaiCollection, Box<EvalAltResult>> {
            let result = db_clone.set(&collection).map_err(|e| {
                Box::new(EvalAltResult::ErrorRuntime(
                    format!("DB Error: {:?}", e).into(),
                    Position::NONE,
                ))
            })?;
            Ok(result.1)
        },
    );

    let db_clone = db.clone();
    db_module.set_native_fn(
        "get_collection",
        move |id: i64| -> Result<RhaiCollection, Box<EvalAltResult>> {
            let collection_id = id_from_i64_to_u32(id)?;
            db_clone
                .get_by_id(collection_id)
                .map_err(|e| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("DB Error: {:?}", e).into(),
                        Position::NONE,
                    ))
                })?
                .ok_or_else(|| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("Collection with ID {} not found", collection_id).into(),
                        Position::NONE,
                    ))
                })
        },
    );

    let db_clone_list_collections = db.clone();
    db_module.set_native_fn(
        "list_collections",
        move || -> Result<RhaiCollectionArray, Box<EvalAltResult>> {
            let collections_vec: Vec<RhaiCollection> = db_clone_list_collections
                .collection::<RhaiCollection>()
                .map_err(|e| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("DB Error (list_collections - access): {:?}", e).into(),
                        Position::NONE,
                    ))
                })?
                .get_all()
                .map_err(|e| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("DB Error (list_collections - get_all): {:?}", e).into(),
                        Position::NONE,
                    ))
                })?;
            Ok(RhaiCollectionArray(collections_vec)) // Wrap in RhaiCollectionArray
        },
    );

    let db_clone = db.clone();
    db_module.set_native_fn(
        "delete_collection",
        move |id: i64| -> Result<(), Box<EvalAltResult>> {
            let collection_id = id_from_i64_to_u32(id)?;
            db_clone
                .collection::<RhaiCollection>()
                .unwrap()
                .delete_by_id(collection_id)
                .map_err(|e| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("DB Error: {:?}", e).into(),
                        Position::NONE,
                    ))
                })?;
            Ok(())
        },
    );

    // --- Image DB Functions ---
    let db_clone = db.clone();
    db_module.set_native_fn(
        "save_image",
        move |image: RhaiImage| -> Result<RhaiImage, Box<EvalAltResult>> {
            let result = db_clone.set(&image).map_err(|e| {
                Box::new(EvalAltResult::ErrorRuntime(
                    format!("DB Error: {:?}", e).into(),
                    Position::NONE,
                ))
            })?;
            Ok(result.1)
        },
    );

    let db_clone = db.clone();
    db_module.set_native_fn(
        "get_image",
        move |id: i64| -> Result<RhaiImage, Box<EvalAltResult>> {
            let image_id = id_from_i64_to_u32(id)?;
            db_clone
                .get_by_id(image_id)
                .map_err(|e| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("DB Error: {:?}", e).into(),
                        Position::NONE,
                    ))
                })?
                .ok_or_else(|| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("Image with ID {} not found", image_id).into(),
                        Position::NONE,
                    ))
                })
        },
    );

    let db_clone = db.clone();
    db_module.set_native_fn(
        "delete_image",
        move |id: i64| -> Result<(), Box<EvalAltResult>> {
            let image_id = id_from_i64_to_u32(id)?;
            db_clone
                .collection::<RhaiImage>()
                .unwrap()
                .delete_by_id(image_id)
                .map_err(|e| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("DB Error: {:?}", e).into(),
                        Position::NONE,
                    ))
                })?;
            Ok(())
        },
    );

    // --- Pdf DB Functions ---
    let db_clone = db.clone();
    db_module.set_native_fn(
        "save_pdf",
        move |pdf: RhaiPdf| -> Result<RhaiPdf, Box<EvalAltResult>> {
            let result = db_clone.set(&pdf).map_err(|e| {
                Box::new(EvalAltResult::ErrorRuntime(
                    format!("DB Error: {:?}", e).into(),
                    Position::NONE,
                ))
            })?;
            Ok(result.1)
        },
    );

    let db_clone = db.clone();
    db_module.set_native_fn(
        "get_pdf",
        move |id: i64| -> Result<RhaiPdf, Box<EvalAltResult>> {
            let pdf_id = id_from_i64_to_u32(id)?;
            db_clone
                .get_by_id(pdf_id)
                .map_err(|e| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("DB Error: {:?}", e).into(),
                        Position::NONE,
                    ))
                })?
                .ok_or_else(|| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("Pdf with ID {} not found", pdf_id).into(),
                        Position::NONE,
                    ))
                })
        },
    );

    let db_clone = db.clone();
    db_module.set_native_fn(
        "delete_pdf",
        move |id: i64| -> Result<(), Box<EvalAltResult>> {
            let pdf_id = id_from_i64_to_u32(id)?;
            db_clone
                .collection::<RhaiPdf>()
                .unwrap()
                .delete_by_id(pdf_id)
                .map_err(|e| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("DB Error: {:?}", e).into(),
                        Position::NONE,
                    ))
                })?;
            Ok(())
        },
    );

    // --- Markdown DB Functions ---
    let db_clone = db.clone();
    db_module.set_native_fn(
        "save_markdown",
        move |markdown: RhaiMarkdown| -> Result<RhaiMarkdown, Box<EvalAltResult>> {
            let result = db_clone.set(&markdown).map_err(|e| {
                Box::new(EvalAltResult::ErrorRuntime(
                    format!("DB Error: {:?}", e).into(),
                    Position::NONE,
                ))
            })?;
            Ok(result.1)
        },
    );

    let db_clone = db.clone();
    db_module.set_native_fn(
        "get_markdown",
        move |id: i64| -> Result<RhaiMarkdown, Box<EvalAltResult>> {
            let markdown_id = id_from_i64_to_u32(id)?;
            db_clone
                .get_by_id(markdown_id)
                .map_err(|e| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("DB Error: {:?}", e).into(),
                        Position::NONE,
                    ))
                })?
                .ok_or_else(|| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("Markdown with ID {} not found", markdown_id).into(),
                        Position::NONE,
                    ))
                })
        },
    );

    let db_clone = db.clone();
    db_module.set_native_fn(
        "delete_markdown",
        move |id: i64| -> Result<(), Box<EvalAltResult>> {
            let markdown_id = id_from_i64_to_u32(id)?;
            db_clone
                .collection::<RhaiMarkdown>()
                .unwrap()
                .delete_by_id(markdown_id)
                .map_err(|e| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("DB Error: {:?}", e).into(),
                        Position::NONE,
                    ))
                })?;
            Ok(())
        },
    );

    // --- Book DB Functions ---
    let db_clone = db.clone();
    db_module.set_native_fn(
        "save_book",
        move |book: RhaiBook| -> Result<RhaiBook, Box<EvalAltResult>> {
            let result = db_clone.set(&book).map_err(|e| {
                Box::new(EvalAltResult::ErrorRuntime(
                    format!("DB Error: {:?}", e).into(),
                    Position::NONE,
                ))
            })?;
            Ok(result.1)
        },
    );

    let db_clone = db.clone();
    db_module.set_native_fn(
        "get_book",
        move |id: i64| -> Result<RhaiBook, Box<EvalAltResult>> {
            let book_id = id_from_i64_to_u32(id)?;
            db_clone
                .get_by_id(book_id)
                .map_err(|e| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("DB Error: {:?}", e).into(),
                        Position::NONE,
                    ))
                })?
                .ok_or_else(|| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("Book with ID {} not found", book_id).into(),
                        Position::NONE,
                    ))
                })
        },
    );

    let db_clone = db.clone();
    db_module.set_native_fn(
        "delete_book",
        move |id: i64| -> Result<(), Box<EvalAltResult>> {
            let book_id = id_from_i64_to_u32(id)?;
            db_clone
                .collection::<RhaiBook>()
                .unwrap()
                .delete_by_id(book_id)
                .map_err(|e| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("DB Error: {:?}", e).into(),
                        Position::NONE,
                    ))
                })?;
            Ok(())
        },
    );

    // --- Slideshow DB Functions ---
    let db_clone = db.clone();
    db_module.set_native_fn(
        "save_slides",
        move |slides: RhaiSlides| -> Result<RhaiSlides, Box<EvalAltResult>> {
            let result = db_clone.set(&slides).map_err(|e| {
                Box::new(EvalAltResult::ErrorRuntime(
                    format!("DB Error: {:?}", e).into(),
                    Position::NONE,
                ))
            })?;
            Ok(result.1)
        },
    );

    let db_clone = db.clone();
    db_module.set_native_fn(
        "get_slides",
        move |id: i64| -> Result<RhaiSlides, Box<EvalAltResult>> {
            let slides_id = id_from_i64_to_u32(id)?;
            db_clone
                .get_by_id(slides_id)
                .map_err(|e| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("DB Error: {:?}", e).into(),
                        Position::NONE,
                    ))
                })?
                .ok_or_else(|| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("Slideshow with ID {} not found", slides_id).into(),
                        Position::NONE,
                    ))
                })
        },
    );

    let db_clone = db.clone();
    db_module.set_native_fn(
        "delete_slides",
        move |id: i64| -> Result<(), Box<EvalAltResult>> {
            let slides_id = id_from_i64_to_u32(id)?;
            db_clone
                .collection::<RhaiSlides>()
                .unwrap()
                .delete_by_id(slides_id)
                .map_err(|e| {
                    Box::new(EvalAltResult::ErrorRuntime(
                        format!("DB Error: {:?}", e).into(),
                        Position::NONE,
                    ))
                })?;
            Ok(())
        },
    );

    engine.register_global_module(db_module.into());
}