use crate::domain::repository::{BookFilter, Repository};
use crate::domain::{author, book};
use std::collections::HashMap;
use uuid::Uuid;

#[derive(Clone)]
struct Book {
    id: Uuid,
    title: String,
    author: Vec<String>,
    language: String,
    description: String,
    tags: Vec<String>,
    published_at: String,
    publisher: String,
    updated: String,
}

impl From<book::Book> for Book {
    fn from(book: book::Book) -> Self {
        Book {
            id: book.id,
            title: book.title,
            author: book.author.iter().map(|a| a.id.to_string()).collect(),
            language: book.language,
            description: book.description,
            tags: book.tags,
            published_at: book.published_at,
            publisher: book.publisher,
            updated: book.updated,
        }
    }
}

impl Into<book::Book> for Book {
    fn into(self) -> book::Book {
        book::Book {
            id: self.id,
            title: self.title,
            author: self
                .author
                .iter()
                .map(|a| {
                    let mut na: author::Author = Default::default();
                    if let Ok(id) = Uuid::parse_str(a) {
                        na.id = id;
                    }
                    na
                })
                .collect(),
            language: self.language,
            description: self.description,
            tags: self.tags,
            published_at: self.published_at,
            publisher: self.publisher,
            updated: self.updated,
        }
    }
}

pub struct BookRepository {
    books: Vec<Book>,
    authors: HashMap<Uuid, author::Author>,
    author_uniques: HashMap<String, Uuid>,
}

impl BookRepository {
    pub fn new() -> Self {
        BookRepository {
            books: vec![],
            authors: HashMap::new(),
            author_uniques: HashMap::new(),
        }
    }

    fn populate_authors(&self, book: &mut book::Book) {
        for a in &mut book.author {
            if let Some(stored) = self.authors.get(&a.id) {
                a.first_name = stored.first_name.clone();
                a.last_name = stored.last_name.clone();
                a.middle_name = stored.middle_name.clone();
            }
        }
    }

    fn extract_authors(&mut self, item: &mut book::Book) {
        for a in item.author.iter_mut() {
            let uniq = a.uniq_id().to_string();

            if let Some(&id) = self.author_uniques.get(&uniq) {
                a.id = id;
            } else {
                self.author_uniques.insert(uniq, a.id);
            }

            self.authors.insert(a.id, a.clone());
        }
    }
}

impl Repository<book::Book, BookFilter> for BookRepository {
    fn add(&mut self, mut item: book::Book) {
        if self.get(item.id.to_string()).is_some() {
            return;
        }

        self.extract_authors(&mut item);

        self.books.push(item.into());
    }

    fn bulk_add(&mut self, items: Vec<book::Book>) {
        items.into_iter().for_each(|item| {
            if self.get(item.id.to_string()).is_none() {
                self.add(item)
            }
        });
    }

    fn remove(&mut self, item: book::Book) {
        self.books.retain(|book| book.id != item.id);
    }

    fn get(&self, id: String) -> Option<book::Book> {
        let id_uuid: Uuid = id.parse().unwrap();

        let mut book: Option<book::Book> = self
            .books
            .iter()
            .cloned()
            .find(|x| x.id.eq(&id_uuid))
            .and_then(|x| Some(x.into()));

        if book.is_none() {
            return None;
        }

        if let Some(book) = book.as_mut() {
            self.populate_authors(book);
        }

        book
    }

    fn update(&mut self, mut item: book::Book) {
        self.extract_authors(&mut item);

        for res in &mut self.books {
            if res.id == item.id {
                *res = item.into();

                break;
            }
        }
    }

    fn filter(&self, f: BookFilter) -> Box<dyn Iterator<Item = book::Book>> {
        let mut author_ids: Vec<String> = vec![];
        let mut use_author = false;

        if let Some(author) = f.author {
            if let Some(id) = author.id {
                author_ids.push(id);
                use_author = true;
            }

            if let Some(name) = author.name {
                for (id, author) in self.authors.iter() {
                    if author.first_name.contains(&name)
                        || (author.last_name.is_some()
                            && author.clone().last_name.unwrap().contains(&name))
                        || (author.middle_name.is_some()
                            && author.clone().middle_name.unwrap().contains(&name))
                    {
                        author_ids.push(id.to_string());
                        use_author = true;
                    }
                }
            }
        }

        if author_ids.is_empty() && use_author {
            return Box::new(std::iter::empty::<book::Book>())
        }

        let mut res = self
            .books
            .iter()
            .filter(move |book| {
                // Фильтр по названию
                if let Some(ref search_title) = f.title {
                    if !book.title.contains(search_title) {
                        return false;
                    }
                }
                // Фильтр по описанию
                if let Some(ref descr) = f.description {
                    if !book.description.contains(descr) {
                        return false;
                    }
                }
                // Фильтр по языку
                if let Some(ref lang) = f.language {
                    if !book.language.eq(lang) {
                        return false;
                    }
                }
                // Фильтр по тегам
                if let Some(ref tags) = f.tags {
                    if !tags.iter().all(|tag| book.tags.contains(tag)) {
                        return false;
                    }
                }
                // Фильтр по издателю
                if let Some(ref publisher) = f.publisher {
                    if !book.publisher.eq(publisher) {
                        return false;
                    }
                }
                // Фильтр по датам (пример, можно доработать)
                if let Some(ref published_at) = f.published_at {
                    if book.published_at != *published_at {
                        return false;
                    }
                }
                if let Some(ref updated) = f.updated {
                    if book.updated != *updated {
                        return false;
                    }
                }

                if !author_ids.is_empty() {
                    if !book.author.iter().all(|x| author_ids.contains(x)) {
                        return false;
                    }
                }

                true
            })
            .cloned()
            .map(Into::into)
            .collect::<Vec<book::Book>>();

        for book in &mut res {
            self.populate_authors(book);
        }

        Box::new(res.into_iter())
    }
}