use crate::addressing::Address;
use crate::database::{
    insert_entry, query, remove_object, retrieve_file, retrieve_object, DbPool, Entry, Query,
};
use crate::filesystem::{list_directory, lookup_by_filename, UPath};
use crate::hash::{decode, encode, Hashable};
use actix_files::NamedFile;
use actix_web::error::{ErrorBadRequest, ErrorInternalServerError, ErrorNotFound};
use actix_web::{delete, error, get, post, put, web, Error, HttpResponse};
use anyhow::Result;
use futures_util::StreamExt;
use log::debug;
use serde::Deserialize;
use std::collections::HashMap;
use std::path::PathBuf;

#[derive(Clone)]
pub struct State {
    pub directory: PathBuf,
    pub db_pool: DbPool,
}

#[get("/api/raw/{hash}")]
pub async fn get_raw(state: web::Data<State>, hash: web::Path<String>) -> Result<NamedFile, Error> {
    let address = Address::decode(&decode(hash.into_inner()).map_err(ErrorInternalServerError)?)
        .map_err(ErrorInternalServerError)?;
    if let Address::Hash(hash) = address {
        let connection = state.db_pool.get().map_err(ErrorInternalServerError)?;
        let response = retrieve_file(&connection, hash);

        debug!("{:?}", response);

        match response {
            Ok(result) => match result {
                Some(path) => Ok(NamedFile::open(state.directory.join(path))?),
                None => Err(error::ErrorNotFound("NOT FOUND")),
            },
            Err(e) => Err(error::ErrorInternalServerError(e)),
        }
    } else {
        Err(ErrorBadRequest("Address does not refer to a file."))
    }
}

#[get("/api/obj/{address_str}")]
pub async fn get_object(
    state: web::Data<State>,
    address_str: web::Path<String>,
) -> Result<HttpResponse, Error> {
    let connection = state.db_pool.get().map_err(ErrorInternalServerError)?;
    let response: Result<Vec<Entry>> = retrieve_object(
        &connection,
        Address::decode(&decode(address_str.into_inner()).map_err(ErrorBadRequest)?)
            .map_err(ErrorInternalServerError)?,
    );

    debug!("{:?}", response);

    let mut result: HashMap<String, Entry> = HashMap::new();
    for entry in response.map_err(error::ErrorInternalServerError)? {
        result.insert(
            encode(entry.hash().map_err(ErrorInternalServerError)?),
            entry,
        );
    }
    Ok(HttpResponse::Ok().json(result))
}

const MAX_SIZE: usize = 1_000_000;

#[put("/api/obj")]
pub async fn put_object(
    state: web::Data<State>,
    mut payload: web::Payload,
) -> Result<HttpResponse, Error> {
    let connection = state.db_pool.get().map_err(ErrorInternalServerError)?;

    let mut body = web::BytesMut::new();
    while let Some(chunk) = payload.next().await {
        let chunk = chunk?;
        // limit max size of in-memory payload
        if (body.len() + chunk.len()) > MAX_SIZE {
            return Err(error::ErrorBadRequest("overflow."));
        }
        body.extend_from_slice(&chunk);
    }

    let entry = serde_json::from_slice::<Entry>(&body)?;

    let result_address = insert_entry(&connection, entry).map_err(ErrorInternalServerError)?;

    Ok(HttpResponse::Ok().json(result_address))
}

#[delete("/api/obj/{address_str}")]
pub async fn delete_object(
    state: web::Data<State>,
    address_str: web::Path<String>,
) -> Result<HttpResponse, Error> {
    let connection = state.db_pool.get().map_err(ErrorInternalServerError)?;
    let _ = remove_object(
        &connection,
        Address::decode(&decode(address_str.into_inner()).map_err(ErrorBadRequest)?)
            .map_err(ErrorInternalServerError)?,
    )
    .map_err(ErrorInternalServerError)?;

    Ok(HttpResponse::Ok().finish())
}

#[get("/api/hier/{path:.*}")]
pub async fn list_hier(
    state: web::Data<State>,
    path: web::Path<String>,
) -> Result<HttpResponse, Error> {
    let connection = state.db_pool.get().map_err(ErrorInternalServerError)?;
    let upath: UPath = path.into_inner().parse().map_err(ErrorBadRequest)?;
    let entries: Vec<Entry> = list_directory(&connection, &upath)
        .await
        .map_err(ErrorNotFound)?; // todo: 500 if actual error occurs

    Ok(HttpResponse::Ok().json(entries))
}

#[derive(Deserialize)]
pub struct LookupRequest {
    query: String,
}

#[get("/api/lookup")]
pub async fn get_lookup(
    state: web::Data<State>,
    web::Query(info): web::Query<LookupRequest>,
) -> Result<HttpResponse, Error> {
    let connection = state.db_pool.get().map_err(ErrorInternalServerError)?;
    let response = lookup_by_filename(&connection, info.query).map_err(ErrorInternalServerError)?;

    Ok(HttpResponse::Ok().json(response))
}

#[derive(Deserialize)]
pub struct QueryRequest {
    query: String,
}

#[get("/api/query")]
pub async fn get_query(
    state: web::Data<State>,
    web::Query(info): web::Query<QueryRequest>,
) -> Result<HttpResponse, Error> {
    let connection = state.db_pool.get().map_err(ErrorInternalServerError)?;

    let sexp = lexpr::from_str(info.query.as_str()).map_err(ErrorInternalServerError)?;
    let in_query = Query::from_sexp(&sexp).map_err(ErrorInternalServerError)?;
    let result = query(&connection, in_query).map_err(ErrorInternalServerError)?;

    Ok(HttpResponse::Ok().json(result))
}

#[post("/api/refresh")]
pub async fn api_refresh(state: web::Data<State>) -> Result<HttpResponse, Error> {
    let _pool = state.db_pool.clone();
    let _directory = state.directory.clone();
    actix::spawn(crate::filesystem::reimport_directory(_pool, _directory));
    Ok(HttpResponse::Ok().finish())
}