use actix_web::web::Payload;
use actix_web::{delete, get, post, put};
use actix_web::{web, HttpResponse};
use indexmap::IndexMap;
use log::error;
use milli::update::{IndexDocumentsMethod, UpdateFormat};
use serde::Deserialize;
use serde_json::Value;

use crate::error::ResponseError;
use crate::helpers::Authentication;
use crate::routes::IndexParam;
use crate::Data;

const DEFAULT_RETRIEVE_DOCUMENTS_OFFSET: usize = 0;
const DEFAULT_RETRIEVE_DOCUMENTS_LIMIT: usize = 20;

macro_rules! guard_content_type {
    ($fn_name:ident, $guard_value:literal) => {
        #[allow(dead_code)]
        fn $fn_name(head: &actix_web::dev::RequestHead) -> bool {
            if let Some(content_type) = head.headers.get("Content-Type") {
                content_type
                    .to_str()
                    .map(|v| v.contains($guard_value))
                    .unwrap_or(false)
            } else {
                false
            }
        }
    };
}

guard_content_type!(guard_json, "application/json");

type Document = IndexMap<String, Value>;

#[derive(Deserialize)]
struct DocumentParam {
    index_uid: String,
    document_id: String,
}

pub fn services(cfg: &mut web::ServiceConfig) {
    cfg.service(get_document)
        .service(delete_document)
        .service(get_all_documents)
        .service(add_documents)
        .service(update_documents)
        .service(delete_documents)
        .service(clear_all_documents);
}

#[get(
    "/indexes/{index_uid}/documents/{document_id}",
    wrap = "Authentication::Public"
)]
async fn get_document(
    data: web::Data<Data>,
    path: web::Path<DocumentParam>,
) -> Result<HttpResponse, ResponseError> {
    let index = path.index_uid.clone();
    let id = path.document_id.clone();
    match data
        .retrieve_document(index, id, None as Option<Vec<String>>)
        .await
    {
        Ok(document) => Ok(HttpResponse::Ok().json(document)),
        Err(e) => {
            Ok(HttpResponse::BadRequest().json(serde_json::json!({ "error": e.to_string() })))
        }
    }
}

#[delete(
    "/indexes/{index_uid}/documents/{document_id}",
    wrap = "Authentication::Private"
)]
async fn delete_document(
    data: web::Data<Data>,
    path: web::Path<DocumentParam>,
) -> Result<HttpResponse, ResponseError> {
    match data
        .delete_documents(path.index_uid.clone(), vec![path.document_id.clone()])
        .await
    {
        Ok(update_status) => Ok(
            HttpResponse::Accepted().json(serde_json::json!({ "updateId": update_status.id() }))
        ),
        Err(e) => {
            Ok(HttpResponse::BadRequest().json(serde_json::json!({ "error": e.to_string() })))
        }
    }
}

#[derive(Deserialize)]
#[serde(rename_all = "camelCase", deny_unknown_fields)]
struct BrowseQuery {
    offset: Option<usize>,
    limit: Option<usize>,
    attributes_to_retrieve: Option<String>,
}

#[get("/indexes/{index_uid}/documents", wrap = "Authentication::Public")]
async fn get_all_documents(
    data: web::Data<Data>,
    path: web::Path<IndexParam>,
    params: web::Query<BrowseQuery>,
) -> Result<HttpResponse, ResponseError> {
    let attributes_to_retrieve = params
    .attributes_to_retrieve
    .as_ref()
    .and_then(|attrs| {
        let mut names = Vec::new();
        for name in attrs.split(',').map(String::from) {
            if name == "*" {
                return None
            }
            names.push(name);
        }
        Some(names)
    });

    match data
        .retrieve_documents(
            path.index_uid.clone(),
            params.offset.unwrap_or(DEFAULT_RETRIEVE_DOCUMENTS_OFFSET),
            params.limit.unwrap_or(DEFAULT_RETRIEVE_DOCUMENTS_LIMIT),
            attributes_to_retrieve,
        )
        .await
    {
        Ok(documents) => Ok(HttpResponse::Ok().json(documents)),
        Err(e) => {
            Ok(HttpResponse::BadRequest().json(serde_json::json!({ "error": e.to_string() })))
        }
    }
}

#[derive(Deserialize)]
#[serde(rename_all = "camelCase", deny_unknown_fields)]
struct UpdateDocumentsQuery {
    primary_key: Option<String>,
}

/// Route used when the payload type is "application/json"
/// Used to add or replace documents
#[post("/indexes/{index_uid}/documents", wrap = "Authentication::Private")]
async fn add_documents(
    data: web::Data<Data>,
    path: web::Path<IndexParam>,
    params: web::Query<UpdateDocumentsQuery>,
    body: Payload,
) -> Result<HttpResponse, ResponseError> {
    let addition_result = data
        .add_documents(
            path.into_inner().index_uid,
            IndexDocumentsMethod::ReplaceDocuments,
            UpdateFormat::Json,
            body,
            params.primary_key.clone(),
        )
        .await;

    match addition_result {
        Ok(update_status) => Ok(
            HttpResponse::Accepted().json(serde_json::json!({ "updateId": update_status.id() }))
        ),
        Err(e) => {
            Ok(HttpResponse::BadRequest().json(serde_json::json!({ "error": e.to_string() })))
        }
    }
}

/// Default route for adding documents, this should return an error and redirect to the documentation
#[post("/indexes/{index_uid}/documents", wrap = "Authentication::Private")]
async fn add_documents_default(
    _data: web::Data<Data>,
    _path: web::Path<IndexParam>,
    _params: web::Query<UpdateDocumentsQuery>,
    _body: web::Json<Vec<Document>>,
) -> Result<HttpResponse, ResponseError> {
    error!("Unknown document type");
    todo!()
}

/// Default route for adding documents, this should return an error and redirect to the documentation
#[put("/indexes/{index_uid}/documents", wrap = "Authentication::Private")]
async fn update_documents_default(
    _data: web::Data<Data>,
    _path: web::Path<IndexParam>,
    _params: web::Query<UpdateDocumentsQuery>,
    _body: web::Json<Vec<Document>>,
) -> Result<HttpResponse, ResponseError> {
    error!("Unknown document type");
    todo!()
}

#[put("/indexes/{index_uid}/documents", wrap = "Authentication::Private")]
async fn update_documents(
    data: web::Data<Data>,
    path: web::Path<IndexParam>,
    params: web::Query<UpdateDocumentsQuery>,
    body: web::Payload,
) -> Result<HttpResponse, ResponseError> {
    let addition_result = data
        .add_documents(
            path.into_inner().index_uid,
            IndexDocumentsMethod::UpdateDocuments,
            UpdateFormat::Json,
            body,
            params.primary_key.clone(),
        )
        .await;

    match addition_result {
        Ok(update) => {
            Ok(HttpResponse::Accepted().json(serde_json::json!({ "updateId": update.id() })))
        }
        Err(e) => {
            Ok(HttpResponse::BadRequest().json(serde_json::json!({ "error": e.to_string() })))
        }
    }
}

#[post(
    "/indexes/{index_uid}/documents/delete-batch",
    wrap = "Authentication::Private"
)]
async fn delete_documents(
    data: web::Data<Data>,
    path: web::Path<IndexParam>,
    body: web::Json<Vec<Value>>,
) -> Result<HttpResponse, ResponseError> {
    let ids = body
        .iter()
        .map(|v| {
            v.as_str()
                .map(String::from)
                .unwrap_or_else(|| v.to_string())
        })
        .collect();

    match data.delete_documents(path.index_uid.clone(), ids).await {
        Ok(update_status) => Ok(
            HttpResponse::Accepted().json(serde_json::json!({ "updateId": update_status.id() }))
        ),
        Err(e) => {
            Ok(HttpResponse::BadRequest().json(serde_json::json!({ "error": e.to_string() })))
        }
    }
}

/// delete all documents
#[delete("/indexes/{index_uid}/documents", wrap = "Authentication::Private")]
async fn clear_all_documents(
    data: web::Data<Data>,
    path: web::Path<IndexParam>,
) -> Result<HttpResponse, ResponseError> {
    match data.clear_documents(path.index_uid.clone()).await {
        Ok(update_status) => Ok(
            HttpResponse::Accepted().json(serde_json::json!({ "updateId": update_status.id() }))
        ),
        Err(e) => {
            Ok(HttpResponse::BadRequest().json(serde_json::json!({ "error": e.to_string() })))
        }
    }
}