use std::future::Future;
use std::sync::Arc;

use actix_web::http::header::ContentType;
use actix_web::http::StatusCode;
use actix_web::rt::time::Instant;
use actix_web::web::Query;
use actix_web::{get, post, web, HttpResponse, Responder};
use actix_web_validator::Json;
use collection::operations::verification::new_unchecked_verification_pass;
use common::types::{DetailsLevel, TelemetryDetail};
use schemars::JsonSchema;
use segment::common::anonymize::Anonymize;
use serde::{Deserialize, Serialize};
use storage::content_manager::errors::StorageError;
use storage::dispatcher::Dispatcher;
use storage::rbac::AccessRequirements;
use tokio::sync::Mutex;

use crate::actix::auth::ActixAccess;
use crate::actix::helpers::{self, process_response_error};
use crate::common::health;
use crate::common::helpers::LocksOption;
use crate::common::metrics::MetricsData;
use crate::common::stacktrace::get_stack_trace;
use crate::common::telemetry::TelemetryCollector;
use crate::tracing;

#[derive(Deserialize, Serialize, JsonSchema)]
pub struct TelemetryParam {
    pub anonymize: Option<bool>,
    pub details_level: Option<usize>,
}

#[get("/telemetry")]
fn telemetry(
    telemetry_collector: web::Data<Mutex<TelemetryCollector>>,
    params: Query<TelemetryParam>,
    ActixAccess(access): ActixAccess,
) -> impl Future<Output = HttpResponse> {
    helpers::time(async move {
        access.check_global_access(AccessRequirements::new())?;
        let anonymize = params.anonymize.unwrap_or(false);
        let details_level = params
            .details_level
            .map_or(DetailsLevel::Level0, Into::into);
        let detail = TelemetryDetail {
            level: details_level,
            histograms: false,
        };
        let telemetry_collector = telemetry_collector.lock().await;
        let telemetry_data = telemetry_collector.prepare_data(&access, detail).await;
        let telemetry_data = if anonymize {
            telemetry_data.anonymize()
        } else {
            telemetry_data
        };
        Ok(telemetry_data)
    })
}

#[derive(Deserialize, Serialize, JsonSchema)]
pub struct MetricsParam {
    pub anonymize: Option<bool>,
}

#[get("/metrics")]
async fn metrics(
    telemetry_collector: web::Data<Mutex<TelemetryCollector>>,
    params: Query<MetricsParam>,
    ActixAccess(access): ActixAccess,
) -> HttpResponse {
    if let Err(err) = access.check_global_access(AccessRequirements::new()) {
        return process_response_error(err, Instant::now(), None);
    }

    let anonymize = params.anonymize.unwrap_or(false);
    let telemetry_collector = telemetry_collector.lock().await;
    let telemetry_data = telemetry_collector
        .prepare_data(
            &access,
            TelemetryDetail {
                level: DetailsLevel::Level1,
                histograms: true,
            },
        )
        .await;
    let telemetry_data = if anonymize {
        telemetry_data.anonymize()
    } else {
        telemetry_data
    };

    HttpResponse::Ok()
        .content_type(ContentType::plaintext())
        .body(MetricsData::from(telemetry_data).format_metrics())
}

#[post("/locks")]
fn put_locks(
    dispatcher: web::Data<Dispatcher>,
    locks_option: Json<LocksOption>,
    ActixAccess(access): ActixAccess,
) -> impl Future<Output = HttpResponse> {
    // Not a collection level request.
    let pass = new_unchecked_verification_pass();

    helpers::time(async move {
        let toc = dispatcher.toc(&access, &pass);
        access.check_global_access(AccessRequirements::new().manage())?;
        let result = LocksOption {
            write: toc.is_write_locked(),
            error_message: toc.get_lock_error_message(),
        };
        toc.set_locks(locks_option.write, locks_option.error_message.clone());
        Ok(result)
    })
}

#[get("/locks")]
fn get_locks(
    dispatcher: web::Data<Dispatcher>,
    ActixAccess(access): ActixAccess,
) -> impl Future<Output = HttpResponse> {
    // Not a collection level request.
    let pass = new_unchecked_verification_pass();

    helpers::time(async move {
        access.check_global_access(AccessRequirements::new())?;
        let toc = dispatcher.toc(&access, &pass);
        let result = LocksOption {
            write: toc.is_write_locked(),
            error_message: toc.get_lock_error_message(),
        };
        Ok(result)
    })
}

#[get("/stacktrace")]
fn get_stacktrace(ActixAccess(access): ActixAccess) -> impl Future<Output = HttpResponse> {
    helpers::time(async move {
        access.check_global_access(AccessRequirements::new().manage())?;
        Ok(get_stack_trace())
    })
}

#[get("/healthz")]
async fn healthz() -> impl Responder {
    kubernetes_healthz()
}

#[get("/livez")]
async fn livez() -> impl Responder {
    kubernetes_healthz()
}

#[get("/readyz")]
async fn readyz(health_checker: web::Data<Option<Arc<health::HealthChecker>>>) -> impl Responder {
    let is_ready = match health_checker.as_ref() {
        Some(health_checker) => health_checker.check_ready().await,
        None => true,
    };

    let (status, body) = if is_ready {
        (StatusCode::OK, "all shards are ready")
    } else {
        (StatusCode::SERVICE_UNAVAILABLE, "some shards are not ready")
    };

    HttpResponse::build(status)
        .content_type(ContentType::plaintext())
        .body(body)
}

/// Basic Kubernetes healthz endpoint
fn kubernetes_healthz() -> impl Responder {
    HttpResponse::Ok()
        .content_type(ContentType::plaintext())
        .body("healthz check passed")
}

#[get("/logger")]
async fn get_logger_config(handle: web::Data<tracing::LoggerHandle>) -> impl Responder {
    let timing = Instant::now();
    let result = handle.get_config().await;
    helpers::process_response(Ok(result), timing, None)
}

#[post("/logger")]
async fn update_logger_config(
    handle: web::Data<tracing::LoggerHandle>,
    config: web::Json<tracing::LoggerConfig>,
) -> impl Responder {
    let timing = Instant::now();

    let result = handle
        .update_config(config.into_inner())
        .await
        .map(|_| true)
        .map_err(|err| StorageError::service_error(err.to_string()));

    helpers::process_response(result, timing, None)
}

// Configure services
pub fn config_service_api(cfg: &mut web::ServiceConfig) {
    cfg.service(telemetry)
        .service(metrics)
        .service(put_locks)
        .service(get_locks)
        .service(get_stacktrace)
        .service(healthz)
        .service(livez)
        .service(readyz)
        .service(get_logger_config)
        .service(update_logger_config);
}