// Copyright (C) 2021 Storj Labs, Inc.
// See LICENSE for copying information.

package consoleapi

import (
	"encoding/json"
	"io/ioutil"
	"net/http"

	"github.com/zeebo/errs"
	"go.uber.org/zap"

	"storj.io/storj/satellite/analytics"
	"storj.io/storj/satellite/console"
)

var (
	// ErrAnalyticsAPI - console analytics api error type.
	ErrAnalyticsAPI = errs.Class("console analytics api error")
)

// Analytics is an api controller that exposes analytics related functionality.
type Analytics struct {
	log       *zap.Logger
	service   *console.Service
	analytics *analytics.Service
}

// NewAnalytics is a constructor for api analytics controller.
func NewAnalytics(log *zap.Logger, service *console.Service, a *analytics.Service) *Analytics {
	return &Analytics{
		log:       log,
		service:   service,
		analytics: a,
	}
}

type eventTriggeredBody struct {
	EventName string `json:"eventName"`
}

// EventTriggered tracks the occurrence of an arbitrary event on the client.
func (a *Analytics) EventTriggered(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()
	var err error
	defer mon.Task()(&ctx)(&err)

	body, err := ioutil.ReadAll(r.Body)
	if err != nil {
		a.serveJSONError(w, http.StatusInternalServerError, err)
	}
	var et eventTriggeredBody
	err = json.Unmarshal(body, &et)
	if err != nil {
		a.serveJSONError(w, http.StatusInternalServerError, err)
	}
	userID, err := a.service.GetUserID(ctx)
	if err != nil {
		a.serveJSONError(w, http.StatusInternalServerError, err)
		return
	}

	a.analytics.TrackEvent(et.EventName, userID)
	w.WriteHeader(http.StatusOK)
}

// serveJSONError writes JSON error to response output stream.
func (a *Analytics) serveJSONError(w http.ResponseWriter, status int, err error) {
	w.WriteHeader(status)

	if status == http.StatusNoContent {
		return
	}

	if status == http.StatusInternalServerError {
		a.log.Error("returning internal server error to client", zap.Int("code", status), zap.Error(err))
	} else {
		a.log.Debug("returning error to client", zap.Int("code", status), zap.Error(err))
	}

	var response struct {
		Error string `json:"error"`
	}

	response.Error = err.Error()

	err = json.NewEncoder(w).Encode(response)
	if err != nil {
		a.log.Error("failed to write json error response", zap.Error(ErrAPIKeysAPI.Wrap(err)))
	}
}