package analyticsApi

import (
	"git.stuve.uni-ulm.de/stuve-it/stuve-it-backend/ldapApi"
	"git.stuve.uni-ulm.de/stuve-it/stuve-it-backend/logger"
	"github.com/labstack/echo/v5"
	"github.com/pocketbase/dbx"
	"github.com/pocketbase/pocketbase"
	"github.com/pocketbase/pocketbase/apis"
	"github.com/pocketbase/pocketbase/core"
	"time"
)

// initSessionCount
//
// this endpoint is used to aggregate session metadata counts
// it adds the following endpoint to the app:
// GET /api/analytics/sessionCounts
//
// the endpoint expects the following request data:
//
//	{
//	  "startDate": "start date in ISO 8601 format",
//	}
func initSessionCount(app *pocketbase.PocketBase, e *core.ServeEvent) {
	e.Router.GET("/api/analytics/sessionCounts", func(c echo.Context) error {

		// Check if user is in admin group
		if err := ldapApi.UserIsInAdminGroup(app, c); err != nil {
			return err
		}

		// Get data from request
		data := struct {
			StartDate string `json:"startDate"`
		}{}
		if err := c.Bind(&data); err != nil {
			return apis.NewBadRequestError("Failed to read request data", err)
		}

		// Parse the start date
		startDate, err := time.Parse(time.RFC3339, data.StartDate)
		if err != nil {
			return apis.NewBadRequestError("Invalid start date format, expected ISO 8601", err)
		}

		type Data struct {
			Value string `db:"value" json:"value"`
			Count int    `db:"count" json:"count"`
		}

		// Use a map to store the response data
		response := make(map[string][]Data)

		fields := []string{"device_type", "browser_name", "operating_system", "user_agent", "geo_country_code", "preferred_language"}

		for _, field := range fields {
			data := []Data{}

			err := app.Dao().DB().
				NewQuery(`
					SELECT ` + field + ` as value, COUNT(id) AS count
					FROM analyticsPageViews
					WHERE created >= {:startDate}
					GROUP BY ` + field).
				Bind(dbx.Params{
					"startDate": startDate,
				}).
				All(&data)

			if err != nil {
				return apis.NewApiError(500, "Failed to aggregate data for "+field, err)
			}

			// Assign the data to the corresponding field in the map
			response[field] = data
		}

		// Return the final JSON response
		return c.JSON(200, response)
	}, apis.ActivityLogger(app))

}

// InitAnalyticsApi initializes analytics api endpoints
func InitAnalyticsApi(app *pocketbase.PocketBase, e *core.ServeEvent) error {

	logger.LogInfoF("Initializing analytics api")

	initSessionCount(app, e)

	return nil
}