Haystack/backend/events.go

package main

import (
	"context"
	"database/sql"
	"encoding/json"
	"fmt"
	"net/http"
	"os"
	"screenmark/screenmark/agents"
	"screenmark/screenmark/models"
	"time"

	"github.com/charmbracelet/log"
	"github.com/google/uuid"
	"github.com/lib/pq"
)

type Notification struct {
	ImageID uuid.UUID
	Status  string
}

func ListenNewImageEvents(db *sql.DB, notifier *Notifier[Notification]) {
	listener := pq.NewListener(os.Getenv("DB_CONNECTION"), time.Second, time.Second, func(event pq.ListenerEventType, err error) {
		if err != nil {
			panic(err)
		}
	})
	defer listener.Close()

	locationModel := models.NewLocationModel(db)
	eventModel := models.NewEventModel(db)
	noteModel := models.NewNoteModel(db)
	imageModel := models.NewImageModel(db)
	contactModel := models.NewContactModel(db)

	databaseEventLog := createLogger("Database Events 🤖", os.Stdout)
	databaseEventLog.SetLevel(log.DebugLevel)

	err := listener.Listen("new_image")
	if err != nil {
		panic(err)
	}

	for {
		select {
		case parameters := <-listener.Notify:
			imageId := uuid.MustParse(parameters.Extra)

			databaseEventLog.Debug("Starting processing image", "ImageID", imageId)

			ctx := context.Background()

			go func() {
				image, err := imageModel.GetToProcessWithData(ctx, imageId)
				if err != nil {
					databaseEventLog.Error("Failed to GetToProcessWithData", "error", err)
					return
				}

				splitWriter := createDbStdoutWriter(db, image.ImageID)

				noteAgent := agents.NewNoteAgent(createLogger("Notes 📝", splitWriter), noteModel)
				contactAgent := agents.NewContactAgent(createLogger("Contacts 👥", splitWriter), contactModel)
				locationAgent := agents.NewLocationAgent(createLogger("Locations 📍", splitWriter), locationModel)
				eventAgent := agents.NewEventAgent(createLogger("Events 📅", splitWriter), eventModel, locationModel)

				if err := imageModel.StartProcessing(ctx, image.ID); err != nil {
					databaseEventLog.Error("Failed to FinishProcessing", "error", err)
					return
				}

				orchestrator := agents.NewOrchestratorAgent(createLogger("Orchestrator 🎼", splitWriter), noteAgent, contactAgent, locationAgent, eventAgent, image.Image.ImageName, image.Image.Image)
				orchestrator.RunAgent(image.UserID, image.ImageID, image.Image.ImageName, image.Image.Image)
				_, err = imageModel.FinishProcessing(ctx, image.ID)
				if err != nil {
					databaseEventLog.Error("Failed to finish processing", "ImageID", imageId, "error", err)
					return
				}

				databaseEventLog.Debug("Finished processing image", "ImageID", imageId)
			}()
		}
	}
}

func ListenProcessingImageStatus(db *sql.DB, images models.ImageModel, notifier *Notifier[Notification]) {
	listener := pq.NewListener(os.Getenv("DB_CONNECTION"), time.Second, time.Second, func(event pq.ListenerEventType, err error) {
		if err != nil {
			panic(err)
		}
	})
	defer listener.Close()

	logger := createLogger("Image Status 📊", os.Stdout)

	if err := listener.Listen("new_processing_image_status"); err != nil {
		panic(err)
	}

	for {
		select {
		case data := <-listener.Notify:
			imageStringUuid := data.Extra[0:36]
			status := data.Extra[36:]

			imageUuid, err := uuid.Parse(imageStringUuid)
			if err != nil {
				logger.Error(err)
				continue
			}

			processingImage, err := images.GetToProcess(context.Background(), imageUuid)
			if err != nil {
				logger.Error("GetToProcess failed", "err", err)
				continue
			}

			logger.Info("Update", "id", imageStringUuid, "status", status)

			notification := Notification{
				ImageID: processingImage.ImageID,
				Status:  status,
			}

			if err := notifier.SendAndCreate(processingImage.UserID.String(), notification); err != nil {
				logger.Error(err)
			}
		}
	}
}

func CreateEventsHandler(notifier *Notifier[Notification]) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		userId := r.Context().Value(USER_ID).(uuid.UUID)
		if userId == uuid.Nil {
			w.WriteHeader(http.StatusUnauthorized)
			return
		}

		w.Header().Set("Content-Type", "text/event-stream")
		w.Header().Set("Cache-Control", "no-cache")
		w.Header().Set("Connection", "keep-alive")
		// w.(http.Flusher).Flush()

		// if err := notifier.Create(userId.String()); err != nil {
		// 	// TODO: this could be better.
		// 	// EG: The user could attempt to create many connections
		// 	// and they just get a 500, with no explanation.
		// 	fmt.Println(err)
		// 	w.WriteHeader(http.StatusInternalServerError)
		// 	// w.(http.Flusher).Flush()
		// 	return
		// }

		listener := notifier.Listeners[userId.String()]

		for {
			select {
			case <-r.Context().Done():
				fmt.Fprint(w, "event: close\ndata: Connection closed\n\n")
				w.(http.Flusher).Flush()
				return
			case msg := <-listener:

				msgString, err := json.Marshal(msg)
				if err != nil {
					w.WriteHeader(http.StatusInternalServerError)
					return
				}

				fmt.Printf("Sending msg %s\n", msg)
				fmt.Fprintf(w, "event: data\ndata: %s\n\n", string(msgString))
				w.(http.Flusher).Flush()
			}
		}
	}
}