package util

import (
	"fmt"

	"github.com/pocketbase/dbx"
	"github.com/pocketbase/pocketbase"
	"github.com/pocketbase/pocketbase/models"
)

type NotificationType string

const (
	TrailCreate  NotificationType = "trail_create"
	TrailShare   NotificationType = "trail_share"
	ListCreate   NotificationType = "list_create"
	ListShare    NotificationType = "list_share"
	NewFollower  NotificationType = "new_follower"
	TrailComment NotificationType = "trail_comment"
)

type Notification struct {
	Type     NotificationType `json:"type"`
	Metadata interface{}      `json:"metadata,omitempty"`
	Seen     bool             `json:"seen"`
	Author   string           `json:"author"`
}

type NotificationSettings struct {
	Web   bool `json:"web"`
	Email bool `json:"email"`
}

func getNotificationPermissions(app *pocketbase.PocketBase, user string, notificationType NotificationType) (*NotificationSettings, error) {
	settings, err := app.Dao().FindFirstRecordByFilter("settings", "user={:user}", dbx.Params{"user": user})
	if err != nil {
		return nil, err
	}
	var notificationPreferences map[NotificationType]NotificationSettings

	err = settings.UnmarshalJSONField("notifications", &notificationPreferences)
	if err != nil {
		return nil, err
	}

	settingsForType, exists := notificationPreferences[notificationType]
	if !exists {
		return nil, fmt.Errorf("notification type '%s' not found", notificationType)
	}

	return &settingsForType, nil
}

func SendNotification(app *pocketbase.PocketBase, notification Notification, recipient string) error {
	if notification.Author == recipient {
		return nil
	}
	permissions, err := getNotificationPermissions(app, recipient, notification.Type)
	if err != nil {
		return err
	}
	if !permissions.Web {
		return nil
	}
	notifications, err := app.Dao().FindCollectionByNameOrId("notifications")
	if err != nil {
		return err
	}
	n := models.NewRecord(notifications)
	n.Set("type", string(notification.Type))
	n.Set("metadata", notification.Metadata)
	n.Set("seen", notification.Seen)
	n.Set("recipient", recipient)
	n.Set("author", notification.Author)

	if err := app.Dao().SaveRecord(n); err != nil {
		return err
	}
	return nil
}

func SendNotificationToFollowers(app *pocketbase.PocketBase, notification Notification) error {
	followers, err := app.Dao().FindRecordsByFilter("follows", "followee={:user}", "", -1, 0, dbx.Params{"user": notification.Author})

	if err != nil {
		return err
	}
	notifications, err := app.Dao().FindCollectionByNameOrId("notifications")
	if err != nil {
		return err
	}
	for _, f := range followers {
		recipient := f.GetString("follower")
		if notification.Author == recipient {
			continue
		}
		permissions, err := getNotificationPermissions(app, recipient, notification.Type)
		if err != nil {
			continue
		}
		if !permissions.Web {
			continue
		}
		n := models.NewRecord(notifications)
		n.Set("type", string(notification.Type))
		n.Set("metadata", notification.Metadata)
		n.Set("seen", notification.Seen)
		n.Set("recipient", recipient)
		n.Set("author", notification.Author)

		if err := app.Dao().SaveRecord(n); err != nil {
			continue
		}
	}
	return nil
}