package gonexapp

import (
	"encoding/json"
	"fmt"
	"net/http"
)

// Notification is one Nextcloud bell for a single Recipient.
type Notification struct {
	Subject       string
	Message       string
	Link          string
	SubjectParams map[string]any
	MessageParams map[string]any
}

// AppAPINotifications creates Notifications via AppAPI OCS.
type AppAPINotifications struct {
	Cred   Credentials
	Client *http.Client
	OCS    OCSClient
}

// NewAppAPINotifications returns a sender using cred for AppAPI auth.
func NewAppAPINotifications(cred Credentials) AppAPINotifications {
	return AppAPINotifications{
		Cred: cred,
		OCS:  OCSClient{Cred: cred},
	}
}

func (n AppAPINotifications) ocsClient() OCSClient {
	c := n.OCS
	if c.Cred.BaseURL == "" {
		c.Cred = n.Cred
	}
	if c.Client == nil {
		c.Client = n.Client
	}
	return c
}

// Send creates a Notification for the Requesting user on the Credentials.
func (n AppAPINotifications) Send(notif Notification) error {
	if n.Cred.UserID == "" {
		return fmt.Errorf("notification recipient user id is required")
	}
	return n.send(n.Cred.UserID, notif)
}

// SendTo creates a Notification for userID, impersonating that Recipient.
func (n AppAPINotifications) SendTo(userID string, notif Notification) error {
	return n.send(userID, notif)
}

func (n AppAPINotifications) send(userID string, notif Notification) error {
	if userID == "" {
		return fmt.Errorf("notification recipient user id is required")
	}
	if notif.Subject == "" {
		return fmt.Errorf("notification subject is required")
	}
	ocs := n.ocsClient()
	ocs.Cred = ocs.Cred.WithUser(userID)
	richSubjectParams := notif.SubjectParams
	if richSubjectParams == nil {
		richSubjectParams = map[string]any{}
	}
	subjectParams := map[string]any{
		"rich_subject":        notif.Subject,
		"rich_subject_params": richSubjectParams,
	}
	if notif.Message != "" {
		richMessageParams := notif.MessageParams
		if richMessageParams == nil {
			richMessageParams = map[string]any{}
		}
		subjectParams["rich_message"] = notif.Message
		subjectParams["rich_message_params"] = richMessageParams
	}
	if notif.Link != "" {
		subjectParams["link"] = notif.Link
	}
	body, _ := json.Marshal(map[string]any{
		"params": map[string]any{
			"object":         "app_api",
			"object_id":      "app_api_id",
			"subject_type":   "app_api_ex_app",
			"subject_params": subjectParams,
		},
	})
	_, err := ocs.Call(http.MethodPost, "apps/app_api/api/v1/notification", body)
	return err
}