package adminapi

import (
	"errors"
	"net/http"

	"github.com/dariuszjaniak/warp/server/internal/httputil"
	"github.com/dariuszjaniak/warp/server/internal/servernotices"
	"github.com/dariuszjaniak/warp/server/internal/userapi"
)

// serverNoticeRequest is the POST /server_notices body.
type serverNoticeRequest struct {
	UserID string `json:"user_id"`

	// Content is an m.room.message content. A body is required; a missing
	// msgtype becomes m.text.
	Content map[string]any `json:"content"`
}

// handlePostServerNotice implements POST /_warp/admin/v1/server_notices:
// send a message from the server to one of its users.
//
// The notice goes into the user's server notice room, which is made the
// first time and which the user is invited back to if they left it. The
// user does not have to be online or to accept anything first: the
// invite and the message wait for them.
func (a *AdminAPI) handlePostServerNotice(w http.ResponseWriter, r *http.Request, auth userapi.Authenticated) error {
	if a.notices == nil {
		return httputil.NewError(http.StatusConflict, httputil.ErrCodeForbidden,
			"Server notices are not configured (server_notices.enabled is false, or the server has no signing key)")
	}
	var req serverNoticeRequest
	if err := httputil.DecodeJSON(w, r, &req); err != nil {
		return err
	}
	if req.UserID == "" {
		return httputil.MissingParam("user_id is required")
	}
	if body, _ := req.Content["body"].(string); body == "" {
		return httputil.MissingParam("content.body is required")
	}
	localpart, err := a.users.ParseLocalUserID(req.UserID)
	if err != nil {
		return httputil.InvalidParam("%s is not a user of this server", req.UserID)
	}

	roomID, eventID, err := a.notices.Send(r.Context(), localpart, req.Content)
	switch {
	case errors.Is(err, servernotices.ErrNoSuchUser):
		return httputil.NotFound("No such user")
	case errors.Is(err, servernotices.ErrDeactivated):
		return httputil.Forbidden("%s is deactivated", req.UserID)
	case err != nil:
		return roomError(err)
	}
	a.audit(r.Context(), auth, auditServerNotice, a.users.UserID(localpart), map[string]any{
		"room_id": roomID, "event_id": eventID,
	})
	httputil.WriteJSON(w, http.StatusOK, map[string]string{"room_id": roomID, "event_id": eventID})
	return nil
}