state_ready.go

package gateway

import (
	"errors"
	"fmt"
	"github.com/discordpkg/gateway/encoding"
	"io"

	"github.com/discordpkg/gateway/event/opcode"
)

type Ready struct {
	SessionID        string `json:"session_id"`
	ResumeGatewayURL string `json:"resume_gateway_url"`
}

// ReadyState is responsibile for the Ready phase of the gateway connection. It's responsibilities are:
//  1. Process incoming Ready event
//  2. Cache relevant Discord session data
//  4. Transition to the ConnectedState
//
// See the Discord documentation for more information:
//   - https://discord.com/developers/docs/topics/gateway#ready-event
type ReadyState struct {
	ctx *StateCtx
}

func (st *ReadyState) String() string {
	return "ready"
}

func (st *ReadyState) Process(payload *Payload, _ io.Writer) error {
	if payload.Op != opcode.Dispatch {
		st.ctx.SetState(&ClosedState{})
		return errors.New(fmt.Sprintf("incorrect opcode: %d, wants %d", int(payload.Op), int(opcode.Dispatch)))
	}

	var ready Ready
	if err := encoding.Unmarshal(payload.Data, &ready); err != nil {
		st.ctx.SetState(&ClosedState{})
		return err
	}

	st.ctx.SessionID = ready.SessionID
	st.ctx.ResumeGatewayURL = ready.ResumeGatewayURL

	st.ctx.SetState(&ConnectedState{ctx: st.ctx})
	return nil
}