eventbus for sending events from backend to frontend. stubbing out a block controller and blockservice

pkg/blockcontroller/blockcontroller.go

@@ -0,0 +1,95 @@
+// Copyright 2024, Command Line Inc.
+// SPDX-License-Identifier: Apache-2.0
+
+package blockcontroller
+
+import (
+	"encoding/json"
+	"fmt"
+	"sync"
+
+	"github.com/wailsapp/wails/v3/pkg/application"
+	"github.com/wavetermdev/thenextwave/pkg/eventbus"
+)
+
+var globalLock = &sync.Mutex{}
+var blockControllerMap = make(map[string]*BlockController)
+
+type BlockCommand interface {
+	GetType() string
+}
+
+type MessageCommand struct {
+	Message string `json:"message"`
+}
+
+func (mc *MessageCommand) GetType() string {
+	return "message"
+}
+
+type BlockController struct {
+	BlockId string
+	InputCh chan BlockCommand
+}
+
+func ParseCmdMap(cmdMap map[string]any) (BlockCommand, error) {
+	cmdType, ok := cmdMap["type"].(string)
+	if !ok {
+		return nil, fmt.Errorf("no type field in command map")
+	}
+	mapJson, err := json.Marshal(cmdMap)
+	if err != nil {
+		return nil, fmt.Errorf("error marshalling command map: %w", err)
+	}
+	switch cmdType {
+	case "message":
+		var cmd MessageCommand
+		err := json.Unmarshal(mapJson, &cmd)
+		if err != nil {
+			return nil, fmt.Errorf("error unmarshalling message command: %w", err)
+		}
+		return &cmd, nil
+	default:
+		return nil, fmt.Errorf("unknown command type %q", cmdType)
+	}
+}
+
+func (bc *BlockController) Run() {
+	defer func() {
+		eventbus.SendEvent(application.WailsEvent{
+			Name: "block:done",
+			Data: nil,
+		})
+		globalLock.Lock()
+		defer globalLock.Unlock()
+		delete(blockControllerMap, bc.BlockId)
+	}()
+
+	for genCmd := range bc.InputCh {
+		switch cmd := genCmd.(type) {
+		case *MessageCommand:
+			fmt.Printf("MESSAGE: %s | %q\n", bc.BlockId, cmd.Message)
+
+		default:
+			fmt.Printf("unknown command type %T\n", cmd)
+		}
+	}
+}
+
+func NewBlockController(blockId string) *BlockController {
+	globalLock.Lock()
+	defer globalLock.Unlock()
+	bc := &BlockController{
+		BlockId: blockId,
+		InputCh: make(chan BlockCommand),
+	}
+	blockControllerMap[blockId] = bc
+	go bc.Run()
+	return bc
+}
+
+func GetBlockController(blockId string) *BlockController {
+	globalLock.Lock()
+	defer globalLock.Unlock()
+	return blockControllerMap[blockId]
+}