package buildstep

import (
	"encoding/json"
	"sync"
	"testing"

	stdio "git.novox.be/novox/mesh-sdk/go"
)

// configWatch is a double of stdio.WatchConfig: it hands the value now at the start, as the runtime does, and a test
// hands each change after with set.
type configWatch struct {
	mu     sync.Mutex
	value  string
	handle func(stdio.ProvisionChange) error
	asked  string
}

func (w *configWatch) watch(key string, handle func(stdio.ProvisionChange) error) error {
	w.mu.Lock()
	w.asked, w.handle = key, handle
	value := w.value
	w.mu.Unlock()
	return handle(stdio.ProvisionChange{Kind: "config", Key: key, Value: json.RawMessage(`"` + value + `"`)})
}

func (w *configWatch) set(t *testing.T, value string) {
	t.Helper()
	w.mu.Lock()
	handle, key := w.handle, w.asked
	w.mu.Unlock()
	if handle == nil {
		t.Fatal("the puller watches no config value")
	}
	if err := handle(stdio.ProvisionChange{Kind: "config", Key: key, Value: json.RawMessage(`"` + value + `"`)}); err != nil {
		t.Fatal(err)
	}
}