Wire plan_ready, list_ready, new_suggestions and Send to Google Chat (Feature 19) (#167)

Co-authored-by: orchestrator-agent <20+orchestrator-agent@code.cubecraftcreations.com>

internal/chat/chattest/chattest.go

@@ -0,0 +1,97 @@
+// Package chattest provides a fake Google Chat incoming webhook for tests
+// of the features that post to Google Chat: an httptest server that
+// records each post and answers a status the test sets, reached through a
+// transport that sends chat.googleapis.com requests to it.
+package chattest
+
+import (
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"sync"
+	"testing"
+)
+
+// Webhook is a valid Google Chat incoming webhook URL to store.
+const Webhook = "https://chat.googleapis.com/v1/spaces/AAQA1b2C3d4/messages?key=AIzaSyDdI0hCZtE6vySjMm-WEfRq3CPzqKqqsHI&token=q0Lz3kV9Yw8pXcRtN2bHsJdFgA7uEmKiOlP1nZxQ%3D"
+
+// Post is one message the fake received.
+type Post struct {
+	// Query is the request's query: key, token and any threading.
+	Query url.Values
+	// Body is the decoded JSON message.
+	Body map[string]any
+}
+
+// Text is the post's text.
+func (p Post) Text() string {
+	s, _ := p.Body["text"].(string)
+	return s
+}
+
+// Chat is a fake Google Chat endpoint. It answers 200 until SetStatus.
+type Chat struct {
+	srv    *httptest.Server
+	mu     sync.Mutex
+	status int
+	posts  []Post
+}
+
+// New starts a fake Google Chat endpoint, closed when the test ends.
+func New(t *testing.T) *Chat {
+	t.Helper()
+	c := &Chat{status: http.StatusOK}
+	c.srv = httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		data, _ := io.ReadAll(r.Body)
+		var body map[string]any
+		if err := json.Unmarshal(data, &body); err != nil {
+			t.Errorf("Google Chat post body %q: %v", data, err)
+		}
+		c.mu.Lock()
+		c.posts = append(c.posts, Post{Query: r.URL.Query(), Body: body})
+		status := c.status
+		c.mu.Unlock()
+		w.WriteHeader(status)
+	}))
+	t.Cleanup(c.srv.Close)
+	return c
+}
+
+// Transport sends every request to the fake, as if it were
+// chat.googleapis.com.
+func (c *Chat) Transport() http.RoundTripper {
+	return transport{c}
+}
+
+type transport struct{ c *Chat }
+
+func (tr transport) RoundTrip(req *http.Request) (*http.Response, error) {
+	target, err := url.Parse(tr.c.srv.URL)
+	if err != nil {
+		return nil, err
+	}
+	out := req.Clone(req.Context())
+	out.URL.Scheme, out.URL.Host = target.Scheme, target.Host
+	return http.DefaultTransport.RoundTrip(out)
+}
+
+// SetStatus makes the fake answer status from now on.
+func (c *Chat) SetStatus(status int) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.status = status
+}
+
+// Close stops the fake, so posts get no answer.
+func (c *Chat) Close() {
+	c.srv.Close()
+}
+
+// Posts returns the messages received so far, in order.
+func (c *Chat) Posts() []Post {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	return append([]Post(nil), c.posts...)
+}