// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
// SPDX-License-Identifier: MIT

//go:build linux || freebsd

package telegram

import (
	"encoding/json"
	"io"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"
	"time"

	"sourcedock.dev/petrbalvin/nuntius/internal/contactform"
)

var testRequest = contactform.Request{
	Name:    "Jane Doe",
	Email:   "jane@example.com",
	Service: "architecture",
	Message: "Hello, I would like to discuss an engagement.",
}

// apiCall carries what the fake API saw; the channel establishes the
// happens-before edge the HTTP response alone does not.
type apiCall struct {
	req  *http.Request
	body string
}

// fakeAPI answers with the given payload and records the request; the
// returned function waits for the call and yields it.
func fakeAPI(t *testing.T, status int, payload string) (*Notifier, func() apiCall) {
	t.Helper()
	calls := make(chan apiCall, 1)
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		b, _ := io.ReadAll(r.Body)
		calls <- apiCall{req: r, body: string(b)}
		w.WriteHeader(status)
		_, _ = w.Write([]byte(payload))
	}))
	t.Cleanup(srv.Close)

	n := New("123:secret", "-100200300", 5*time.Second)
	n.apiURL = srv.URL
	return n, func() apiCall {
		select {
		case c := <-calls:
			return c
		case <-time.After(5 * time.Second):
			t.Fatal("the fake API never saw the request")
			return apiCall{}
		}
	}
}

func TestNotifyPostsTheSummary(t *testing.T) {
	n, call := fakeAPI(t, http.StatusOK, `{"ok":true}`)

	if err := n.Notify("contact", testRequest); err != nil {
		t.Fatalf("notify: %v", err)
	}
	got := call()
	if p := got.req.URL.Path; p != "/bot123:secret/sendMessage" {
		t.Errorf("path = %q, want the bot token and sendMessage", p)
	}
	var payload struct {
		ChatID string `json:"chat_id"`
		Text   string `json:"text"`
	}
	if err := json.Unmarshal([]byte(got.body), &payload); err != nil {
		t.Fatalf("decode payload: %v", err)
	}
	if payload.ChatID != "-100200300" {
		t.Errorf("chat_id = %q, want the configured chat", payload.ChatID)
	}
	for _, want := range []string{
		"New message on contact",
		"From: Jane Doe <jane@example.com>",
		"Service interest: architecture",
		"Hello, I would like to discuss an engagement.",
	} {
		if !strings.Contains(payload.Text, want) {
			t.Errorf("summary missing %q", want)
		}
	}
}

func TestNotifyReportsAPIRefusal(t *testing.T) {
	// The API refuses with a non-200 status and an ok:false body; both
	// shapes must surface as an error.
	n, _ := fakeAPI(t, http.StatusUnauthorized, `{"ok":false,"description":"Unauthorized"}`)
	if err := n.Notify("contact", testRequest); err == nil {
		t.Errorf("notify over HTTP 401 succeeded, want an error")
	}

	n, _ = fakeAPI(t, http.StatusOK, `{"ok":false,"description":"chat not found"}`)
	if err := n.Notify("contact", testRequest); err == nil {
		t.Errorf("notify over an ok:false body succeeded, want an error")
	}
}

// TestNotifyRedactsTheToken pins the credential rule: the token never
// reaches an error string, and error text is what the log carries.
func TestNotifyRedactsTheToken(t *testing.T) {
	var srv *httptest.Server
	srv = httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		// A connection reset surfaces as an URL error carrying the full
		// request URL, token included.
		srv.CloseClientConnections()
	}))
	t.Cleanup(srv.Close)

	n := New("123:secret", "-100200300", 5*time.Second)
	n.apiURL = srv.URL

	err := n.Notify("contact", testRequest)
	if err == nil {
		t.Fatalf("notify over a killed connection succeeded, want an error")
	}
	if strings.Contains(err.Error(), "123:secret") {
		t.Errorf("error text carries the bot token: %q", err.Error())
	}
}