package api

import (
	"bytes"
	"context"
	"errors"
	"net/http"
	"net/http/httptest"
	"os"
	"strings"
	"testing"

	"github.com/jackc/pgx/v5/pgxpool"

	"git.fabledsword.com/bvandeusen/minstrel/internal/mailer"
	"git.fabledsword.com/bvandeusen/minstrel/internal/netsettings"
)

// withPublicURL gives h a network-settings service holding url, restoring an
// empty value afterwards so other tests see the default.
func withPublicURL(t *testing.T, h *handlers, pool *pgxpool.Pool, url string) {
	t.Helper()
	ns, err := netsettings.New(context.Background(), pool, nil)
	if err != nil {
		t.Fatalf("netsettings: %v", err)
	}
	if err := ns.SetPublicURL(context.Background(), url); err != nil {
		t.Fatalf("set public url: %v", err)
	}
	t.Cleanup(func() { _ = ns.SetPublicURL(context.Background(), "") })
	h.netSettings = ns
}

// With no public URL set, a reset email is not sent at all, and the response
// is still the same opaque 200.
func TestForgotPassword_NoPublicURL_SendsNothing(t *testing.T) {
	if os.Getenv("MINSTREL_TEST_DATABASE_URL") == "" {
		t.Skip("MINSTREL_TEST_DATABASE_URL not set")
	}
	h, pool := testHandlers(t)
	fake := &mailer.FakeSender{}
	h.mailer = fake
	withPublicURL(t, h, pool, "")

	user := seedUser(t, pool, "nourl", "pw", false)
	if _, err := pool.Exec(context.Background(),
		"UPDATE users SET email = 'nourl@example.com' WHERE id = $1", user.ID); err != nil {
		t.Fatalf("seed email: %v", err)
	}
	req := httptest.NewRequest(http.MethodPost, "/api/auth/forgot-password",
		bytes.NewReader([]byte(`{"email":"nourl@example.com"}`)))
	rec := httptest.NewRecorder()
	h.handleForgotPassword(rec, req)

	if rec.Code != http.StatusOK {
		t.Errorf("status = %d, want 200", rec.Code)
	}
	if len(fake.Sent) != 0 {
		t.Errorf("sent %d emails with no public URL set, want 0", len(fake.Sent))
	}
}

func TestForgotPassword_KnownEmail_SendsMail(t *testing.T) {
	if os.Getenv("MINSTREL_TEST_DATABASE_URL") == "" {
		t.Skip("MINSTREL_TEST_DATABASE_URL not set")
	}
	h, pool := testHandlers(t)
	fake := &mailer.FakeSender{}
	h.mailer = fake
	withPublicURL(t, h, pool, "https://music.example.com")

	user := seedUser(t, pool, "forgotuser", "pw", false)
	if _, err := pool.Exec(context.Background(),
		"UPDATE users SET email = 'forgot@example.com' WHERE id = $1", user.ID); err != nil {
		t.Fatalf("seed email: %v", err)
	}

	body := `{"email":"forgot@example.com"}`
	req := httptest.NewRequest(http.MethodPost, "/api/auth/forgot-password",
		bytes.NewReader([]byte(body)))
	// A forged Host must not reach the link: it comes from the public URL.
	req.Host = "attacker.example.net"
	rec := httptest.NewRecorder()
	h.handleForgotPassword(rec, req)

	if rec.Code != http.StatusOK {
		t.Errorf("status = %d, want 200", rec.Code)
	}
	if len(fake.Sent) != 1 {
		t.Fatalf("Sent len = %d, want 1", len(fake.Sent))
	}
	got := fake.LastSent()
	if got.To != "forgot@example.com" {
		t.Errorf("To = %q, want forgot@example.com", got.To)
	}
	if !strings.Contains(got.TextBody, "https://music.example.com/reset-password/") {
		t.Errorf("reset link not built from the public URL:\n%s", got.TextBody)
	}
	if strings.Contains(got.TextBody+got.HTMLBody, "attacker.example.net") {
		t.Error("the request's Host header reached the emailed link")
	}
	// Token row was inserted.
	var tokenCount int
	if err := pool.QueryRow(context.Background(),
		"SELECT count(*) FROM password_resets WHERE user_id = $1", user.ID).Scan(&tokenCount); err != nil {
		t.Fatalf("verify token: %v", err)
	}
	if tokenCount == 0 {
		t.Errorf("no password_resets row inserted")
	}
}

func TestForgotPassword_UnknownEmail_Returns200_NoSend(t *testing.T) {
	if os.Getenv("MINSTREL_TEST_DATABASE_URL") == "" {
		t.Skip("MINSTREL_TEST_DATABASE_URL not set")
	}
	h, _ := testHandlers(t)
	fake := &mailer.FakeSender{}
	h.mailer = fake

	body := `{"email":"nonexistent@example.com"}`
	req := httptest.NewRequest(http.MethodPost, "/api/auth/forgot-password",
		bytes.NewReader([]byte(body)))
	rec := httptest.NewRecorder()
	h.handleForgotPassword(rec, req)

	if rec.Code != http.StatusOK {
		t.Errorf("status = %d, want 200 (always; no enumeration)", rec.Code)
	}
	if len(fake.Sent) != 0 {
		t.Errorf("Sent len = %d, want 0 for unknown email", len(fake.Sent))
	}
}

func TestForgotPassword_MailerFailure_StillReturns200(t *testing.T) {
	if os.Getenv("MINSTREL_TEST_DATABASE_URL") == "" {
		t.Skip("MINSTREL_TEST_DATABASE_URL not set")
	}
	h, pool := testHandlers(t)
	fake := &mailer.FakeSender{FailNext: errors.New("simulated SMTP failure")}
	h.mailer = fake

	user := seedUser(t, pool, "mailfail", "pw", false)
	if _, err := pool.Exec(context.Background(),
		"UPDATE users SET email = 'mailfail@example.com' WHERE id = $1", user.ID); err != nil {
		t.Fatalf("seed: %v", err)
	}

	body := `{"email":"mailfail@example.com"}`
	req := httptest.NewRequest(http.MethodPost, "/api/auth/forgot-password",
		bytes.NewReader([]byte(body)))
	rec := httptest.NewRecorder()
	h.handleForgotPassword(rec, req)

	if rec.Code != http.StatusOK {
		t.Errorf("status = %d, want 200 (mailer failures don't propagate)", rec.Code)
	}
}