package weixin_ilink

import (
	"context"
	"errors"
	"net/http"
	"net/http/httptest"
	"testing"
	"time"

	"git.yeij.top/AskaEth/Cyrene_v2/internal/channel/adapter"
)

// 这些测试覆盖显式的「会话被拒绝」状态机（session_state.go）：iLink 回复
// errcode=-14 必须表现为「需要重新扫码」，而不是悄悄变哑的适配器、或一次拿着已被
// iLink 拒绝的凭据却上报成功的连接。

// rejectingServer 对每次 getupdates 长轮询都回以「会话被拒绝」错误码，正如 iLink
// 拒绝一份会话凭据那样。
func rejectingServer(t *testing.T) *httptest.Server {
	t.Helper()
	return newJSONServer(t, nil, func(req recordedReq) handlerResult {
		if req.path != "/ilink/bot/getupdates" {
			return handlerResult{status: 404}
		}
		return handlerResult{body: jsonBody(map[string]any{"errcode": errcodeSessionRejected})}
	})
}

// rejectByPoll 通过长轮询把适配器驱入被拒绝状态：ReadMessages 必须在 errcode=-14 时
// 返回，且适配器必须报告「需要重新扫码」状态。
func rejectByPoll(t *testing.T, ad *Adapter) {
	t.Helper()
	done := make(chan struct{})
	go func() {
		defer close(done)
		ad.ReadMessages(context.Background(), func(adapter.UnifiedMessage) {})
	}()
	waitDone(t, done)
	if required, reason := ad.RescanRequired(); !required || reason == "" {
		t.Fatalf("RescanRequired() = (%v,%q), want (true, non-empty) after errcode=-14", required, reason)
	}
}

// newRejectedByPollAdapter 构造一个已连接的适配器，并经轮询路径把它驱入被拒绝状态。
func newRejectedByPollAdapter(t *testing.T, srv *httptest.Server) *Adapter {
	t.Helper()
	ad := newConnectedAdapter(t, Config{BaseURL: srv.URL, PollInterval: time.Millisecond, BotToken: "tok-old"}, srv)
	rejectByPoll(t, ad)
	return ad
}

// assertRejectedSession 断言「会话被 iLink 拒绝」的可观测契约：未连接、需要重新扫码
// 且有原因、HealthCheck 能把被拒绝状态与未连接区分开、以及 Connect 以
// ErrSessionRejected 拒绝而不是假 OK。
func assertRejectedSession(t *testing.T, ad *Adapter) {
	t.Helper()
	if ad.IsConnected() {
		t.Fatal("IsConnected() = true while iLink rejects the session")
	}
	required, reason := ad.RescanRequired()
	if !required {
		t.Fatal("RescanRequired() = false, want true")
	}
	if reason == "" {
		t.Fatal("RescanRequired() reason is empty, want the re-scan prompt")
	}

	herr := ad.HealthCheck(context.Background())
	if !errors.Is(herr, ErrSessionRejected) {
		t.Fatalf("HealthCheck() = %v, want ErrSessionRejected", herr)
	}
	if errors.Is(herr, adapter.ErrNotConnected) {
		t.Fatal("HealthCheck() also matches ErrNotConnected, want the rejected state to be distinguishable")
	}

	cerr := ad.Connect(context.Background())
	if cerr == nil {
		t.Fatal("Connect() = nil on a rejected session, want ErrSessionRejected (no fake OK)")
	}
	if !errors.Is(cerr, ErrSessionRejected) {
		t.Fatalf("Connect() = %v, want ErrSessionRejected", cerr)
	}
	if errors.Is(cerr, ErrNeedsLogin) {
		t.Fatal("Connect() = ErrNeedsLogin, want ErrSessionRejected (a rejected session is not 'unconfigured')")
	}
	if ad.IsConnected() {
		t.Fatal("IsConnected() = true after a refused Connect on a rejected session")
	}
}

func TestSessionRejected_PollMarksRescanAndRefusesConnect(t *testing.T) {
	t.Parallel()
	srv := rejectingServer(t)
	ad := newRejectedByPollAdapter(t, srv)
	assertRejectedSession(t, ad)
}

func TestSessionRejected_SendMarksRescan(t *testing.T) {
	t.Parallel()
	srv := newJSONServer(t, nil, func(req recordedReq) handlerResult {
		if req.method == http.MethodPost && req.path == "/ilink/bot/sendmessage" {
			return handlerResult{body: jsonBody(map[string]any{"errcode": errcodeSessionRejected})}
		}
		return handlerResult{status: 404}
	})
	ad := newConnectedAdapter(t, Config{BaseURL: srv.URL, BotToken: "tok"}, srv)
	ad.recordInbound("tok-1", adapter.UnifiedMessage{SenderID: "u-1", Timestamp: ad.clock()})

	err := ad.SendMessage(context.Background(), adapter.UnifiedResponse{
		Messages: []adapter.UnifiedMessage{{SenderID: "u-1", Content: "hi"}},
	})
	if !errors.Is(err, ErrSessionRejected) {
		t.Fatalf("SendMessage() = %v, want ErrSessionRejected", err)
	}
	if ad.IsConnected() {
		t.Fatal("IsConnected() = true after a send saw errcode=-14")
	}
	// 之后的发送上报的是会话被拒绝本身，而不是光秃秃的「未连接」。
	err = ad.SendMessage(context.Background(), adapter.UnifiedResponse{
		Messages: []adapter.UnifiedMessage{{SenderID: "u-1", Content: "again"}},
	})
	if !errors.Is(err, ErrSessionRejected) {
		t.Fatalf("second SendMessage() = %v, want ErrSessionRejected", err)
	}
	perr := ad.SendProactive(context.Background(), adapter.UnifiedMessage{SenderID: "u-1", Content: "push"})
	if !errors.Is(perr, ErrSessionRejected) {
		t.Fatalf("SendProactive() = %v, want ErrSessionRejected", perr)
	}
	assertRejectedSession(t, ad)
}

func TestSessionRejected_ClearedByScanLogin(t *testing.T) {
	t.Parallel()
	rec := &reqRecorder{}
	srv := newJSONServer(t, rec, func(req recordedReq) handlerResult {
		switch req.path {
		case "/ilink/bot/getupdates":
			return handlerResult{body: jsonBody(map[string]any{"errcode": errcodeSessionRejected})}
		case "/ilink/bot/get_bot_qrcode":
			return handlerResult{body: jsonBody(map[string]any{
				"qrcode": "qr-re", "qrcode_img_content": "https://img/qr",
			})}
		case "/ilink/bot/get_qrcode_status":
			return handlerResult{body: jsonBody(map[string]any{
				"status": "confirmed", "bot_token": "tok-new",
				"ilink_bot_id": "bot-new", "ilink_user_id": "o-1",
			})}
		}
		return handlerResult{status: 404}
	})
	ad := newRejectedByPollAdapter(t, srv)
	assertRejectedSession(t, ad)

	// 被拒绝的 token 不得短路扫码流程：它不是可用绑定，而 ErrAlreadyLoggedIn 会让
	// 主人无路可退。
	qr, err := ad.StartLogin(context.Background())
	if err != nil {
		t.Fatalf("StartLogin() on a rejected session = %v, want a fresh QR", err)
	}
	if qr.Qrcode != "qr-re" {
		t.Fatalf("StartLogin() qrcode = %q, want qr-re", qr.Qrcode)
	}

	// 确认的扫码交付了新 token：被拒绝状态必须被清除。
	waitFor(t, func() bool { ok, _ := ad.RescanRequired(); return !ok })
	if err := ad.Connect(context.Background()); err != nil {
		t.Fatalf("Connect() after re-scan = %v, want nil", err)
	}
	if !ad.IsConnected() {
		t.Fatal("IsConnected() = false after a confirmed re-scan")
	}
	if err := ad.HealthCheck(context.Background()); err != nil {
		t.Fatalf("HealthCheck() after re-scan = %v, want nil", err)
	}
	if got := ad.Config()["bot_token"]; got != "tok-new" {
		t.Fatalf("bot_token = %v, want tok-new", got)
	}
	if status, _ := ad.LoginStatus(context.Background()); status != LoginStatusConfirmed {
		t.Fatalf("LoginStatus() = %q, want confirmed after a successful re-scan", status)
	}

	// 本次重扫请求的是真正的重新绑定：被拒绝的 token 不作为本地 token 上报（正是
	// 上报它才会招来不带新凭据的 binded_redirect）。
	reqs := rec.find(func(q recordedReq) bool { return q.path == "/ilink/bot/get_bot_qrcode" })
	if len(reqs) != 1 {
		t.Fatalf("get_bot_qrcode requests = %d, want 1", len(reqs))
	}
	if ltl := reqs[0].bodyJSON()["local_token_list"]; ltl == nil {
		t.Fatalf("get_bot_qrcode body has no local_token_list: %s", reqs[0].body)
	} else if list, ok := ltl.([]any); !ok || len(list) != 0 {
		t.Fatalf("get_bot_qrcode local_token_list = %v, want an empty array", ltl)
	}
}

func TestSessionRejected_ClearedByNewToken(t *testing.T) {
	t.Parallel()
	srv := rejectingServer(t)
	ad := newRejectedByPollAdapter(t, srv)

	// 被拒绝的 token 仍在配置中：会话保持被拒绝。
	if err := ad.Connect(context.Background()); !errors.Is(err, ErrSessionRejected) {
		t.Fatalf("Connect() = %v, want ErrSessionRejected while the rejected token is unchanged", err)
	}
	if err := ad.HealthCheck(context.Background()); !errors.Is(err, ErrSessionRejected) {
		t.Fatalf("HealthCheck() = %v, want ErrSessionRejected while the rejected token is unchanged", err)
	}

	setBotToken(ad, "tok-fresh")
	if required, _ := ad.RescanRequired(); required {
		t.Fatal("RescanRequired() = true after a new token was configured")
	}
	if err := ad.Connect(context.Background()); err != nil {
		t.Fatalf("Connect() with a fresh token = %v, want nil", err)
	}
	if !ad.IsConnected() {
		t.Fatal("IsConnected() = false after Connect with a fresh token")
	}
	if err := ad.HealthCheck(context.Background()); err != nil {
		t.Fatalf("HealthCheck() with a fresh token = %v, want nil", err)
	}
}

func TestSessionRejected_LoginStatusReportsRescanAndAllowsRescan(t *testing.T) {
	t.Parallel()
	srv := newJSONServer(t, nil, func(req recordedReq) handlerResult {
		switch req.path {
		case "/ilink/bot/getupdates":
			return handlerResult{body: jsonBody(map[string]any{"errcode": errcodeSessionRejected})}
		case "/ilink/bot/get_bot_qrcode":
			return handlerResult{body: jsonBody(map[string]any{
				"qrcode": "qr-2", "qrcode_img_content": "https://img/qr2",
			})}
		}
		return handlerResult{body: jsonBody(map[string]any{"status": "wait"})}
	})
	ad := newConnectedAdapter(t, Config{
		BaseURL: srv.URL, PollInterval: time.Millisecond,
		LoginInterval: time.Millisecond, LoginTimeout: 30 * time.Millisecond,
		BotToken: "tok-old",
	}, srv)
	rejectByPoll(t, ad)

	// 被拒绝的凭据不得被读作 "confirmed"：否则面板会重新持久化它并把绑定当作成功。
	status, detail := ad.LoginStatus(context.Background())
	if status != LoginStatusFailed {
		t.Fatalf("LoginStatus() = %q, want failed while iLink rejects the stored token", status)
	}
	if detail == "" {
		t.Fatal("LoginStatus() detail is empty, want the re-scan reason")
	}

	// 面板的扫码登录仍必须能生成二维码（ErrAlreadyLoggedIn 会堵死唯一的恢复路径）。
	qr, err := ad.StartLogin(context.Background())
	if err != nil {
		t.Fatalf("StartLogin() = %v, want a fresh QR", err)
	}
	if qr.Qrcode != "qr-2" {
		t.Fatalf("StartLogin() qrcode = %q, want qr-2", qr.Qrcode)
	}
	// 重扫进行期间上报的是它自己的状态，而不是被拒绝状态。
	if status, _ := ad.LoginStatus(context.Background()); status != LoginStatusWaiting {
		t.Fatalf("LoginStatus() during the re-scan = %q, want waiting", status)
	}
}

// setBotToken 替换已配置的 bot token，用来模拟面板保存 + 热重载（会重建适配器）
// 或任何其他原地配置刷新；适配器没有公开的 setter，因为生产环境总是依据新配置构造
// 全新实例。
func setBotToken(ad *Adapter, token string) {
	ad.mu.Lock()
	ad.cfg.BotToken = token
	ad.mu.Unlock()
}