package gateway

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

	"github.com/alicebob/miniredis/v2"
	"github.com/gin-gonic/gin"
	"github.com/glebarez/sqlite"
	"github.com/gorilla/websocket"
	"github.com/redis/go-redis/v9"
	"gorm.io/gorm"

	"dudu/server/internal/asr"
	"dudu/server/internal/quota"
	"dudu/server/internal/store"
	"dudu/server/pkg/protocol"
)

func setup(t *testing.T) (*httptest.Server, *gorm.DB, *redis.Client) {
	t.Helper()
	gin.SetMode(gin.TestMode)
	mr := miniredis.RunT(t)
	rdb := redis.NewClient(&redis.Options{Addr: mr.Addr()})
	db, err := gorm.Open(sqlite.Open(":memory:"), &gorm.Config{})
	if err != nil {
		t.Fatal(err)
	}
	if err := db.AutoMigrate(store.AllModels()...); err != nil {
		t.Fatal(err)
	}
	db.Create(&store.User{ID: "u1", BalanceSeconds: 600})

	mock := asr.NewMock()
	mock.Script = []string{"你好，世界。"}
	h := &Handler{Provider: mock, Quota: quota.New(rdb, db), RDB: rdb}

	r := gin.New()
	// 测试中跳过 JWT，直接注入 uid
	r.GET("/v1/asr/stream", func(c *gin.Context) {
		c.Set("auth.user_id", "u1")
		h.HandleWS(c)
	})
	srv := httptest.NewServer(r)
	t.Cleanup(srv.Close)
	return srv, db, rdb
}

func dial(t *testing.T, srv *httptest.Server) *websocket.Conn {
	t.Helper()
	url := "ws" + strings.TrimPrefix(srv.URL, "http") + "/v1/asr/stream?device_id=dev1"
	conn, _, err := websocket.DefaultDialer.Dial(url, nil)
	if err != nil {
		t.Fatal(err)
	}
	t.Cleanup(func() { conn.Close() })
	return conn
}

func TestStreamE2E(t *testing.T) {
	srv, db, _ := setup(t)
	conn := dial(t, srv)

	start, _ := json.Marshal(protocol.ClientMsg{Type: "start", SessionID: "s1", SampleRate: 16000, Format: "pcm16"})
	if err := conn.WriteMessage(websocket.TextMessage, start); err != nil {
		t.Fatal(err)
	}
	// 推 10 帧（1s 音频）→ mock 识别完 6 字全句
	frame := make([]byte, protocol.FrameBytes)
	for i := 0; i < 10; i++ {
		if err := conn.WriteMessage(websocket.BinaryMessage, frame); err != nil {
			t.Fatal(err)
		}
	}
	stop, _ := json.Marshal(protocol.ClientMsg{Type: "stop", SessionID: "s1"})
	if err := conn.WriteMessage(websocket.TextMessage, stop); err != nil {
		t.Fatal(err)
	}

	var partials, finals []string
	var lastUsage protocol.ServerMsg
	deadline := time.Now().Add(5 * time.Second)
	for time.Now().Before(deadline) {
		_ = conn.SetReadDeadline(time.Now().Add(2 * time.Second))
		var msg protocol.ServerMsg
		if err := conn.ReadJSON(&msg); err != nil {
			break
		}
		switch msg.Type {
		case protocol.MsgPartial:
			partials = append(partials, msg.Text)
		case protocol.MsgFinal:
			finals = append(finals, msg.Text)
		case protocol.MsgUsage:
			lastUsage = msg
		case protocol.MsgError:
			t.Fatalf("unexpected error frame: %+v", msg)
		}
		if lastUsage.SessionSeconds > 0 && len(finals) >= 2 {
			break
		}
	}

	if len(partials) == 0 {
		t.Fatal("expect partial frames")
	}
	if got := strings.Join(finals, ""); got != "你好，世界。" {
		t.Fatalf("final mismatch: %q", got)
	}
	if lastUsage.SessionSeconds != 1 {
		t.Fatalf("want usage 1s, got %d", lastUsage.SessionSeconds)
	}
	// trial 先扣：余额应不变（600），试用剩 179
	if lastUsage.BalanceSeconds != 600 || lastUsage.TrialRemaining != protocol.TrialDailySeconds-1 {
		t.Fatalf("unexpected usage: %+v", lastUsage)
	}

	// 异步 settle 落库
	var sess store.ASRSession
	for i := 0; i < 50; i++ {
		if err := db.First(&sess, "id = ?", "s1").Error; err == nil {
			break
		}
		time.Sleep(20 * time.Millisecond)
	}
	if sess.AudioSeconds != 1 || sess.TrialPart != 1 || sess.BalancePart != 0 {
		t.Fatalf("settle mismatch: %+v", sess)
	}
	// 计量交叉校验：provider 时间戳已落库，且不超过实收音频时长
	if sess.ProviderMs <= 0 || sess.ProviderMs > int64(sess.AudioSeconds)*1000 {
		t.Fatalf("provider ms cross-check mismatch: %+v", sess)
	}
}

func TestQuotaExceededOnStart(t *testing.T) {
	srv, db, _ := setup(t)
	// 用尽试用 + 余额
	db.Model(&store.User{}).Where("id = ?", "u1").Update("balance_seconds", 0)
	mrConsumeAll(t, srv, db)

	conn := dial(t, srv)
	start, _ := json.Marshal(protocol.ClientMsg{Type: "start", SessionID: "s9", SampleRate: 16000})
	_ = conn.WriteMessage(websocket.TextMessage, start)
	var msg protocol.ServerMsg
	_ = conn.SetReadDeadline(time.Now().Add(2 * time.Second))
	if err := conn.ReadJSON(&msg); err != nil {
		t.Fatal(err)
	}
	if msg.Type != protocol.MsgError || msg.Code != protocol.ErrQuotaExceeded {
		t.Fatalf("want QUOTA_EXCEEDED, got %+v", msg)
	}
}

// mrConsumeAll 把 u1 的当日试用耗尽（经 quota 通道，保证键一致）。
// 单会话被截断在略低于 180s 处（截断帧不再计费，16A），故一会话不足以扣满 180s 试用；
// 此处循环开会话推音频，直到某个 usage 帧报告 TrialRemaining<=0 为止。
func mrConsumeAll(t *testing.T, srv *httptest.Server, db *gorm.DB) {
	t.Helper()
	frame := make([]byte, protocol.FrameBytes)
	deadline := time.Now().Add(15 * time.Second)
	for sess := 0; sess < 5 && time.Now().Before(deadline); sess++ {
		conn := dial(t, srv)
		sid := "s0_" + string(rune('a'+sess))
		start, _ := json.Marshal(protocol.ClientMsg{Type: "start", SessionID: sid, SampleRate: 16000})
		_ = conn.WriteMessage(websocket.TextMessage, start)
		// 推 180s 音频（1800 帧）→ 会话在临界处截断
		for i := 0; i < protocol.TrialDailySeconds*10; i++ {
			if err := conn.WriteMessage(websocket.BinaryMessage, frame); err != nil {
				break
			}
		}
		stop, _ := json.Marshal(protocol.ClientMsg{Type: "stop", SessionID: sid})
		_ = conn.WriteMessage(websocket.TextMessage, stop)

		exhausted := false
		for time.Now().Before(deadline) {
			_ = conn.SetReadDeadline(time.Now().Add(2 * time.Second))
			var msg protocol.ServerMsg
			if err := conn.ReadJSON(&msg); err != nil {
				break
			}
			if msg.Type == protocol.MsgUsage && msg.TrialRemaining <= 0 {
				exhausted = true
				break
			}
		}
		conn.Close()
		if exhausted {
			return
		}
	}
	t.Fatal("failed to exhaust trial via repeated sessions")
}

func TestSessionLimitTruncates(t *testing.T) {
	srv, _, _ := setup(t)
	conn := dial(t, srv)
	start, _ := json.Marshal(protocol.ClientMsg{Type: "start", SessionID: "s2", SampleRate: 16000})
	_ = conn.WriteMessage(websocket.TextMessage, start)
	frame := make([]byte, protocol.FrameBytes)
	// 181s 音频 → 触发截断
	for i := 0; i < 1810; i++ {
		if err := conn.WriteMessage(websocket.BinaryMessage, frame); err != nil {
			t.Fatal(err)
		}
	}
	sawLimit := false
	deadline := time.Now().Add(5 * time.Second)
	for time.Now().Before(deadline) && !sawLimit {
		_ = conn.SetReadDeadline(time.Now().Add(2 * time.Second))
		var msg protocol.ServerMsg
		if err := conn.ReadJSON(&msg); err != nil {
			break
		}
		if msg.Type == protocol.MsgError && msg.Code == protocol.ErrSessionLimit {
			sawLimit = true
		}
	}
	if !sawLimit {
		t.Fatal("expect SESSION_LIMIT after 180s audio")
	}
}

func TestConcurrentSecondSessionRejected(t *testing.T) {
	srv, _, _ := setup(t)
	c1 := dial(t, srv)
	start1, _ := json.Marshal(protocol.ClientMsg{Type: "start", SessionID: "a1", SampleRate: 16000})
	_ = c1.WriteMessage(websocket.TextMessage, start1)
	// 等会话真正建立（收到任意帧前先推一帧拿 partial）
	frame := make([]byte, protocol.FrameBytes)
	_ = c1.WriteMessage(websocket.BinaryMessage, frame)
	time.Sleep(100 * time.Millisecond)

	c2 := dial(t, srv) // 同 device_id=dev1
	start2, _ := json.Marshal(protocol.ClientMsg{Type: "start", SessionID: "a2", SampleRate: 16000})
	_ = c2.WriteMessage(websocket.TextMessage, start2)
	var msg protocol.ServerMsg
	_ = c2.SetReadDeadline(time.Now().Add(2 * time.Second))
	if err := c2.ReadJSON(&msg); err != nil {
		t.Fatal(err)
	}
	if msg.Type != protocol.MsgError || msg.Code != protocol.ErrRateLimited {
		t.Fatalf("want RATE_LIMITED for concurrent session, got %+v", msg)
	}
}