package v1

import (
	"bytes"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"strconv"
	"testing"

	"github.com/gin-gonic/gin"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"gorm.io/driver/sqlite"
	"gorm.io/gorm"

	"github.com/gochat/gochat/internal/model"
	channelmodel "github.com/gochat/gochat/internal/model/channel"

	"github.com/gochat/gochat/internal/channel/whatsapp"
	"github.com/gochat/gochat/internal/repository"
	"github.com/gochat/gochat/internal/service"
)

// ── Setup helpers ────────────────────────────────────────────────

func setupLINEHandlerTest(t *testing.T) (*LINEChannelHandler, *gorm.DB) {
	t.Helper()
	db, err := gorm.Open(sqlite.Open("file::memory:?cache=shared"), &gorm.Config{})
	require.NoError(t, err)

	require.NoError(t, db.AutoMigrate(
		&model.Account{},
		&model.Inbox{},
		&model.AgentBot{},
		&model.AgentBotInbox{},
		&model.WebhookSubscription{},
		&channelmodel.ChannelLINE{},
	))
	t.Cleanup(func() {
		sqlDB, _ := db.DB()
		sqlDB.Close()
	})

	lineRepo := repository.NewChannelLINERepo(db)
	lineChannelSvc := service.NewChannelLINEService(lineRepo)

	inboxRepo := repository.NewInboxRepo(db)
	agentBotInboxRepo := repository.NewAgentBotInboxRepo(db)
	agentBotRepo := repository.NewAgentBotRepo(db)
	campaignRepo := repository.NewCampaignRepo(db)
	webhookSubRepo := repository.NewWebhookSubscriptionRepo(db)
	waRepo := whatsapp.NewRepository(db)
	waService := whatsapp.NewWhatsAppService(waRepo)
	inboxSvc := service.NewInboxService(inboxRepo, agentBotInboxRepo, agentBotRepo, campaignRepo, webhookSubRepo, waService, waRepo)

	handler := NewLINEChannelHandler(lineChannelSvc, nil, inboxSvc, lineRepo)

	// Seed an account
	account := &model.Account{Name: "LINETestOrg", Locale: "en", Active: true}
	require.NoError(t, db.Create(account).Error)

	return handler, db
}

func lineAccountID(db *gorm.DB) string {
	var account model.Account
	db.First(&account)
	return strconv.FormatUint(uint64(account.ID), 10)
}

func lineAccountIDUint(db *gorm.DB) uint {
	var account model.Account
	db.First(&account)
	return account.ID
}

func setupLINETestRouter(handler *LINEChannelHandler) *gin.Engine {
	gin.SetMode(gin.TestMode)
	r := gin.New()
	ag := r.Group("/api/v1/accounts/:id")
	ag.POST("/line_channel", handler.Create)
	ag.GET("/line_channel", handler.List)
	ig := ag.Group("/inboxes/:inbox_id/line_channel")
	ig.GET("/:line_id", handler.Get)
	ig.PATCH("/:line_id", handler.Update)
	ig.DELETE("/:line_id", handler.Delete)
	return r
}

// ── Create ──────────────────────────────────────────────────────

func TestLINEChannel_Create_Success(t *testing.T) {
	handler, db := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)
	accountID := lineAccountID(db)

	body := CreateLINEChannelRequest{
		ChannelID:          "line_chan_123",
		Name:               "LINE Official",
		ChannelAccessToken: "access_token_secret",
		ChannelSecret:      "secret_value",
	}
	b, _ := json.Marshal(body)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodPost, "/api/v1/accounts/"+accountID+"/line_channel", bytes.NewReader(b))
	req.Header.Set("Content-Type", "application/json")
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusOK, w.Code)

	var resp map[string]interface{}
	require.NoError(t, json.Unmarshal(w.Body.Bytes(), &resp))
	assert.Equal(t, "LINE Official", resp["name"])
	assert.Equal(t, "Channel::Line", resp["channel_type"])
	assert.Equal(t, "line_chan_123", resp["line_channel_id"])
	assert.Equal(t, "secret_value", resp["line_channel_secret"])
	assert.Equal(t, "access_token_secret", resp["line_channel_token"])
	require.NotContains(t, resp, "channel")
	require.NotContains(t, resp, "inbox")
}

func TestLINEChannel_CreateRejectsAccountInboxLimitWithoutChannelOrphan(t *testing.T) {
	handler, db := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)
	accountID := lineAccountIDUint(db)
	require.NoError(t, db.Model(&model.Account{}).Where("id = ?", accountID).Update("inbox_limit", 1).Error)
	require.NoError(t, db.Create(&model.Inbox{AccountID: accountID, Name: "Existing", ChannelType: "api"}).Error)

	body := CreateLINEChannelRequest{
		ChannelID:          "line_limit_123",
		Name:               "Blocked LINE",
		ChannelAccessToken: "access_token_secret",
		ChannelSecret:      "secret_value",
	}
	b, _ := json.Marshal(body)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodPost, "/api/v1/accounts/"+strconv.FormatUint(uint64(accountID), 10)+"/line_channel", bytes.NewReader(b))
	req.Header.Set("Content-Type", "application/json")
	router.ServeHTTP(w, req)

	require.Equal(t, http.StatusPaymentRequired, w.Code, w.Body.String())
	var resp map[string]interface{}
	require.NoError(t, json.Unmarshal(w.Body.Bytes(), &resp))
	require.Equal(t, service.InboxLimitExceededMessage, resp["error"])
	var inboxCount int64
	require.NoError(t, db.Model(&model.Inbox{}).Where("account_id = ?", accountID).Count(&inboxCount).Error)
	require.Equal(t, int64(1), inboxCount)
	var channelCount int64
	require.NoError(t, db.Model(&channelmodel.ChannelLINE{}).Where("account_id = ?", accountID).Count(&channelCount).Error)
	require.Equal(t, int64(0), channelCount)
}

func TestLINEChannel_Create_InvalidAccountID(t *testing.T) {
	handler, _ := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)

	body := CreateLINEChannelRequest{
		ChannelID:          "line_bad",
		Name:               "Bad Account",
		ChannelAccessToken: "token",
		ChannelSecret:      "secret",
	}
	b, _ := json.Marshal(body)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodPost, "/api/v1/accounts/invalid/line_channel", bytes.NewReader(b))
	req.Header.Set("Content-Type", "application/json")
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusBadRequest, w.Code)
	var resp map[string]interface{}
	require.NoError(t, json.Unmarshal(w.Body.Bytes(), &resp))
	assert.Equal(t, "invalid account_id", resp["error"])
}

func TestLINEChannel_Create_InvalidRequestBody(t *testing.T) {
	handler, db := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)
	accountID := lineAccountID(db)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodPost, "/api/v1/accounts/"+accountID+"/line_channel", bytes.NewReader([]byte("{bad json")))
	req.Header.Set("Content-Type", "application/json")
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusBadRequest, w.Code)
}

// ── Get ──────────────────────────────────────────────────────────

func TestLINEChannel_Get_Success(t *testing.T) {
	handler, db := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)
	accountID := lineAccountIDUint(db)

	// Seed a channel and its associated inbox.
	ch := &channelmodel.ChannelLINE{
		ChannelID: "line_get_123",
		Name:      "LINE Get Test",
		AccountID: accountID,
	}
	require.NoError(t, db.Create(ch).Error)
	inbox := createTestChannelInbox(t, db, accountID, ch.ID, "LINE Get Test", "line", map[string]any{
		"line_channel_id":     "line_get_123",
		"line_channel_secret": "line-secret",
		"line_channel_token":  "line-token",
		"channel_secret":      "line-secret",
	})
	ch.InboxID = inbox.ID
	require.NoError(t, db.Save(ch).Error)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodGet, "/api/v1/accounts/"+strconv.FormatUint(uint64(accountID), 10)+"/inboxes/1/line_channel/"+strconv.FormatUint(uint64(ch.ID), 10), nil)
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusOK, w.Code)
	var resp map[string]interface{}
	require.NoError(t, json.Unmarshal(w.Body.Bytes(), &resp))
	assert.Equal(t, "LINE Get Test", resp["name"])
	assert.Equal(t, "Channel::Line", resp["channel_type"])
	assert.Equal(t, "line_get_123", resp["line_channel_id"])
	require.NotContains(t, resp, "channel")
}

func TestLINEChannel_Get_InvalidID(t *testing.T) {
	handler, db := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)
	accountID := lineAccountID(db)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodGet, "/api/v1/accounts/"+accountID+"/inboxes/1/line_channel/invalid", nil)
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusBadRequest, w.Code)
	var resp map[string]interface{}
	require.NoError(t, json.Unmarshal(w.Body.Bytes(), &resp))
	assert.Equal(t, "invalid line_id", resp["error"])
}

func TestLINEChannel_Get_NotFound(t *testing.T) {
	handler, db := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)
	accountID := lineAccountID(db)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodGet, "/api/v1/accounts/"+accountID+"/inboxes/1/line_channel/99999", nil)
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusNotFound, w.Code)
}

// ── Update ──────────────────────────────────────────────────────

func TestLINEChannel_Update_Success(t *testing.T) {
	handler, db := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)
	accountID := lineAccountIDUint(db)

	// Seed a channel and its associated inbox.
	ch := &channelmodel.ChannelLINE{
		ChannelID: "line_upd_123",
		Name:      "LINE Update Test",
		AccountID: accountID,
	}
	require.NoError(t, db.Create(ch).Error)
	inbox := createTestChannelInbox(t, db, accountID, ch.ID, "LINE Update Test", "line", map[string]any{
		"line_channel_id":     "line_upd_123",
		"line_channel_secret": "old-secret",
		"line_channel_token":  "old-token",
		"channel_secret":      "old-secret",
	})
	ch.InboxID = inbox.ID
	require.NoError(t, db.Save(ch).Error)

	body := UpdateLINEChannelRequest{
		Name: "Updated LINE",
	}
	b, _ := json.Marshal(body)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodPatch, "/api/v1/accounts/"+strconv.FormatUint(uint64(accountID), 10)+"/inboxes/1/line_channel/"+strconv.FormatUint(uint64(ch.ID), 10), bytes.NewReader(b))
	req.Header.Set("Content-Type", "application/json")
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusOK, w.Code)
	var resp map[string]interface{}
	require.NoError(t, json.Unmarshal(w.Body.Bytes(), &resp))
	assert.Equal(t, "Updated LINE", resp["name"])
	assert.Equal(t, "line_upd_123", resp["line_channel_id"])
	assert.Equal(t, "old-secret", resp["line_channel_secret"])
	require.NotContains(t, resp, "channel")
}

func TestLINEChannel_Update_WrongAccount(t *testing.T) {
	handler, db := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)
	accountID := lineAccountIDUint(db)

	// Seed a channel owned by a different account
	ch := &channelmodel.ChannelLINE{
		ChannelID: "line_other",
		Name:      "LINE Other",
		AccountID: accountID + 999,
		InboxID:   702,
	}
	require.NoError(t, db.Create(ch).Error)

	// The handler now correctly rejects cross-account updates.
	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodPatch, "/api/v1/accounts/"+strconv.FormatUint(uint64(accountID), 10)+"/inboxes/1/line_channel/"+strconv.FormatUint(uint64(ch.ID), 10), nil)
	req.Header.Set("Content-Type", "application/json")
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusForbidden, w.Code)
}

func TestLINEChannel_Update_InvalidLineID(t *testing.T) {
	handler, db := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)
	accountID := lineAccountID(db)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodPatch, "/api/v1/accounts/"+accountID+"/inboxes/1/line_channel/invalid", bytes.NewReader([]byte("{}")))
	req.Header.Set("Content-Type", "application/json")
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusBadRequest, w.Code)
}

// ── Delete ──────────────────────────────────────────────────────

func TestLINEChannel_Delete_Success(t *testing.T) {
	handler, db := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)
	accountID := lineAccountIDUint(db)

	// Seed a channel
	ch := &channelmodel.ChannelLINE{
		ChannelID: "line_del_123",
		Name:      "LINE Delete Test",
		AccountID: accountID,
		InboxID:   703,
	}
	require.NoError(t, db.Create(ch).Error)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodDelete, "/api/v1/accounts/"+strconv.FormatUint(uint64(accountID), 10)+"/inboxes/1/line_channel/"+strconv.FormatUint(uint64(ch.ID), 10), nil)
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusOK, w.Code)

	// Verify channel is soft-deleted
	var count int64
	db.Model(&channelmodel.ChannelLINE{}).Where("id = ?", ch.ID).Count(&count)
	assert.Equal(t, int64(0), count)
}

func TestLINEChannel_Delete_WrongAccount(t *testing.T) {
	handler, db := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)
	accountID := lineAccountIDUint(db)

	// Seed a channel owned by a different account
	ch := &channelmodel.ChannelLINE{
		ChannelID: "line_other_del",
		Name:      "LINE Other Del",
		AccountID: accountID + 999,
		InboxID:   704,
	}
	require.NoError(t, db.Create(ch).Error)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodDelete, "/api/v1/accounts/"+strconv.FormatUint(uint64(accountID), 10)+"/inboxes/1/line_channel/"+strconv.FormatUint(uint64(ch.ID), 10), nil)
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusForbidden, w.Code)
}

func TestLINEChannel_Delete_NotFound(t *testing.T) {
	handler, db := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)
	accountID := lineAccountID(db)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodDelete, "/api/v1/accounts/"+accountID+"/inboxes/1/line_channel/99999", nil)
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusNotFound, w.Code)
}

// ── List ──────────────────────────────────────────────────────

func TestLINEChannel_List_Success(t *testing.T) {
	handler, db := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)
	accountID := lineAccountIDUint(db)

	// Seed multiple channels and their associated inboxes.
	for i := 0; i < 3; i++ {
		ch := &channelmodel.ChannelLINE{
			ChannelID: "line_list_" + strconv.Itoa(i),
			Name:      "LINE List " + strconv.Itoa(i),
			AccountID: accountID,
		}
		require.NoError(t, db.Create(ch).Error)
		inbox := createTestChannelInbox(t, db, accountID, ch.ID, ch.Name, "line", map[string]any{
			"line_channel_id":     ch.ChannelID,
			"line_channel_secret": "line-secret-" + strconv.Itoa(i),
			"line_channel_token":  "line-token-" + strconv.Itoa(i),
			"channel_secret":      "line-secret-" + strconv.Itoa(i),
		})
		ch.InboxID = inbox.ID
		require.NoError(t, db.Save(ch).Error)
	}

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodGet, "/api/v1/accounts/"+strconv.FormatUint(uint64(accountID), 10)+"/line_channel", nil)
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusOK, w.Code)
	var resp map[string]interface{}
	require.NoError(t, json.Unmarshal(w.Body.Bytes(), &resp))
	channels, ok := resp["payload"].([]interface{})
	require.True(t, ok)
	assert.Len(t, channels, 3)
}

func TestLINEChannel_List_InvalidAccountID(t *testing.T) {
	handler, _ := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodGet, "/api/v1/accounts/invalid/line_channel", nil)
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusBadRequest, w.Code)
}

func TestLINEChannel_List_Empty(t *testing.T) {
	handler, db := setupLINEHandlerTest(t)
	router := setupLINETestRouter(handler)
	accountID := lineAccountID(db)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodGet, "/api/v1/accounts/"+accountID+"/line_channel", nil)
	router.ServeHTTP(w, req)

	assert.Equal(t, http.StatusOK, w.Code)
	var resp map[string]interface{}
	require.NoError(t, json.Unmarshal(w.Body.Bytes(), &resp))
	channels, ok := resp["payload"].([]interface{})
	require.True(t, ok)
	assert.Len(t, channels, 0)
}