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 setupEmailHandlerTest(t *testing.T) (*EmailChannelHandler, *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.ChannelEmail{},
	))
	t.Cleanup(func() {
		sqlDB, _ := db.DB()
		sqlDB.Close()
	})

	emailRepo := repository.NewChannelEmailRepo(db)
	emailChannelSvc := service.NewChannelEmailService(emailRepo)

	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 := NewEmailChannelHandler(emailChannelSvc, inboxSvc, emailRepo)

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

	return handler, db
}

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

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

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

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

func TestEmailChannel_Create_Success(t *testing.T) {
	handler, db := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)
	accountID := emailAccountID(db)

	body := CreateEmailChannelRequest{
		Email:        "support@example.com",
		IMAPEnabled:  true,
		IMAPAddress:  "imap.example.com",
		IMAPPort:     993,
		IMAPLogin:    "support@example.com",
		IMAPPassword: "imapsecret",
		IMAPSSLMode:  "ssl",
		InboxName:    "Support Email",
	}
	b, _ := json.Marshal(body)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodPost, "/api/v1/accounts/"+accountID+"/email_channels", 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, "Support Email", resp["name"])
	assert.Equal(t, "Channel::Email", resp["channel_type"])
	assert.Equal(t, "support@example.com", resp["email"])
	assert.Equal(t, "imap.example.com", resp["imap_address"])
	require.NotContains(t, resp, "channel")
	require.NotContains(t, resp, "inbox")
}

func TestEmailChannel_Create_InvalidAccountID(t *testing.T) {
	handler, _ := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)

	body := CreateEmailChannelRequest{
		Email: "bad@example.com",
	}
	b, _ := json.Marshal(body)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodPost, "/api/v1/accounts/invalid/email_channels", 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 TestEmailChannel_Create_InvalidRequestBody(t *testing.T) {
	handler, db := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)
	accountID := emailAccountID(db)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodPost, "/api/v1/accounts/"+accountID+"/email_channels", 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 TestEmailChannel_Get_Success(t *testing.T) {
	handler, db := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)
	accountID := emailAccountIDUint(db)

	// Seed a channel and its associated inbox.
	ch := &channelmodel.ChannelEmail{
		Email:       "get@example.com",
		AccountID:   accountID,
		IMAPEnabled: true,
	}
	require.NoError(t, db.Create(ch).Error)
	inbox := createTestChannelInbox(t, db, accountID, ch.ID, "Get Email", "email", map[string]any{
		"email":        "get@example.com",
		"imap_enabled": true,
	})
	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/email_channels/"+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, "Get Email", resp["name"])
	assert.Equal(t, "Channel::Email", resp["channel_type"])
	assert.Equal(t, "get@example.com", resp["email"])
	require.NotContains(t, resp, "channel")
}

func TestEmailChannel_Get_InvalidID(t *testing.T) {
	handler, db := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)
	accountID := emailAccountID(db)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodGet, "/api/v1/accounts/"+accountID+"/inboxes/1/email_channels/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 em_id", resp["error"])
}

func TestEmailChannel_Get_NotFound(t *testing.T) {
	handler, db := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)
	accountID := emailAccountID(db)

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

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

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

func TestEmailChannel_Update_Success(t *testing.T) {
	handler, db := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)
	accountID := emailAccountIDUint(db)

	// Seed a channel and its associated inbox.
	ch := &channelmodel.ChannelEmail{
		Email:       "update@example.com",
		AccountID:   accountID,
		IMAPEnabled: true,
	}
	require.NoError(t, db.Create(ch).Error)
	inbox := createTestChannelInbox(t, db, accountID, ch.ID, "Update Email", "email", map[string]any{
		"email":        "update@example.com",
		"imap_enabled": true,
	})
	ch.InboxID = inbox.ID
	require.NoError(t, db.Save(ch).Error)

	newEmail := "updated@example.com"
	body := UpdateEmailChannelRequest{
		Email: &newEmail,
	}
	b, _ := json.Marshal(body)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodPatch, "/api/v1/accounts/"+strconv.FormatUint(uint64(accountID), 10)+"/inboxes/1/email_channels/"+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, "Channel::Email", resp["channel_type"])
	assert.Equal(t, "updated@example.com", resp["email"])
	require.NotContains(t, resp, "channel")
}

func TestEmailChannel_Update_WrongAccount(t *testing.T) {
	handler, db := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)
	accountID := emailAccountIDUint(db)

	// Seed a channel owned by a different account
	ch := &channelmodel.ChannelEmail{
		Email:     "other@example.com",
		AccountID: accountID + 999,
		InboxID:   302,
	}
	require.NoError(t, db.Create(ch).Error)

	newEmail := "hacked@example.com"
	body := UpdateEmailChannelRequest{
		Email: &newEmail,
	}
	b, _ := json.Marshal(body)

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

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

func TestEmailChannel_Update_InvalidEmID(t *testing.T) {
	handler, db := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)
	accountID := emailAccountID(db)

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

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

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

func TestEmailChannel_Delete_Success(t *testing.T) {
	handler, db := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)
	accountID := emailAccountIDUint(db)

	// Seed a channel
	ch := &channelmodel.ChannelEmail{
		Email:     "delete@example.com",
		AccountID: accountID,
		InboxID:   303,
	}
	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/email_channels/"+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.ChannelEmail{}).Where("id = ?", ch.ID).Count(&count)
	assert.Equal(t, int64(0), count)
}

func TestEmailChannel_Delete_WrongAccount(t *testing.T) {
	handler, db := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)
	accountID := emailAccountIDUint(db)

	// Seed a channel owned by a different account
	ch := &channelmodel.ChannelEmail{
		Email:     "otherdel@example.com",
		AccountID: accountID + 999,
		InboxID:   304,
	}
	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/email_channels/"+strconv.FormatUint(uint64(ch.ID), 10), nil)
	router.ServeHTTP(w, req)

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

func TestEmailChannel_Delete_NotFound(t *testing.T) {
	handler, db := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)
	accountID := emailAccountID(db)

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

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

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

func TestEmailChannel_List_Success(t *testing.T) {
	handler, db := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)
	accountID := emailAccountIDUint(db)

	// Seed multiple channels and their associated inboxes.
	for i := 0; i < 3; i++ {
		ch := &channelmodel.ChannelEmail{
			Email:     "list" + strconv.Itoa(i) + "@example.com",
			AccountID: accountID,
		}
		require.NoError(t, db.Create(ch).Error)
		inbox := createTestChannelInbox(t, db, accountID, ch.ID, "Email List "+strconv.Itoa(i), "email", map[string]any{
			"email": ch.Email,
		})
		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)+"/email_channels", 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 TestEmailChannel_List_InvalidAccountID(t *testing.T) {
	handler, _ := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)

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

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

func TestEmailChannel_List_Empty(t *testing.T) {
	handler, db := setupEmailHandlerTest(t)
	router := setupEmailTestRouter(handler)
	accountID := emailAccountID(db)

	w := httptest.NewRecorder()
	req, _ := http.NewRequest(http.MethodGet, "/api/v1/accounts/"+accountID+"/email_channels", 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)
}