package v1

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

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

	"github.com/gochat/gochat/internal/model"
	"github.com/gochat/gochat/internal/repository"
	"github.com/gochat/gochat/internal/service"
)

type AnalyticsHandlerTestSuite struct {
	suite.Suite
	db        *gorm.DB
	svc       *service.AnalyticsService
	handler   *AnalyticsHandler
	router    *gin.Engine
	accountID uint
}

func TestAnalyticsHandlerTestSuite(t *testing.T) {
	suite.Run(t, new(AnalyticsHandlerTestSuite))
}

func (s *AnalyticsHandlerTestSuite) SetupSuite() {
	db, err := gorm.Open(sqlite.Open(":memory:"), &gorm.Config{})
	s.Require().NoError(err)

	s.db = db
	s.Require().NoError(db.AutoMigrate(
		&model.Account{},
		&model.Conversation{},
		&model.ReportingEvent{},
		&model.ReportingEventsRollup{},
	))

	// Create test account
	acct := model.Account{Name: "TestAccount"}
	s.Require().NoError(db.Create(&acct).Error)
	s.accountID = acct.ID

	eventRepo := repository.NewReportingEventRepo(db)
	rollupRepo := repository.NewReportingEventsRollupRepo(db)
	s.svc = service.NewAnalyticsService(eventRepo, rollupRepo)
	s.handler = NewAnalyticsHandler(s.svc)

	gin.SetMode(gin.TestMode)
	r := gin.New()
	accounts := r.Group("/api/v1/accounts/:account_id")
	accounts.GET("/reports", s.handler.Index)
	accounts.GET("/reports/summary", s.handler.Summary)
	accounts.GET("/reports/agents", s.handler.AgentMetrics)
	accounts.GET("/reports/inboxes", s.handler.InboxMetrics)
	accounts.GET("/reports/labels", s.handler.LabelMetrics)
	accounts.GET("/reports/teams", s.handler.TeamMetrics)
	accounts.GET("/reports/conversation_traffic", s.handler.ConversationTraffic)
	s.router = r
}

func (s *AnalyticsHandlerTestSuite) TearDownSuite() {
	sqlDB, _ := s.db.DB()
	sqlDB.Close()
}

func (s *AnalyticsHandlerTestSuite) SetupTest() {
	s.db.Exec("DELETE FROM reporting_events")
	s.db.Exec("DELETE FROM reporting_events_rollups")
	s.db.Exec("DELETE FROM conversations")
}

// ========== parseAccountID / parseDateRange edge cases ==========

func (s *AnalyticsHandlerTestSuite) TestSummary_InvalidAccountID() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/abc/reports/summary?since=2025-01-01T00:00:00Z&until=2025-01-31T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusBadRequest, w.Code)
}

func (s *AnalyticsHandlerTestSuite) TestSummary_MissingSinceParam() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/1/reports/summary?until=2025-01-31T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusBadRequest, w.Code)
}

func (s *AnalyticsHandlerTestSuite) TestSummary_MissingUntilParam() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/1/reports/summary?since=2025-01-01T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusBadRequest, w.Code)
}

func (s *AnalyticsHandlerTestSuite) TestSummary_InvalidSinceFormat() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/1/reports/summary?since=not-a-date&until=2025-01-31T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusBadRequest, w.Code)
}

func (s *AnalyticsHandlerTestSuite) TestSummary_InvalidUntilFormat() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/1/reports/summary?since=2025-01-01T00:00:00Z&until=not-a-date", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusBadRequest, w.Code)
}

// ========== Summary ==========

func (s *AnalyticsHandlerTestSuite) TestSummary_EmptyData() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/1/reports/summary?since=2025-01-01T00:00:00Z&until=2025-01-31T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusOK, w.Code)

	var body map[string]interface{}
	s.NoError(json.Unmarshal(w.Body.Bytes(), &body))
	s.True(body["success"].(bool))
	data := body["data"].(map[string]interface{})
	s.NotNil(data["metrics"])
}

func (s *AnalyticsHandlerTestSuite) TestSummary_WithData() {
	// Seed a reporting event
	ev := model.ReportingEvent{
		AccountID:            s.accountID,
		Name:                 "first_response",
		Value:                120.5,
		ValueInBusinessHours: 60.0,
		EventStartTime:       parseTime("2025-01-15T10:00:00Z"),
		EventEndTime:         parseTime("2025-01-15T10:02:00Z"),
	}
	s.Require().NoError(s.db.Create(&ev).Error)

	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/1/reports/summary?since=2025-01-01T00:00:00Z&until=2025-02-01T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusOK, w.Code)
}

func (s *AnalyticsHandlerTestSuite) TestIndex_TimeseriesWithData() {
	conv := model.Conversation{AccountID: s.accountID, InboxID: 1, ContactID: 1, Status: string(model.ConversationStatusOpen), ChannelType: "web_widget", Channel: "web_widget"}
	s.Require().NoError(s.db.Create(&conv).Error)
	s.Require().NoError(s.db.Model(&conv).Updates(map[string]interface{}{"created_at": parseTime("2025-01-15T10:00:00Z")}).Error)

	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/1/reports?metric=conversations_count&since=2025-01-01T00:00:00Z&until=2025-02-01T00:00:00Z&type=account&group_by=day", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusOK, w.Code)
	var body map[string]interface{}
	s.NoError(json.Unmarshal(w.Body.Bytes(), &body))
	data := body["data"].([]interface{})
	s.Len(data, 1)
	s.Equal(float64(1), data[0].(map[string]interface{})["value"])
}

// ========== AgentMetrics ==========

func (s *AnalyticsHandlerTestSuite) TestAgentMetrics_InvalidAccountID() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/abc/reports/agents?since=2025-01-01T00:00:00Z&until=2025-01-31T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusBadRequest, w.Code)
}

func (s *AnalyticsHandlerTestSuite) TestAgentMetrics_EmptyData() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/1/reports/agents?since=2025-01-01T00:00:00Z&until=2025-01-31T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusOK, w.Code)
}

// ========== InboxMetrics ==========

func (s *AnalyticsHandlerTestSuite) TestInboxMetrics_InvalidAccountID() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/abc/reports/inboxes?since=2025-01-01T00:00:00Z&until=2025-01-31T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusBadRequest, w.Code)
}

func (s *AnalyticsHandlerTestSuite) TestInboxMetrics_EmptyData() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/1/reports/inboxes?since=2025-01-01T00:00:00Z&until=2025-01-31T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusOK, w.Code)
}

// ========== LabelMetrics ==========

func (s *AnalyticsHandlerTestSuite) TestLabelMetrics_InvalidAccountID() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/abc/reports/labels?since=2025-01-01T00:00:00Z&until=2025-01-31T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusBadRequest, w.Code)
}

func (s *AnalyticsHandlerTestSuite) TestLabelMetrics_EmptyData() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/1/reports/labels?since=2025-01-01T00:00:00Z&until=2025-01-31T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusOK, w.Code)
}

// ========== TeamMetrics ==========

func (s *AnalyticsHandlerTestSuite) TestTeamMetrics_InvalidAccountID() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/abc/reports/teams?since=2025-01-01T00:00:00Z&until=2025-01-31T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusBadRequest, w.Code)
}

func (s *AnalyticsHandlerTestSuite) TestTeamMetrics_EmptyData() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/1/reports/teams?since=2025-01-01T00:00:00Z&until=2025-01-31T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusOK, w.Code)
}

// ========== ConversationTraffic ==========

func (s *AnalyticsHandlerTestSuite) TestConversationTraffic_InvalidAccountID() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/abc/reports/conversation_traffic?since=2025-01-01T00:00:00Z&until=2025-01-31T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusBadRequest, w.Code)
}

func (s *AnalyticsHandlerTestSuite) TestConversationTraffic_EmptyData() {
	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet,
		"/api/v1/accounts/1/reports/conversation_traffic?since=2025-01-01T00:00:00Z&until=2025-01-31T00:00:00Z", nil)
	s.router.ServeHTTP(w, req)
	s.Equal(http.StatusOK, w.Code)
}

// ========== Nil service guard ==========

func (s *AnalyticsHandlerTestSuite) TestNilService() {
	h := NewAnalyticsHandler(nil)
	// Handler with nil svc will panic on method calls — skip creating a router
	// Instead just verify NewAnalyticsHandler(nil) doesn't panic at construction
	s.NotNil(h)
}

func parseTime(s string) time.Time {
	t, _ := time.Parse(time.RFC3339, s)
	return t
}