package services

import (
	"math"
	"testing"
	"time"
)

func TestMetricsServiceGetDashboardMetrics(t *testing.T) {
	store := newTestStore(t)
	service := NewMetricsService(store)
	today := localDayStart(time.Now())
	yesterday := today.AddDate(0, 0, -1)

	insertImageTaskForMetrics(t, store, imageTaskStatusSucceeded, 1000, today.Add(2*time.Hour))
	insertImageTaskForMetrics(t, store, imageTaskStatusSucceeded, 2000, today.Add(3*time.Hour))
	insertImageTaskForMetrics(t, store, imageTaskStatusFailed, 0, today.Add(4*time.Hour))
	insertImageTaskForMetrics(t, store, imageTaskStatusSucceeded, 900, yesterday.Add(2*time.Hour))
	insertAuditLogForMetrics(t, store, today.Add(5*time.Hour))
	insertAuditLogForMetrics(t, store, today.Add(6*time.Hour))
	insertAuditLogForMetrics(t, store, yesterday.Add(5*time.Hour))

	metrics, err := service.GetDashboardMetrics()
	if err != nil {
		t.Fatalf("get dashboard metrics: %v", err)
	}

	if metrics.TodayProcessedImages != 3 {
		t.Fatalf("today processed images = %d, want 3", metrics.TodayProcessedImages)
	}
	if metrics.FailedTasks != 1 {
		t.Fatalf("failed tasks = %d, want 1", metrics.FailedTasks)
	}
	if math.Abs(metrics.SuccessRate-66.6667) > 0.01 {
		t.Fatalf("success rate = %f, want about 66.67", metrics.SuccessRate)
	}
	if metrics.AverageDurationMs != 1500 {
		t.Fatalf("average duration = %f, want 1500", metrics.AverageDurationMs)
	}
	if metrics.TodayAuditLogs != 2 {
		t.Fatalf("today audit logs = %d, want 2", metrics.TodayAuditLogs)
	}
}

func TestMetricsServiceGetProcessingTrend(t *testing.T) {
	store := newTestStore(t)
	service := NewMetricsService(store)
	today := localDayStart(time.Now())
	twoDaysAgo := today.AddDate(0, 0, -2)

	insertImageTaskForMetrics(t, store, imageTaskStatusSucceeded, 1200, twoDaysAgo.Add(2*time.Hour))
	insertImageTaskForMetrics(t, store, imageTaskStatusFailed, 0, today.Add(2*time.Hour))
	insertAuditLogForMetrics(t, store, today.Add(3*time.Hour))

	trend, err := service.GetProcessingTrend(3)
	if err != nil {
		t.Fatalf("get processing trend: %v", err)
	}
	if len(trend) != 3 {
		t.Fatalf("trend len = %d, want 3", len(trend))
	}
	if trend[0].Date != twoDaysAgo.Format("2006-01-02") {
		t.Fatalf("first date = %q, want %q", trend[0].Date, twoDaysAgo.Format("2006-01-02"))
	}
	if trend[0].ProcessedImages != 1 || trend[0].SucceededTasks != 1 {
		t.Fatalf("first metric = %+v, want one succeeded task", trend[0])
	}
	if trend[2].ProcessedImages != 1 || trend[2].FailedTasks != 1 || trend[2].AuditLogs != 1 {
		t.Fatalf("today metric = %+v, want one failed task and one audit log", trend[2])
	}
}

func TestNormalizeTrendDays(t *testing.T) {
	if got := normalizeTrendDays(0); got != defaultTrendDays {
		t.Fatalf("normalize 0 = %d, want %d", got, defaultTrendDays)
	}
	if got := normalizeTrendDays(maxTrendDays + 1); got != maxTrendDays {
		t.Fatalf("normalize max+1 = %d, want %d", got, maxTrendDays)
	}
	if got := normalizeTrendDays(3); got != 3 {
		t.Fatalf("normalize 3 = %d, want 3", got)
	}
}

func insertImageTaskForMetrics(t *testing.T, store *SuiStore, status string, durationMs int64, createdAt time.Time) {
	t.Helper()

	_, err := store.DB.Exec(`
		INSERT INTO image_tasks (source_path, status, operation, duration_ms, error_message, created_at, updated_at)
		VALUES (?, ?, 'enhance', ?, '', ?, ?)
	`, "D:/images/sku.jpg", status, durationMs, formatMetricTime(createdAt), formatMetricTime(createdAt))
	if err != nil {
		t.Fatalf("insert image task: %v", err)
	}
}

func insertAuditLogForMetrics(t *testing.T, store *SuiStore, createdAt time.Time) {
	t.Helper()

	_, err := store.DB.Exec(`
		INSERT INTO audit_logs (actor, action, target_type, target_id, detail, created_at)
		VALUES ('admin', 'image_task.create', 'image_task', '1', 'created', ?)
	`, formatMetricTime(createdAt))
	if err != nil {
		t.Fatalf("insert audit log: %v", err)
	}
}