package model

import (
	"fmt"
	"testing"
	"time"
)

// The model package shares a single in-memory SQLite across all tests
// via TestMain in task_cas_test.go. We MUST NOT swap DB out or null
// it in Cleanup — doing so wedges every other test in the package.
//
// Strategy: AutoMigrate the audit table once (idempotent on SQLite),
// then DELETE rows at the top of each test to isolate cases.

func setupAuditTest(t *testing.T) {
	t.Helper()
	if err := DB.AutoMigrate(&AgentAuditEvent{}); err != nil {
		t.Fatalf("migrate: %v", err)
	}
	if err := DB.Exec("DELETE FROM agent_audit_events").Error; err != nil {
		t.Fatalf("truncate: %v", err)
	}
}

func TestInsertAgentAuditEvent_PersistsRow(t *testing.T) {
	// Regression for H1 — the previous implementation appended to an
	// in-process map that was wiped on every container restart. This
	// test pins the new behaviour: rows survive in DB.
	setupAuditTest(t)

	evt := &AgentAuditEvent{
		EventID:       "evt_test_001",
		Event:         "deployment.accepted",
		Actor:         "agent_control_plane",
		Resource:      "dep_abc",
		UserID:        "user-42",
		ChannelID:     "channel-1",
		BindingScope:  "project-main",
		DeploymentID:  "dep_abc",
		CorrelationID: "corr-xyz",
		RequestID:     "req-001",
	}
	InsertAgentAuditEvent(evt)

	var got AgentAuditEvent
	if err := DB.Where("event_id = ?", "evt_test_001").First(&got).Error; err != nil {
		t.Fatalf("not persisted: %v", err)
	}
	if got.Result != "ok" {
		t.Errorf("default Result should be 'ok', got %q", got.Result)
	}
	if got.SchemaVersion != 1 {
		t.Errorf("default SchemaVersion should be 1, got %d", got.SchemaVersion)
	}
	if got.OccurredAt == 0 {
		t.Errorf("OccurredAt should be auto-stamped, got 0")
	}
}

func TestInsertAgentAuditEvent_NilGuards(t *testing.T) {
	// Production safety: audit writes run inside hot paths (right
	// after a deployment mutation). A nil DB or nil event MUST NOT
	// panic — better to drop the audit row than to fail the user
	// API call.
	defer func() {
		if r := recover(); r != nil {
			t.Fatalf("InsertAgentAuditEvent panicked: %v", r)
		}
	}()
	InsertAgentAuditEvent(nil) // nil evt
	prev := DB
	DB = nil
	InsertAgentAuditEvent(&AgentAuditEvent{EventID: "x"}) // nil DB
	DB = prev
}

func TestListAgentAuditEvents_FilterAndPaginate(t *testing.T) {
	setupAuditTest(t)

	now := time.Now().UnixMilli()
	for i := 0; i < 5; i++ {
		uid := "user-A"
		if i%2 == 0 {
			uid = "user-B"
		}
		InsertAgentAuditEvent(&AgentAuditEvent{
			EventID:      fmt.Sprintf("evt_%d", i),
			Event:        "deployment.accepted",
			UserID:       uid,
			DeploymentID: "dep_X",
			OccurredAt:   now + int64(i)*1000,
		})
	}

	// All rows visible without filter.
	rows, total, err := ListAgentAuditEvents(ListAgentAuditEventsFilter{})
	if err != nil {
		t.Fatalf("list: %v", err)
	}
	if total != 5 || len(rows) != 5 {
		t.Errorf("expected 5 rows, got total=%d len=%d", total, len(rows))
	}

	// user_id filter narrows to 3 (i=0,2,4 → user-B).
	_, total, err = ListAgentAuditEvents(ListAgentAuditEventsFilter{UserID: "user-B"})
	if err != nil {
		t.Fatalf("list with userid: %v", err)
	}
	if total != 3 {
		t.Errorf("user-B should have 3 rows, got %d", total)
	}

	// Newest-first ordering. evt_4 inserted last → top.
	rows, _, _ = ListAgentAuditEvents(ListAgentAuditEventsFilter{})
	if rows[0].EventID != "evt_4" {
		t.Errorf("expected newest-first, got %q on top", rows[0].EventID)
	}
}

func TestListAgentAuditEventsByDeployment_Chronological(t *testing.T) {
	// Detail-drawer reads need oldest-first for a top-to-bottom
	// timeline. Confirms ascending order independent of insertion
	// order.
	setupAuditTest(t)

	InsertAgentAuditEvent(&AgentAuditEvent{
		EventID: "evt_late", Event: "x", DeploymentID: "dep_T",
		OccurredAt: 9000,
	})
	InsertAgentAuditEvent(&AgentAuditEvent{
		EventID: "evt_early", Event: "x", DeploymentID: "dep_T",
		OccurredAt: 1000,
	})

	rows, err := ListAgentAuditEventsByDeployment("dep_T")
	if err != nil {
		t.Fatalf("query: %v", err)
	}
	if len(rows) != 2 || rows[0].EventID != "evt_early" {
		t.Fatalf("expected [evt_early, evt_late] order, got %+v", rows)
	}
}