package model

import (
	"encoding/json"
	"path/filepath"
	"testing"
	"time"

	"github.com/glebarez/sqlite"
	"gorm.io/gorm"
)

type legacyProxyRouteV7 struct {
	ID                 uint   `gorm:"primaryKey"`
	SiteName           string `gorm:"size:255;not null;default:''"`
	Domain             string `gorm:"uniqueIndex;size:255;not null"`
	Domains            string `gorm:"type:text;not null;default:'[]'"`
	OriginID           *uint  `gorm:"index"`
	OriginURL          string `gorm:"size:2048;not null"`
	OriginHost         string `gorm:"size:255"`
	Upstreams          string `gorm:"type:text;not null;default:'[]'"`
	Enabled            bool   `gorm:"not null;default:true"`
	EnableHTTPS        bool   `gorm:"column:enable_https;not null;default:false"`
	CertID             *uint
	CertIDs            string `gorm:"type:text;not null;default:'[]'"`
	RedirectHTTP       bool   `gorm:"not null;default:false"`
	LimitConnPerServer int    `gorm:"not null;default:0"`
	LimitConnPerIP     int    `gorm:"not null;default:0"`
	LimitRate          string `gorm:"size:32;not null;default:''"`
	CacheEnabled       bool   `gorm:"not null;default:false"`
	CachePolicy        string `gorm:"size:32;not null;default:''"`
	CacheRules         string `gorm:"type:text;not null;default:'[]'"`
	CustomHeaders      string `gorm:"type:text;not null;default:'[]'"`
	Remark             string `gorm:"size:255"`
	CreatedAt          time.Time
	UpdatedAt          time.Time
}

func (legacyProxyRouteV7) TableName() string {
	return "proxy_routes"
}

func openBareTestSQLiteDB(t *testing.T, name string) *gorm.DB {
	t.Helper()

	db, err := gorm.Open(sqlite.Open(filepath.Join(t.TempDir(), name)), &gorm.Config{})
	if err != nil {
		t.Fatalf("open sqlite db: %v", err)
	}
	sqlDB, err := db.DB()
	if err != nil {
		t.Fatalf("get sql db: %v", err)
	}
	t.Cleanup(func() {
		_ = sqlDB.Close()
	})
	return db
}

func openTestSQLiteDB(t *testing.T, name string) *gorm.DB {
	t.Helper()

	db := openBareTestSQLiteDB(t, name)
	if err := autoMigrateAll(db); err != nil {
		t.Fatalf("auto migrate db: %v", err)
	}
	return db
}

func findDBModelByTableName(t *testing.T, tableName string) dbModel {
	t.Helper()

	models, err := buildDBModels()
	if err != nil {
		t.Fatalf("build db models: %v", err)
	}
	for _, item := range models {
		if item.tableName == tableName {
			return item
		}
	}
	t.Fatalf("db model not found for table %s", tableName)
	return dbModel{}
}

func TestIsDatabaseEmpty(t *testing.T) {
	db := openTestSQLiteDB(t, "empty.db")

	empty, err := isDatabaseEmpty(db)
	if err != nil {
		t.Fatalf("isDatabaseEmpty returned error: %v", err)
	}
	if !empty {
		t.Fatal("expected database to be empty")
	}

	if err := db.Create(&User{
		Username:    "alice",
		Password:    "secret",
		DisplayName: "Alice",
		Role:        1,
		Status:      1,
	}).Error; err != nil {
		t.Fatalf("seed user: %v", err)
	}

	empty, err = isDatabaseEmpty(db)
	if err != nil {
		t.Fatalf("isDatabaseEmpty after seed returned error: %v", err)
	}
	if empty {
		t.Fatal("expected database to be non-empty")
	}
}

func TestMigrateTableDataCopiesRows(t *testing.T) {
	source := openTestSQLiteDB(t, "source.db")
	target := openTestSQLiteDB(t, "target.db")

	user := User{
		Id:          1,
		Username:    "root",
		Password:    "hashed",
		DisplayName: "Root User",
		Role:        100,
		Status:      1,
	}
	option := Option{
		Key:   "AgentHeartbeatInterval",
		Value: "10000",
	}

	if err := source.Create(&user).Error; err != nil {
		t.Fatalf("seed source user: %v", err)
	}
	if err := source.Create(&option).Error; err != nil {
		t.Fatalf("seed source option: %v", err)
	}

	if err := migrateTableData(source, target, findDBModelByTableName(t, "users")); err != nil {
		t.Fatalf("migrate users: %v", err)
	}
	if err := migrateTableData(source, target, findDBModelByTableName(t, "options")); err != nil {
		t.Fatalf("migrate options: %v", err)
	}

	var gotUser User
	if err := target.First(&gotUser, 1).Error; err != nil {
		t.Fatalf("query migrated user: %v", err)
	}
	if gotUser.Username != user.Username || gotUser.DisplayName != user.DisplayName {
		t.Fatalf("unexpected migrated user: %+v", gotUser)
	}

	var gotOption Option
	if err := target.First(&gotOption, "key = ?", option.Key).Error; err != nil {
		t.Fatalf("query migrated option: %v", err)
	}
	if gotOption.Value != option.Value {
		t.Fatalf("unexpected migrated option value: %s", gotOption.Value)
	}
}

func TestRegisterShardingAutoMigratesShardTables(t *testing.T) {
	db := openBareTestSQLiteDB(t, "sharded.db")
	if err := registerSharding(db, "sqlite"); err != nil {
		t.Fatalf("register sharding: %v", err)
	}
	if err := autoMigrateAll(db); err != nil {
		t.Fatalf("auto migrate db: %v", err)
	}

	for _, table := range []string{
		"node_metric_snapshots_00",
		"node_metric_snapshots_09",
		"node_request_reports_00",
		"node_request_reports_09",
		"node_access_logs_00",
		"node_access_logs_09",
	} {
		if !db.Migrator().HasTable(table) {
			t.Fatalf("expected sharded table %s to exist", table)
		}
	}
}

func TestMigrateObservabilityLegacyColumnsBackfillsHealthEventMetadata(t *testing.T) {
	db := openTestSQLiteDB(t, "legacy-health-events.db")

	if err := db.Exec("ALTER TABLE node_health_events ADD COLUMN raw_json TEXT").Error; err != nil {
		t.Fatalf("add raw_json column: %v", err)
	}
	rawJSON, err := json.Marshal(map[string]any{
		"event_type": "sync_error",
		"metadata": map[string]string{
			"reason": "checksum_mismatch",
			"scope":  "routes",
		},
	})
	if err != nil {
		t.Fatalf("marshal raw json: %v", err)
	}
	event := &NodeHealthEvent{
		NodeID:           "node-legacy",
		EventType:        "sync_error",
		Severity:         "warning",
		Status:           "active",
		Message:          "checksum mismatch",
		FirstTriggeredAt: time.Now().Add(-time.Minute),
		LastTriggeredAt:  time.Now(),
		ReportedAt:       time.Now(),
	}
	if err := db.Create(event).Error; err != nil {
		t.Fatalf("create health event: %v", err)
	}
	if err := db.Exec("UPDATE node_health_events SET raw_json = ? WHERE id = ?", string(rawJSON), event.ID).Error; err != nil {
		t.Fatalf("seed legacy raw_json: %v", err)
	}

	if err := migrateObservabilityLegacyColumns(db); err != nil {
		t.Fatalf("migrateObservabilityLegacyColumns: %v", err)
	}

	var got NodeHealthEvent
	if err := db.First(&got, event.ID).Error; err != nil {
		t.Fatalf("query health event: %v", err)
	}
	if got.MetadataJSON == "" {
		t.Fatal("expected metadata_json to be backfilled")
	}
}

func TestEnsureDatabaseSchemaUpToDateInitializesFreshDatabase(t *testing.T) {
	db := openBareTestSQLiteDB(t, "fresh-schema.db")
	if err := registerSharding(db, "sqlite"); err != nil {
		t.Fatalf("register sharding: %v", err)
	}

	if err := ensureDatabaseSchemaUpToDate(db, "sqlite"); err != nil {
		t.Fatalf("ensureDatabaseSchemaUpToDate: %v", err)
	}

	version, exists, err := loadDatabaseSchemaVersion(db)
	if err != nil {
		t.Fatalf("loadDatabaseSchemaVersion: %v", err)
	}
	if !exists {
		t.Fatal("expected database schema version to be recorded")
	}
	if version != currentDatabaseSchemaVersion {
		t.Fatalf("unexpected schema version: got %d want %d", version, currentDatabaseSchemaVersion)
	}
}

func TestEnsureDatabaseSchemaUpToDateUpgradesLegacyDatabase(t *testing.T) {
	db := openBareTestSQLiteDB(t, "legacy-schema.db")
	if err := registerSharding(db, "sqlite"); err != nil {
		t.Fatalf("register sharding: %v", err)
	}
	if err := autoMigrateAll(db); err != nil {
		t.Fatalf("auto migrate db: %v", err)
	}
	if err := db.Create(&User{
		Username:    "legacy",
		Password:    "secret",
		DisplayName: "Legacy User",
		Role:        1,
		Status:      1,
	}).Error; err != nil {
		t.Fatalf("seed legacy user: %v", err)
	}

	if err := ensureDatabaseSchemaUpToDate(db, "sqlite"); err != nil {
		t.Fatalf("ensureDatabaseSchemaUpToDate: %v", err)
	}

	version, exists, err := loadDatabaseSchemaVersion(db)
	if err != nil {
		t.Fatalf("loadDatabaseSchemaVersion: %v", err)
	}
	if !exists {
		t.Fatal("expected legacy database to gain a schema version record")
	}
	if version != currentDatabaseSchemaVersion {
		t.Fatalf("unexpected schema version: got %d want %d", version, currentDatabaseSchemaVersion)
	}
}

func TestMigrateOriginsSchemaBackfillsOrigins(t *testing.T) {
	db := openBareTestSQLiteDB(t, "legacy-origins.db")
	if err := registerSharding(db, "sqlite"); err != nil {
		t.Fatalf("register sharding: %v", err)
	}
	if err := applyCurrentSchema(db, "sqlite"); err != nil {
		t.Fatalf("applyCurrentSchema: %v", err)
	}
	now := time.Now().UTC()
	route := &ProxyRoute{
		Domain:    "app.example.com",
		OriginURL: "https://origin-a.internal:8443/api",
		Upstreams: `["https://origin-a.internal:8443/api"]`,
		Enabled:   true,
		CreatedAt: now,
		UpdatedAt: now,
	}
	if err := db.Create(route).Error; err != nil {
		t.Fatalf("seed proxy route: %v", err)
	}
	if err := db.Exec(`DELETE FROM origins`).Error; err != nil {
		t.Fatalf("clear origins: %v", err)
	}
	if err := db.Model(&ProxyRoute{}).Where("id = ?", route.ID).Update("origin_id", nil).Error; err != nil {
		t.Fatalf("clear route origin_id: %v", err)
	}

	if err := backfillOriginsFromProxyRoutes(db); err != nil {
		t.Fatalf("backfillOriginsFromProxyRoutes: %v", err)
	}

	if !db.Migrator().HasTable(&Origin{}) {
		t.Fatal("expected origins table to exist")
	}
	if !db.Migrator().HasColumn(&ProxyRoute{}, "origin_id") {
		t.Fatal("expected proxy_routes.origin_id column to exist")
	}

	reloadedRoute := &ProxyRoute{}
	if err := db.First(reloadedRoute, route.ID).Error; err != nil {
		t.Fatalf("query proxy route: %v", err)
	}
	if reloadedRoute.OriginID == nil || *reloadedRoute.OriginID == 0 {
		t.Fatal("expected migrated route to be linked to a backfilled origin")
	}

	origin := &Origin{}
	if err := db.First(origin, *reloadedRoute.OriginID).Error; err != nil {
		t.Fatalf("query origin: %v", err)
	}
	if origin.Address != "origin-a.internal" {
		t.Fatalf("unexpected backfilled origin address: %s", origin.Address)
	}
}

func TestEnsureDatabaseSchemaUpToDateAddsProxyRouteDomainCertificateFields(t *testing.T) {
	db := openBareTestSQLiteDB(t, "legacy-proxy-route-domain-cert-ids.db")
	if err := registerSharding(db, "sqlite"); err != nil {
		t.Fatalf("register sharding: %v", err)
	}
	if err := autoMigrateSchemaMetadata(db); err != nil {
		t.Fatalf("auto migrate schema metadata: %v", err)
	}

	for _, item := range registeredModels() {
		if _, ok := item.(*ProxyRoute); ok {
			continue
		}
		if err := db.AutoMigrate(item); err != nil {
			t.Fatalf("auto migrate supporting table: %v", err)
		}
	}
	if err := db.AutoMigrate(&legacyProxyRouteV7{}); err != nil {
		t.Fatalf("auto migrate legacy proxy_routes v7: %v", err)
	}

	now := time.Now().UTC()
	certID := uint(9)
	if err := db.Create(&legacyProxyRouteV7{
		SiteName:           "secure-site",
		Domain:             "secure.example.com",
		Domains:            `["secure.example.com","www.secure.example.com"]`,
		OriginURL:          "https://origin-secure.internal:8443",
		Upstreams:          `["https://origin-secure.internal:8443"]`,
		Enabled:            true,
		EnableHTTPS:        true,
		CertID:             &certID,
		CertIDs:            `[9]`,
		RedirectHTTP:       true,
		LimitConnPerServer: 120,
		LimitConnPerIP:     12,
		LimitRate:          "512k",
		CacheEnabled:       false,
		CachePolicy:        "",
		CacheRules:         `[]`,
		CustomHeaders:      `[]`,
		CreatedAt:          now,
		UpdatedAt:          now,
	}).Error; err != nil {
		t.Fatalf("seed legacy proxy route v7: %v", err)
	}
	if err := saveDatabaseSchemaVersion(db, 7); err != nil {
		t.Fatalf("save schema version: %v", err)
	}

	previousDB := DB
	DB = db
	t.Cleanup(func() {
		DB = previousDB
	})

	if err := ensureDatabaseSchemaUpToDate(db, "sqlite"); err != nil {
		t.Fatalf("ensureDatabaseSchemaUpToDate: %v", err)
	}

	var route ProxyRoute
	if err := db.First(&route).Error; err != nil {
		t.Fatalf("query migrated proxy route: %v", err)
	}

	var domainCertIDs []uint
	if err := json.Unmarshal([]byte(route.DomainCertIDs), &domainCertIDs); err != nil {
		t.Fatalf("decode migrated domain_cert_ids: %v", err)
	}
	if len(domainCertIDs) != 2 || domainCertIDs[0] != certID || domainCertIDs[1] != certID {
		t.Fatalf("unexpected migrated domain_cert_ids: %#v", domainCertIDs)
	}
}

func TestRunDatabaseSchemaMigrationDoesNotAdvanceVersionWhenValidationFails(t *testing.T) {
	db := openBareTestSQLiteDB(t, "failed-validation.db")

	err := runDatabaseSchemaMigration(db, "sqlite", databaseSchemaMigration{
		fromVersion: legacyDatabaseSchemaVersion,
		toVersion:   11,
		migrate: func(tx *gorm.DB, backend string) error {
			return autoMigrateSchemaMetadata(tx)
		},
		validate: func(tx *gorm.DB, backend string) error {
			return gorm.ErrInvalidDB
		},
	})
	if err == nil {
		t.Fatal("expected migration validation to fail")
	}

	_, exists, loadErr := loadDatabaseSchemaVersion(db)
	if loadErr != nil {
		t.Fatalf("loadDatabaseSchemaVersion: %v", loadErr)
	}
	if exists {
		t.Fatal("expected schema version to remain unset after failed validation")
	}
}

func TestEnsureDatabaseSchemaUpToDateAddsNodeIPManualOverride(t *testing.T) {
	db := openBareTestSQLiteDB(t, "node-ip-manual-override-migration.db")
	if err := registerSharding(db, "sqlite"); err != nil {
		t.Fatalf("register sharding: %v", err)
	}
	if err := applyCurrentSchema(db, "sqlite"); err != nil {
		t.Fatalf("apply current schema: %v", err)
	}
	if err := ensureDefaultWAFRuleGroup(db); err != nil {
		t.Fatalf("ensure default waf rule group: %v", err)
	}
	if err := db.Migrator().DropColumn(&Node{}, "ip_manual_override"); err != nil {
		t.Fatalf("drop ip_manual_override column: %v", err)
	}
	if db.Migrator().HasColumn(&Node{}, "ip_manual_override") {
		t.Fatal("expected test database to simulate schema v14 without ip_manual_override")
	}
	if err := saveDatabaseSchemaVersion(db, 14); err != nil {
		t.Fatalf("save schema version: %v", err)
	}

	if err := ensureDatabaseSchemaUpToDate(db, "sqlite"); err != nil {
		t.Fatalf("ensureDatabaseSchemaUpToDate: %v", err)
	}

	if !db.Migrator().HasColumn(&Node{}, "ip_manual_override") {
		t.Fatal("expected migration to add nodes.ip_manual_override")
	}
	version, exists, err := loadDatabaseSchemaVersion(db)
	if err != nil {
		t.Fatalf("loadDatabaseSchemaVersion: %v", err)
	}
	if !exists {
		t.Fatal("expected schema version record to exist")
	}
	if version != currentDatabaseSchemaVersion {
		t.Fatalf("unexpected schema version: got %d want %d", version, currentDatabaseSchemaVersion)
	}
}