package storage

import (
	"context"
	"database/sql"
	"errors"
	"fmt"
	"log"
	"os"
	"path/filepath"
	"strings"
	"sync"
	"time"

	_ "modernc.org/sqlite"
)

// =========================================================================
//  Database Connection
// =========================================================================

var (
	db          *sql.DB
	initOnce    sync.Once
	initErr     error
	defaultPath = "fail2ban-ui.db"
)

// =========================================================================
//  Conversion Helpers
// =========================================================================

func boolToInt(b bool) int {
	if b {
		return 1
	}
	return 0
}

func intToBool(i int) bool {
	return i != 0
}

func stringFromNull(ns sql.NullString) string {
	if ns.Valid {
		return ns.String
	}
	return ""
}

func intFromNull(ni sql.NullInt64) int {
	if ni.Valid {
		return int(ni.Int64)
	}
	return 0
}

// =========================================================================
//  Types
// =========================================================================

type AppSettingsRecord struct {
	Language               string
	Port                   int
	Debug                  bool
	RestartNeeded          bool
	CallbackURL            string
	CallbackSecret         string
	AlertCountriesJSON     string
	EmailAlertsForBans     bool
	EmailAlertsForUnbans   bool
	ConsoleOutput          bool
	SMTPHost               string
	SMTPPort               int
	SMTPUsername           string
	SMTPPassword           string
	SMTPFrom               string
	SMTPUseTLS             bool
	SMTPInsecureSkipVerify bool
	SMTPAuthMethod         string
	BantimeIncrement       bool
	DefaultJailEnable      bool
	IgnoreIP               string
	Bantime                string
	Findtime               string
	MaxRetry               int
	DestEmail              string
	Banaction              string
	BanactionAllports      string
	Chain                  string
	BantimeRndtime         string
	AdvancedActionsJSON    string
	GeoIPProvider          string
	GeoIPDatabasePath      string
	MaxLogLines            int
}

type ServerRecord struct {
	ID           string
	Name         string
	Type         string
	Host         string
	Port         int
	SocketPath   string
	LogPath      string
	SSHUser      string
	SSHKeyPath   string
	AgentURL     string
	AgentSecret  string
	Hostname     string
	TagsJSON     string
	IsDefault    bool
	Enabled      bool
	NeedsRestart bool
	CreatedAt    time.Time
	UpdatedAt    time.Time
}

type BanEventRecord struct {
	ID         int64     `json:"id"`
	ServerID   string    `json:"serverId"`
	ServerName string    `json:"serverName"`
	Jail       string    `json:"jail"`
	IP         string    `json:"ip"`
	Country    string    `json:"country"`
	Hostname   string    `json:"hostname"`
	Failures   string    `json:"failures"`
	Whois      string    `json:"whois"`
	Logs       string    `json:"logs"`
	EventType  string    `json:"eventType"`
	OccurredAt time.Time `json:"occurredAt"`
	CreatedAt  time.Time `json:"createdAt"`
}

type RecurringIPStat struct {
	IP       string    `json:"ip"`
	Country  string    `json:"country"`
	Count    int64     `json:"count"`
	LastSeen time.Time `json:"lastSeen"`
}

type PermanentBlockRecord struct {
	ID          int64     `json:"id"`
	IP          string    `json:"ip"`
	Integration string    `json:"integration"`
	Status      string    `json:"status"`
	Details     string    `json:"details"`
	Message     string    `json:"message"`
	ServerID    string    `json:"serverId"`
	CreatedAt   time.Time `json:"createdAt"`
	UpdatedAt   time.Time `json:"updatedAt"`
}

// Initialize the database.
func Init(dbPath string) error {
	initOnce.Do(func() {
		if dbPath == "" {
			dbPath = defaultPath
		}
		if err := ensureDirectory(dbPath); err != nil {
			initErr = err
			return
		}

		if err := ensureSSHDirectory(); err != nil {
			log.Printf("Warning: failed to ensure .ssh directory: %v", err)
		}

		var err error
		db, err = sql.Open("sqlite", fmt.Sprintf("file:%s?_pragma=journal_mode(WAL)&_pragma=busy_timeout=5000", dbPath))
		if err != nil {
			initErr = err
			return
		}

		if err = db.Ping(); err != nil {
			initErr = err
			return
		}

		initErr = ensureSchema(context.Background())
	})
	return initErr
}

// Close the database.
func Close() error {
	if db == nil {
		return nil
	}
	return db.Close()
}

// Get the app settings.
func GetAppSettings(ctx context.Context) (AppSettingsRecord, bool, error) {
	if db == nil {
		return AppSettingsRecord{}, false, errors.New("storage not initialised")
	}

	row := db.QueryRowContext(ctx, `
SELECT language, port, debug, restart_needed, callback_url, callback_secret, alert_countries, email_alerts_for_bans, email_alerts_for_unbans, smtp_host, smtp_port, smtp_username, smtp_password, smtp_from, smtp_use_tls, bantime_increment, default_jail_enable, ignore_ip, bantime, findtime, maxretry, destemail, banaction, banaction_allports, advanced_actions, geoip_provider, geoip_database_path, max_log_lines, console_output, smtp_insecure_skip_verify, smtp_auth_method, chain, bantime_rndtime
FROM app_settings
WHERE id = 1`)

	var (
		lang, callback, callbackSecret, alerts, smtpHost, smtpUser, smtpPass, smtpFrom, ignoreIP, bantime, findtime, destemail, banaction, banactionAllports, chain, bantimeRndtime, advancedActions, geoipProvider, geoipDatabasePath, smtpAuthMethod sql.NullString
		port, smtpPort, maxretry, maxLogLines                                                                                                                                                                                                          sql.NullInt64
		debug, restartNeeded, smtpTLS, bantimeInc, defaultJailEn, emailAlertsForBans, emailAlertsForUnbans, consoleOutput, smtpInsecureSkipVerify                                                                                                      sql.NullInt64
	)

	err := row.Scan(&lang, &port, &debug, &restartNeeded, &callback, &callbackSecret, &alerts, &emailAlertsForBans, &emailAlertsForUnbans, &smtpHost, &smtpPort, &smtpUser, &smtpPass, &smtpFrom, &smtpTLS, &bantimeInc, &defaultJailEn, &ignoreIP, &bantime, &findtime, &maxretry, &destemail, &banaction, &banactionAllports, &advancedActions, &geoipProvider, &geoipDatabasePath, &maxLogLines, &consoleOutput, &smtpInsecureSkipVerify, &smtpAuthMethod, &chain, &bantimeRndtime)
	if errors.Is(err, sql.ErrNoRows) {
		return AppSettingsRecord{}, false, nil
	}
	if err != nil {
		return AppSettingsRecord{}, false, err
	}

	rec := AppSettingsRecord{
		Language:               stringFromNull(lang),
		Port:                   intFromNull(port),
		Debug:                  intToBool(intFromNull(debug)),
		RestartNeeded:          intToBool(intFromNull(restartNeeded)),
		CallbackURL:            stringFromNull(callback),
		CallbackSecret:         stringFromNull(callbackSecret),
		AlertCountriesJSON:     stringFromNull(alerts),
		EmailAlertsForBans:     intToBool(intFromNull(emailAlertsForBans)),
		EmailAlertsForUnbans:   intToBool(intFromNull(emailAlertsForUnbans)),
		SMTPHost:               stringFromNull(smtpHost),
		SMTPPort:               intFromNull(smtpPort),
		SMTPUsername:           stringFromNull(smtpUser),
		SMTPPassword:           stringFromNull(smtpPass),
		SMTPFrom:               stringFromNull(smtpFrom),
		SMTPUseTLS:             intToBool(intFromNull(smtpTLS)),
		SMTPInsecureSkipVerify: intToBool(intFromNull(smtpInsecureSkipVerify)),
		SMTPAuthMethod:         stringFromNull(smtpAuthMethod),
		BantimeIncrement:       intToBool(intFromNull(bantimeInc)),
		DefaultJailEnable:      intToBool(intFromNull(defaultJailEn)),
		IgnoreIP:               stringFromNull(ignoreIP),
		Bantime:                stringFromNull(bantime),
		Findtime:               stringFromNull(findtime),
		MaxRetry:               intFromNull(maxretry),
		DestEmail:              stringFromNull(destemail),
		Banaction:              stringFromNull(banaction),
		BanactionAllports:      stringFromNull(banactionAllports),
		Chain:                  stringFromNull(chain),
		BantimeRndtime:         stringFromNull(bantimeRndtime),
		AdvancedActionsJSON:    stringFromNull(advancedActions),
		GeoIPProvider:          stringFromNull(geoipProvider),
		GeoIPDatabasePath:      stringFromNull(geoipDatabasePath),
		MaxLogLines:            intFromNull(maxLogLines),
		ConsoleOutput:          intToBool(intFromNull(consoleOutput)),
	}

	return rec, true, nil
}

func SaveAppSettings(ctx context.Context, rec AppSettingsRecord) error {
	if db == nil {
		return errors.New("storage not initialised")
	}
	_, err := db.ExecContext(ctx, `
INSERT INTO app_settings (
	id, language, port, debug, restart_needed, callback_url, callback_secret, alert_countries, email_alerts_for_bans, email_alerts_for_unbans, smtp_host, smtp_port, smtp_username, smtp_password, smtp_from, smtp_use_tls, bantime_increment, default_jail_enable, ignore_ip, bantime, findtime, maxretry, destemail, banaction, banaction_allports, advanced_actions, geoip_provider, geoip_database_path, max_log_lines, console_output, smtp_insecure_skip_verify, smtp_auth_method, chain, bantime_rndtime
) VALUES (
	1, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?
) ON CONFLICT(id) DO UPDATE SET
	language = excluded.language,
	port = excluded.port,
	debug = excluded.debug,
	restart_needed = excluded.restart_needed,
	callback_url = excluded.callback_url,
	callback_secret = excluded.callback_secret,
	alert_countries = excluded.alert_countries,
	email_alerts_for_bans = excluded.email_alerts_for_bans,
	email_alerts_for_unbans = excluded.email_alerts_for_unbans,
	smtp_host = excluded.smtp_host,
	smtp_port = excluded.smtp_port,
	smtp_username = excluded.smtp_username,
	smtp_password = excluded.smtp_password,
	smtp_from = excluded.smtp_from,
	smtp_use_tls = excluded.smtp_use_tls,
	bantime_increment = excluded.bantime_increment,
	default_jail_enable = excluded.default_jail_enable,
	ignore_ip = excluded.ignore_ip,
	bantime = excluded.bantime,
	findtime = excluded.findtime,
	maxretry = excluded.maxretry,
	destemail = excluded.destemail,
	banaction = excluded.banaction,
	banaction_allports = excluded.banaction_allports,
	advanced_actions = excluded.advanced_actions,
	geoip_provider = excluded.geoip_provider,
	geoip_database_path = excluded.geoip_database_path,
	max_log_lines = excluded.max_log_lines,
	console_output = excluded.console_output,
	smtp_insecure_skip_verify = excluded.smtp_insecure_skip_verify,
	smtp_auth_method = excluded.smtp_auth_method,
	chain = excluded.chain,
	bantime_rndtime = excluded.bantime_rndtime
`, rec.Language,
		rec.Port,
		boolToInt(rec.Debug),
		boolToInt(rec.RestartNeeded),
		rec.CallbackURL,
		rec.CallbackSecret,
		rec.AlertCountriesJSON,
		boolToInt(rec.EmailAlertsForBans),
		boolToInt(rec.EmailAlertsForUnbans),
		rec.SMTPHost,
		rec.SMTPPort,
		rec.SMTPUsername,
		rec.SMTPPassword,
		rec.SMTPFrom,
		boolToInt(rec.SMTPUseTLS),
		boolToInt(rec.BantimeIncrement),
		boolToInt(rec.DefaultJailEnable),
		rec.IgnoreIP,
		rec.Bantime,
		rec.Findtime,
		rec.MaxRetry,
		rec.DestEmail,
		rec.Banaction,
		rec.BanactionAllports,
		rec.AdvancedActionsJSON,
		rec.GeoIPProvider,
		rec.GeoIPDatabasePath,
		rec.MaxLogLines,
		boolToInt(rec.ConsoleOutput),
		boolToInt(rec.SMTPInsecureSkipVerify),
		rec.SMTPAuthMethod,
		rec.Chain,
		rec.BantimeRndtime)
	return err
}

// =========================================================================
//  Servers
// =========================================================================

func ListServers(ctx context.Context) ([]ServerRecord, error) {
	if db == nil {
		return nil, errors.New("storage not initialised")
	}

	rows, err := db.QueryContext(ctx, `
SELECT id, name, type, host, port, socket_path, log_path, ssh_user, ssh_key_path, agent_url, agent_secret, hostname, tags, is_default, enabled, needs_restart, created_at, updated_at
FROM servers
ORDER BY created_at`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var records []ServerRecord
	for rows.Next() {
		var rec ServerRecord
		var host, socket, logPath, sshUser, sshKey, agentURL, agentSecret, hostname, tags sql.NullString
		var name, serverType sql.NullString
		var created, updated sql.NullString
		var port sql.NullInt64
		var isDefault, enabled, needsRestart sql.NullInt64

		if err := rows.Scan(
			&rec.ID,
			&name,
			&serverType,
			&host,
			&port,
			&socket,
			&logPath,
			&sshUser,
			&sshKey,
			&agentURL,
			&agentSecret,
			&hostname,
			&tags,
			&isDefault,
			&enabled,
			&needsRestart,
			&created,
			&updated,
		); err != nil {
			return nil, err
		}

		rec.Name = stringFromNull(name)
		rec.Type = stringFromNull(serverType)
		rec.Host = stringFromNull(host)
		rec.Port = intFromNull(port)
		rec.SocketPath = stringFromNull(socket)
		rec.LogPath = stringFromNull(logPath)
		rec.SSHUser = stringFromNull(sshUser)
		rec.SSHKeyPath = stringFromNull(sshKey)
		rec.AgentURL = stringFromNull(agentURL)
		rec.AgentSecret = stringFromNull(agentSecret)
		rec.Hostname = stringFromNull(hostname)
		rec.TagsJSON = stringFromNull(tags)
		rec.IsDefault = intToBool(intFromNull(isDefault))
		rec.Enabled = intToBool(intFromNull(enabled))
		rec.NeedsRestart = intToBool(intFromNull(needsRestart))

		if created.Valid {
			if t, err := time.Parse(time.RFC3339Nano, created.String); err == nil {
				rec.CreatedAt = t
			}
		}
		if updated.Valid {
			if t, err := time.Parse(time.RFC3339Nano, updated.String); err == nil {
				rec.UpdatedAt = t
			}
		}

		records = append(records, rec)
	}

	return records, rows.Err()
}

func ReplaceServers(ctx context.Context, servers []ServerRecord) error {
	if db == nil {
		return errors.New("storage not initialised")
	}

	tx, err := db.BeginTx(ctx, nil)
	if err != nil {
		return err
	}
	defer func() {
		if err != nil {
			_ = tx.Rollback()
		}
	}()

	if _, err = tx.ExecContext(ctx, `DELETE FROM servers`); err != nil {
		return err
	}

	stmt, err := tx.PrepareContext(ctx, `
INSERT INTO servers (
	id, name, type, host, port, socket_path, log_path, ssh_user, ssh_key_path, agent_url, agent_secret, hostname, tags, is_default, enabled, needs_restart, created_at, updated_at
) VALUES (
	?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?
)`)
	if err != nil {
		return err
	}
	defer stmt.Close()

	for _, srv := range servers {
		createdAt := srv.CreatedAt
		if createdAt.IsZero() {
			createdAt = time.Now().UTC()
		}
		updatedAt := srv.UpdatedAt
		if updatedAt.IsZero() {
			updatedAt = createdAt
		}
		if _, err = stmt.ExecContext(ctx,
			srv.ID,
			srv.Name,
			srv.Type,
			srv.Host,
			srv.Port,
			srv.SocketPath,
			srv.LogPath,
			srv.SSHUser,
			srv.SSHKeyPath,
			srv.AgentURL,
			srv.AgentSecret,
			srv.Hostname,
			srv.TagsJSON,
			boolToInt(srv.IsDefault),
			boolToInt(srv.Enabled),
			boolToInt(srv.NeedsRestart),
			createdAt.Format(time.RFC3339Nano),
			updatedAt.Format(time.RFC3339Nano),
		); err != nil {
			return err
		}
	}

	err = tx.Commit()
	return err
}

func DeleteServer(ctx context.Context, id string) error {
	if db == nil {
		return errors.New("storage not initialised")
	}
	_, err := db.ExecContext(ctx, `DELETE FROM servers WHERE id = ?`, id)
	return err
}

// =========================================================================
//  Ban Events Records
// =========================================================================

// Stores a ban/unban event into the database.
func RecordBanEvent(ctx context.Context, record BanEventRecord) error {
	if db == nil {
		return errors.New("storage not initialised")
	}

	if record.ServerID == "" {
		return errors.New("server id is required")
	}
	now := time.Now().UTC()
	if record.CreatedAt.IsZero() {
		record.CreatedAt = now
	}
	if record.OccurredAt.IsZero() {
		record.OccurredAt = now
	}
	// If the event type is not set, we set it to "ban" by default.
	eventType := record.EventType
	if eventType == "" {
		eventType = "ban"
	}

	const query = `
INSERT INTO ban_events (
	server_id, server_name, jail, ip, country, hostname, failures, whois, logs, event_type, occurred_at, created_at
) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`

	_, err := db.ExecContext(
		ctx,
		query,
		record.ServerID,
		record.ServerName,
		record.Jail,
		record.IP,
		record.Country,
		record.Hostname,
		record.Failures,
		record.Whois,
		record.Logs,
		eventType,
		record.OccurredAt.UTC(),
		record.CreatedAt.UTC(),
	)
	if err != nil {
		return err
	}

	return nil
}

// Returns ban events ordered by creation date descending.
func ListBanEvents(ctx context.Context, serverID string, limit int, since time.Time) ([]BanEventRecord, error) {
	if db == nil {
		return nil, errors.New("storage not initialised")
	}

	if limit <= 0 || limit > 500 {
		limit = 100
	}

	baseQuery := `
SELECT id, server_id, server_name, jail, ip, country, hostname, failures, whois, logs, event_type, occurred_at, created_at
FROM ban_events
WHERE 1=1`

	args := []any{}
	if serverID != "" {
		baseQuery += " AND server_id = ?"
		args = append(args, serverID)
	}
	if !since.IsZero() {
		baseQuery += " AND occurred_at >= ?"
		args = append(args, since.UTC())
	}

	baseQuery += " ORDER BY occurred_at DESC LIMIT ?"
	args = append(args, limit)

	rows, err := db.QueryContext(ctx, baseQuery, args...)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var results []BanEventRecord
	for rows.Next() {
		var rec BanEventRecord
		var eventType sql.NullString
		if err := rows.Scan(
			&rec.ID,
			&rec.ServerID,
			&rec.ServerName,
			&rec.Jail,
			&rec.IP,
			&rec.Country,
			&rec.Hostname,
			&rec.Failures,
			&rec.Whois,
			&rec.Logs,
			&eventType,
			&rec.OccurredAt,
			&rec.CreatedAt,
		); err != nil {
			return nil, err
		}
		if eventType.Valid {
			rec.EventType = eventType.String
		} else {
			rec.EventType = "ban"
		}
		results = append(results, rec)
	}

	return results, rows.Err()
}

const (
	// MaxBanEventsLimit is the maximum number of events per API request (pagination page size).
	MaxBanEventsLimit = 50
	// MaxBanEventsOffset is the maximum offset (total events loaded in UI capped for browser stability).
	MaxBanEventsOffset = 1000
)

// Returns ban events with optional search and country filter, ordered by occurred_at DESC.
// search is applied as LIKE %search% on ip, jail, server_name, hostname, country.
// limit is capped at MaxBanEventsLimit; offset is capped at MaxBanEventsOffset.
func ListBanEventsFiltered(ctx context.Context, serverID string, limit, offset int, since time.Time, search, country string) ([]BanEventRecord, error) {
	if db == nil {
		return nil, errors.New("storage not initialised")
	}
	if limit <= 0 || limit > MaxBanEventsLimit {
		limit = MaxBanEventsLimit
	}
	if offset < 0 || offset > MaxBanEventsOffset {
		offset = 0
	}

	baseQuery := `
SELECT id, server_id, server_name, jail, ip, country, hostname, failures, whois, logs, event_type, occurred_at, created_at
FROM ban_events
WHERE 1=1`
	args := []any{}

	if serverID != "" {
		baseQuery += " AND server_id = ?"
		args = append(args, serverID)
	}
	if !since.IsZero() {
		baseQuery += " AND occurred_at >= ?"
		args = append(args, since.UTC())
	}
	search = strings.TrimSpace(search)
	if search != "" {
		baseQuery += " AND (ip LIKE ? OR jail LIKE ? OR server_name LIKE ? OR COALESCE(hostname,'') LIKE ? OR COALESCE(country,'') LIKE ?)"
		pattern := "%" + search + "%"
		for i := 0; i < 5; i++ {
			args = append(args, pattern)
		}
	}
	if country != "" && country != "all" {
		if country == "__unknown__" {
			baseQuery += " AND (country IS NULL OR country = '')"
		} else {
			baseQuery += " AND LOWER(COALESCE(country,'')) = ?"
			args = append(args, strings.ToLower(country))
		}
	}

	baseQuery += " ORDER BY occurred_at DESC LIMIT ? OFFSET ?"
	args = append(args, limit, offset)

	rows, err := db.QueryContext(ctx, baseQuery, args...)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var results []BanEventRecord
	for rows.Next() {
		var rec BanEventRecord
		var eventType sql.NullString
		if err := rows.Scan(
			&rec.ID,
			&rec.ServerID,
			&rec.ServerName,
			&rec.Jail,
			&rec.IP,
			&rec.Country,
			&rec.Hostname,
			&rec.Failures,
			&rec.Whois,
			&rec.Logs,
			&eventType,
			&rec.OccurredAt,
			&rec.CreatedAt,
		); err != nil {
			return nil, err
		}
		if eventType.Valid {
			rec.EventType = eventType.String
		} else {
			rec.EventType = "ban"
		}
		results = append(results, rec)
	}
	return results, rows.Err()
}

// Returns the total count of ban events matching the same filters as ListBanEventsFiltered.
func CountBanEventsFiltered(ctx context.Context, serverID string, since time.Time, search, country string) (int64, error) {
	if db == nil {
		return 0, errors.New("storage not initialised")
	}

	query := `SELECT COUNT(*) FROM ban_events WHERE 1=1`
	args := []any{}

	if serverID != "" {
		query += " AND server_id = ?"
		args = append(args, serverID)
	}
	if !since.IsZero() {
		query += " AND occurred_at >= ?"
		args = append(args, since.UTC())
	}
	search = strings.TrimSpace(search)
	if search != "" {
		query += " AND (ip LIKE ? OR jail LIKE ? OR server_name LIKE ? OR COALESCE(hostname,'') LIKE ? OR COALESCE(country,'') LIKE ?)"
		pattern := "%" + search + "%"
		for i := 0; i < 5; i++ {
			args = append(args, pattern)
		}
	}
	if country != "" && country != "all" {
		if country == "__unknown__" {
			query += " AND (country IS NULL OR country = '')"
		} else {
			query += " AND LOWER(COALESCE(country,'')) = ?"
			args = append(args, strings.ToLower(country))
		}
	}

	var total int64
	if err := db.QueryRowContext(ctx, query, args...).Scan(&total); err != nil {
		return 0, err
	}
	return total, nil
}

// Returns simple aggregation per server.
func CountBanEventsByServer(ctx context.Context, since time.Time) (map[string]int64, error) {
	if db == nil {
		return nil, errors.New("storage not initialised")
	}

	query := `
SELECT server_id, COUNT(*) 
FROM ban_events
WHERE 1=1`
	args := []any{}

	if !since.IsZero() {
		query += " AND occurred_at >= ?"
		args = append(args, since.UTC())
	}

	query += " GROUP BY server_id"

	rows, err := db.QueryContext(ctx, query, args...)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	result := make(map[string]int64)
	for rows.Next() {
		var serverID string
		var count int64
		if err := rows.Scan(&serverID, &count); err != nil {
			return nil, err
		}
		result[serverID] = count
	}

	return result, rows.Err()
}

// Returns total number of ban events optionally filtered by time and server.
func CountBanEvents(ctx context.Context, since time.Time, serverID string) (int64, error) {
	if db == nil {
		return 0, errors.New("storage not initialised")
	}

	query := `
SELECT COUNT(*)
FROM ban_events
WHERE 1=1`
	args := []any{}

	if serverID != "" {
		query += " AND server_id = ?"
		args = append(args, serverID)
	}

	if !since.IsZero() {
		query += " AND occurred_at >= ?"
		args = append(args, since.UTC())
	}

	var total int64
	if err := db.QueryRowContext(ctx, query, args...).Scan(&total); err != nil {
		return 0, err
	}
	return total, nil
}

// Returns total number of ban events for a specific IP and optional server.
func CountBanEventsByIP(ctx context.Context, ip, serverID string) (int64, error) {
	if db == nil {
		return 0, errors.New("storage not initialised")
	}
	if ip == "" {
		return 0, errors.New("ip is required")
	}

	query := `
SELECT COUNT(*)
FROM ban_events
WHERE ip = ? AND (event_type = 'ban' OR event_type IS NULL)`
	args := []any{ip}

	if serverID != "" {
		query += " AND server_id = ?"
		args = append(args, serverID)
	}

	var total int64
	if err := db.QueryRowContext(ctx, query, args...).Scan(&total); err != nil {
		return 0, err
	}
	return total, nil
}

// Returns aggregation per country code, optionally filtered by server.
func CountBanEventsByCountry(ctx context.Context, since time.Time, serverID string) (map[string]int64, error) {
	if db == nil {
		return nil, errors.New("storage not initialised")
	}

	query := `
SELECT COALESCE(country, '') AS country, COUNT(*)
FROM ban_events
WHERE 1=1`
	args := []any{}

	if serverID != "" {
		query += " AND server_id = ?"
		args = append(args, serverID)
	}

	if !since.IsZero() {
		query += " AND occurred_at >= ?"
		args = append(args, since.UTC())
	}

	query += " GROUP BY COALESCE(country, '')"

	rows, err := db.QueryContext(ctx, query, args...)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	result := make(map[string]int64)
	for rows.Next() {
		var country sql.NullString
		var count int64
		if err := rows.Scan(&country, &count); err != nil {
			return nil, err
		}
		result[stringFromNull(country)] = count
	}

	return result, rows.Err()
}

// =========================================================================
//  Recurring IP Statistics
// =========================================================================

// Returns IPs that have been banned at least minCount times, optionally filtered by server.
func ListRecurringIPStats(ctx context.Context, since time.Time, minCount, limit int, serverID string) ([]RecurringIPStat, error) {
	if db == nil {
		return nil, errors.New("storage not initialised")
	}

	if minCount < 2 {
		minCount = 2
	}
	if limit <= 0 || limit > 500 {
		limit = 100
	}

	query := `
SELECT ip, COALESCE(country, '') AS country, COUNT(*) AS cnt, MAX(occurred_at) AS last_seen
FROM ban_events
WHERE ip != '' AND (event_type = 'ban' OR event_type IS NULL)`
	args := []any{}

	if serverID != "" {
		query += " AND server_id = ?"
		args = append(args, serverID)
	}

	if !since.IsZero() {
		query += " AND occurred_at >= ?"
		args = append(args, since.UTC())
	}

	query += `
GROUP BY ip, COALESCE(country, '')
HAVING cnt >= ?
ORDER BY cnt DESC, last_seen DESC
LIMIT ?`

	args = append(args, minCount, limit)

	rows, err := db.QueryContext(ctx, query, args...)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var results []RecurringIPStat
	for rows.Next() {
		var stat RecurringIPStat
		var lastSeenStr sql.NullString
		if err := rows.Scan(&stat.IP, &stat.Country, &stat.Count, &lastSeenStr); err != nil {
			return nil, fmt.Errorf("failed to scan row: %w", err)
		}

		if lastSeenStr.Valid && lastSeenStr.String != "" {
			formats := []string{
				"2006-01-02 15:04:05.999999999 -0700 MST",
				time.RFC3339Nano,
				time.RFC3339,
				"2006-01-02 15:04:05.999999999+00:00",
				"2006-01-02 15:04:05+00:00",
				"2006-01-02 15:04:05.999999999",
				"2006-01-02 15:04:05",
				"2006-01-02T15:04:05.999999999Z",
				"2006-01-02T15:04:05Z",
				"2006-01-02T15:04:05.999999999",
				"2006-01-02T15:04:05",
			}
			parsed := time.Time{}
			for _, format := range formats {
				if t, parseErr := time.Parse(format, lastSeenStr.String); parseErr == nil {
					parsed = t.UTC()
					break
				}
			}
			if parsed.IsZero() {
				log.Printf("ERROR: Could not parse lastSeen datetime '%s' (length: %d) for IP %s. All format attempts failed.", lastSeenStr.String, len(lastSeenStr.String), stat.IP)
			}
			stat.LastSeen = parsed
		} else {
			log.Printf("WARNING: lastSeen is NULL or empty for IP %s", stat.IP)
		}
		results = append(results, stat)
	}

	return results, rows.Err()
}

// =========================================================================
//  Schema Management
// =========================================================================

func ensureSchema(ctx context.Context) error {
	if db == nil {
		return errors.New("storage not initialised")
	}

	const createTable = `
CREATE TABLE IF NOT EXISTS app_settings (
	id INTEGER PRIMARY KEY CHECK (id = 1),
	-- Basic app settings
	language TEXT,
	port INTEGER,
	debug INTEGER,
	restart_needed INTEGER,
	-- Callback settings
	callback_url TEXT,
	callback_secret TEXT,
	-- Alert settings
	alert_countries TEXT,
	email_alerts_for_bans INTEGER DEFAULT 1,
	email_alerts_for_unbans INTEGER DEFAULT 0,
	-- SMTP settings
	smtp_host TEXT,
	smtp_port INTEGER,
	smtp_username TEXT,
	smtp_password TEXT,
	smtp_from TEXT,
	smtp_use_tls INTEGER,
	-- Fail2Ban DEFAULT settings
	bantime_increment INTEGER,
	default_jail_enable INTEGER,
	ignore_ip TEXT,
	bantime TEXT,
	findtime TEXT,
	maxretry INTEGER,
	destemail TEXT,
	banaction TEXT,
	banaction_allports TEXT,
	-- Advanced features
	advanced_actions TEXT,
	geoip_provider TEXT,
	geoip_database_path TEXT,
	max_log_lines INTEGER,
	-- Console output settings
	console_output INTEGER DEFAULT 0
);

CREATE TABLE IF NOT EXISTS servers (
	id TEXT PRIMARY KEY,
	name TEXT,
	type TEXT,
	host TEXT,
	port INTEGER,
	socket_path TEXT,
	log_path TEXT,
	ssh_user TEXT,
	ssh_key_path TEXT,
	agent_url TEXT,
	agent_secret TEXT,
	hostname TEXT,
	tags TEXT,
	is_default INTEGER,
	enabled INTEGER,
	needs_restart INTEGER DEFAULT 0,
	created_at TEXT,
	updated_at TEXT
);

CREATE TABLE IF NOT EXISTS ban_events (
	id INTEGER PRIMARY KEY AUTOINCREMENT,
	server_id TEXT NOT NULL,
	server_name TEXT NOT NULL,
	jail TEXT NOT NULL,
	ip TEXT NOT NULL,
	country TEXT,
	hostname TEXT,
	failures TEXT,
	whois TEXT,
	logs TEXT,
	event_type TEXT NOT NULL DEFAULT 'ban',
	occurred_at DATETIME NOT NULL,
	created_at DATETIME NOT NULL
);

CREATE INDEX IF NOT EXISTS idx_ban_events_server_id ON ban_events(server_id);
CREATE INDEX IF NOT EXISTS idx_ban_events_occurred_at ON ban_events(occurred_at);
CREATE INDEX IF NOT EXISTS idx_ban_events_ip ON ban_events(ip);

CREATE TABLE IF NOT EXISTS permanent_blocks (
	id INTEGER PRIMARY KEY AUTOINCREMENT,
	ip TEXT NOT NULL,
	integration TEXT NOT NULL,
	status TEXT NOT NULL,
	details TEXT,
	message TEXT,
	server_id TEXT,
	created_at TEXT NOT NULL,
	updated_at TEXT NOT NULL,
	UNIQUE(ip, integration)
);

CREATE INDEX IF NOT EXISTS idx_perm_blocks_status ON permanent_blocks(status);
`

	if _, err := db.ExecContext(ctx, createTable); err != nil {
		return err
	}
	if _, err := db.ExecContext(ctx, `ALTER TABLE app_settings ADD COLUMN console_output INTEGER DEFAULT 0`); err != nil {
		if err != nil && !strings.Contains(strings.ToLower(err.Error()), "duplicate column name") {
			return err
		}
	}
	if _, err := db.ExecContext(ctx, `ALTER TABLE app_settings ADD COLUMN smtp_insecure_skip_verify INTEGER DEFAULT 0`); err != nil {
		if err != nil && !strings.Contains(strings.ToLower(err.Error()), "duplicate column name") {
			return err
		}
	}
	if _, err := db.ExecContext(ctx, `ALTER TABLE app_settings ADD COLUMN smtp_auth_method TEXT DEFAULT 'auto'`); err != nil {
		if err != nil && !strings.Contains(strings.ToLower(err.Error()), "duplicate column name") {
			return err
		}
	}
	if _, err := db.ExecContext(ctx, `ALTER TABLE app_settings ADD COLUMN chain TEXT DEFAULT 'INPUT'`); err != nil {
		if err != nil && !strings.Contains(strings.ToLower(err.Error()), "duplicate column name") {
			return err
		}
	}
	if _, err := db.ExecContext(ctx, `ALTER TABLE app_settings ADD COLUMN bantime_rndtime TEXT DEFAULT ''`); err != nil {
		if err != nil && !strings.Contains(strings.ToLower(err.Error()), "duplicate column name") {
			return err
		}
	}
	return nil
}

func ensureDirectory(path string) error {
	if path == ":memory:" {
		return nil
	}
	dir := filepath.Dir(path)
	if dir == "." || dir == "" {
		return nil
	}
	return os.MkdirAll(dir, 0o755)
}

// Ensures .ssh exists for SSH key storage (/config/.ssh in container, ~/.ssh on host).
func ensureSSHDirectory() error {
	var sshDir string
	if _, container := os.LookupEnv("CONTAINER"); container {
		sshDir = "/config/.ssh"
	} else {
		home, err := os.UserHomeDir()
		if err != nil {
			return fmt.Errorf("failed to get user home directory: %w", err)
		}
		sshDir = filepath.Join(home, ".ssh")
	}

	if err := os.MkdirAll(sshDir, 0o700); err != nil {
		return fmt.Errorf("failed to create .ssh directory at %s: %w", sshDir, err)
	}

	return nil
}

// =========================================================================
//  Permanent Blocks Records
// =========================================================================

// Stores or updates a permanent block entry.
func UpsertPermanentBlock(ctx context.Context, rec PermanentBlockRecord) error {
	if db == nil {
		return errors.New("storage not initialised")
	}
	if rec.IP == "" || rec.Integration == "" {
		return errors.New("ip and integration are required")
	}
	now := time.Now().UTC()
	if rec.CreatedAt.IsZero() {
		rec.CreatedAt = now
	}
	rec.UpdatedAt = now
	if rec.Status == "" {
		rec.Status = "blocked"
	}

	const query = `
INSERT INTO permanent_blocks (ip, integration, status, details, message, server_id, created_at, updated_at)
VALUES (?, ?, ?, ?, ?, ?, ?, ?)
ON CONFLICT(ip, integration) DO UPDATE SET
	status = excluded.status,
	details = excluded.details,
	message = excluded.message,
	server_id = excluded.server_id,
	updated_at = excluded.updated_at`

	_, err := db.ExecContext(ctx, query,
		rec.IP,
		rec.Integration,
		rec.Status,
		rec.Details,
		rec.Message,
		rec.ServerID,
		rec.CreatedAt.Format(time.RFC3339Nano),
		rec.UpdatedAt.Format(time.RFC3339Nano),
	)
	return err
}

// Returns a permanent block entry.
func GetPermanentBlock(ctx context.Context, ip, integration string) (PermanentBlockRecord, bool, error) {
	if db == nil {
		return PermanentBlockRecord{}, false, errors.New("storage not initialised")
	}
	if ip == "" || integration == "" {
		return PermanentBlockRecord{}, false, errors.New("ip and integration are required")
	}

	row := db.QueryRowContext(ctx, `
SELECT id, ip, integration, status, details, message, server_id, created_at, updated_at
FROM permanent_blocks
WHERE ip = ? AND integration = ?`, ip, integration)

	var rec PermanentBlockRecord
	var createdAt, updatedAt sql.NullString
	if err := row.Scan(&rec.ID, &rec.IP, &rec.Integration, &rec.Status, &rec.Details, &rec.Message, &rec.ServerID, &createdAt, &updatedAt); err != nil {
		if errors.Is(err, sql.ErrNoRows) {
			return PermanentBlockRecord{}, false, nil
		}
		return PermanentBlockRecord{}, false, err
	}
	if createdAt.Valid {
		if ts, err := time.Parse(time.RFC3339Nano, createdAt.String); err == nil {
			rec.CreatedAt = ts
		}
	}
	if updatedAt.Valid {
		if ts, err := time.Parse(time.RFC3339Nano, updatedAt.String); err == nil {
			rec.UpdatedAt = ts
		}
	}
	return rec, true, nil
}

// Returns recent permanent block entries.
func ListPermanentBlocks(ctx context.Context, limit int) ([]PermanentBlockRecord, error) {
	if db == nil {
		return nil, errors.New("storage not initialised")
	}
	if limit <= 0 || limit > 500 {
		limit = 100
	}

	rows, err := db.QueryContext(ctx, `
SELECT id, ip, integration, status, details, message, server_id, created_at, updated_at
FROM permanent_blocks
ORDER BY updated_at DESC
LIMIT ?`, limit)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var records []PermanentBlockRecord
	for rows.Next() {
		var rec PermanentBlockRecord
		var createdAt, updatedAt sql.NullString
		if err := rows.Scan(&rec.ID, &rec.IP, &rec.Integration, &rec.Status, &rec.Details, &rec.Message, &rec.ServerID, &createdAt, &updatedAt); err != nil {
			return nil, err
		}
		if createdAt.Valid {
			if ts, err := time.Parse(time.RFC3339Nano, createdAt.String); err == nil {
				rec.CreatedAt = ts
			}
		}
		if updatedAt.Valid {
			if ts, err := time.Parse(time.RFC3339Nano, updatedAt.String); err == nil {
				rec.UpdatedAt = ts
			}
		}
		records = append(records, rec)
	}
	return records, rows.Err()
}

// Returns true when IP is currently blocked by integration.
func IsPermanentBlockActive(ctx context.Context, ip, integration string) (bool, error) {
	rec, found, err := GetPermanentBlock(ctx, ip, integration)
	if err != nil || !found {
		return false, err
	}
	return rec.Status == "blocked", nil
}