// Package ntp provides CRUD against ntp_settings (single-row) and
// ntp_pools. Renderer in internal/chrony consumes the same data.
package ntp

import (
	"context"
	"errors"

	"github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgxpool"

	"git.netcell-it.de/projekte/edgeguard-native/internal/models"
)

var ErrPoolNotFound = errors.New("ntp pool not found")

type Repo struct {
	Pool *pgxpool.Pool
}

func New(pool *pgxpool.Pool) *Repo { return &Repo{Pool: pool} }

// ── Settings ───────────────────────────────────────────────────

func (r *Repo) GetSettings(ctx context.Context) (*models.NTPSettings, error) {
	row := r.Pool.QueryRow(ctx, `
SELECT id, listen_addresses, allow_acl, serve_clients,
       makestep_secs, makestep_limit, rtcsync, leapsectz, updated_at
FROM ntp_settings WHERE id=1`)
	var s models.NTPSettings
	if err := row.Scan(&s.ID, &s.ListenAddresses, &s.AllowACL, &s.ServeClients,
		&s.MakestepSecs, &s.MakestepLimit, &s.RTCSync, &s.LeapsecTZ, &s.UpdatedAt); err != nil {
		return nil, err
	}
	return &s, nil
}

func (r *Repo) UpdateSettings(ctx context.Context, s models.NTPSettings) (*models.NTPSettings, error) {
	row := r.Pool.QueryRow(ctx, `
UPDATE ntp_settings SET
   listen_addresses=$1, allow_acl=$2, serve_clients=$3,
   makestep_secs=$4, makestep_limit=$5, rtcsync=$6, leapsectz=$7,
   updated_at=NOW()
WHERE id=1
RETURNING id, listen_addresses, allow_acl, serve_clients,
          makestep_secs, makestep_limit, rtcsync, leapsectz, updated_at`,
		s.ListenAddresses, s.AllowACL, s.ServeClients,
		s.MakestepSecs, s.MakestepLimit, s.RTCSync, s.LeapsecTZ)
	var out models.NTPSettings
	if err := row.Scan(&out.ID, &out.ListenAddresses, &out.AllowACL, &out.ServeClients,
		&out.MakestepSecs, &out.MakestepLimit, &out.RTCSync, &out.LeapsecTZ, &out.UpdatedAt); err != nil {
		return nil, err
	}
	return &out, nil
}

// ── Pools ──────────────────────────────────────────────────────

const poolSelect = `
SELECT id, kind, address, iburst, prefer, minpoll, maxpoll, active,
       description, created_at, updated_at
FROM ntp_pools
`

func (r *Repo) ListPools(ctx context.Context) ([]models.NTPPool, error) {
	rows, err := r.Pool.Query(ctx, poolSelect+" ORDER BY id ASC")
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	out := make([]models.NTPPool, 0, 8)
	for rows.Next() {
		p, err := scanPool(rows)
		if err != nil {
			return nil, err
		}
		out = append(out, *p)
	}
	return out, rows.Err()
}

func (r *Repo) GetPool(ctx context.Context, id int64) (*models.NTPPool, error) {
	row := r.Pool.QueryRow(ctx, poolSelect+" WHERE id=$1", id)
	p, err := scanPool(row)
	if err != nil {
		if errors.Is(err, pgx.ErrNoRows) {
			return nil, ErrPoolNotFound
		}
		return nil, err
	}
	return p, nil
}

func (r *Repo) CreatePool(ctx context.Context, p models.NTPPool) (*models.NTPPool, error) {
	row := r.Pool.QueryRow(ctx, `
INSERT INTO ntp_pools (kind, address, iburst, prefer, minpoll, maxpoll, active, description)
VALUES ($1,$2,$3,$4,$5,$6,$7,$8)
RETURNING id, kind, address, iburst, prefer, minpoll, maxpoll, active,
          description, created_at, updated_at`,
		p.Kind, p.Address, p.Iburst, p.Prefer, p.MinPoll, p.MaxPoll, p.Active, p.Description)
	return scanPool(row)
}

func (r *Repo) UpdatePool(ctx context.Context, id int64, p models.NTPPool) (*models.NTPPool, error) {
	row := r.Pool.QueryRow(ctx, `
UPDATE ntp_pools SET kind=$1, address=$2, iburst=$3, prefer=$4,
   minpoll=$5, maxpoll=$6, active=$7, description=$8, updated_at=NOW()
WHERE id=$9
RETURNING id, kind, address, iburst, prefer, minpoll, maxpoll, active,
          description, created_at, updated_at`,
		p.Kind, p.Address, p.Iburst, p.Prefer, p.MinPoll, p.MaxPoll, p.Active, p.Description, id)
	out, err := scanPool(row)
	if err != nil {
		if errors.Is(err, pgx.ErrNoRows) {
			return nil, ErrPoolNotFound
		}
		return nil, err
	}
	return out, nil
}

func (r *Repo) DeletePool(ctx context.Context, id int64) error {
	tag, err := r.Pool.Exec(ctx, `DELETE FROM ntp_pools WHERE id=$1`, id)
	if err != nil {
		return err
	}
	if tag.RowsAffected() == 0 {
		return ErrPoolNotFound
	}
	return nil
}

func scanPool(row interface{ Scan(...any) error }) (*models.NTPPool, error) {
	var p models.NTPPool
	if err := row.Scan(
		&p.ID, &p.Kind, &p.Address, &p.Iburst, &p.Prefer,
		&p.MinPoll, &p.MaxPoll, &p.Active, &p.Description,
		&p.CreatedAt, &p.UpdatedAt,
	); err != nil {
		return nil, err
	}
	return &p, nil
}