package firewall

import (
	"context"
	"errors"

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

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

var ErrRuleNotFound = errors.New("firewall rule not found")

type RulesRepo struct {
	Pool *pgxpool.Pool
}

func NewRulesRepo(pool *pgxpool.Pool) *RulesRepo { return &RulesRepo{Pool: pool} }

const ruleBaseSelect = `
SELECT id, name, priority, enabled, action,
       src_zone, src_address_object_id, src_address_group_id, src_cidr,
       dst_zone, dst_address_object_id, dst_address_group_id, dst_cidr,
       service_object_id, service_group_id,
       log, comment, created_at, updated_at
FROM firewall_rules
`

func (r *RulesRepo) List(ctx context.Context) ([]models.FirewallRule, error) {
	rows, err := r.Pool.Query(ctx, ruleBaseSelect+" ORDER BY priority DESC, id ASC")
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	out := make([]models.FirewallRule, 0, 16)
	for rows.Next() {
		x, err := scanRule(rows)
		if err != nil {
			return nil, err
		}
		out = append(out, *x)
	}
	return out, rows.Err()
}

func (r *RulesRepo) Get(ctx context.Context, id int64) (*models.FirewallRule, error) {
	row := r.Pool.QueryRow(ctx, ruleBaseSelect+" WHERE id = $1", id)
	x, err := scanRule(row)
	if err != nil {
		if errors.Is(err, pgx.ErrNoRows) {
			return nil, ErrRuleNotFound
		}
		return nil, err
	}
	return x, nil
}

func (r *RulesRepo) Create(ctx context.Context, x models.FirewallRule) (*models.FirewallRule, error) {
	row := r.Pool.QueryRow(ctx, `
INSERT INTO firewall_rules (
    name, priority, enabled, action,
    src_zone, src_address_object_id, src_address_group_id, src_cidr,
    dst_zone, dst_address_object_id, dst_address_group_id, dst_cidr,
    service_object_id, service_group_id,
    log, comment
) VALUES (
    $1, $2, $3, $4,
    $5, $6, $7, $8,
    $9, $10, $11, $12,
    $13, $14,
    $15, $16
)
RETURNING id, name, priority, enabled, action,
          src_zone, src_address_object_id, src_address_group_id, src_cidr,
          dst_zone, dst_address_object_id, dst_address_group_id, dst_cidr,
          service_object_id, service_group_id,
          log, comment, created_at, updated_at`,
		x.Name, x.Priority, x.Enabled, x.Action,
		x.SrcZone, x.SrcAddressObjectID, x.SrcAddressGroupID, x.SrcCIDR,
		x.DstZone, x.DstAddressObjectID, x.DstAddressGroupID, x.DstCIDR,
		x.ServiceObjectID, x.ServiceGroupID,
		x.Log, x.Comment)
	return scanRule(row)
}

func (r *RulesRepo) Update(ctx context.Context, id int64, x models.FirewallRule) (*models.FirewallRule, error) {
	row := r.Pool.QueryRow(ctx, `
UPDATE firewall_rules SET
   name = $1, priority = $2, enabled = $3, action = $4,
   src_zone = $5, src_address_object_id = $6, src_address_group_id = $7, src_cidr = $8,
   dst_zone = $9, dst_address_object_id = $10, dst_address_group_id = $11, dst_cidr = $12,
   service_object_id = $13, service_group_id = $14,
   log = $15, comment = $16, updated_at = NOW()
WHERE id = $17
RETURNING id, name, priority, enabled, action,
          src_zone, src_address_object_id, src_address_group_id, src_cidr,
          dst_zone, dst_address_object_id, dst_address_group_id, dst_cidr,
          service_object_id, service_group_id,
          log, comment, created_at, updated_at`,
		x.Name, x.Priority, x.Enabled, x.Action,
		x.SrcZone, x.SrcAddressObjectID, x.SrcAddressGroupID, x.SrcCIDR,
		x.DstZone, x.DstAddressObjectID, x.DstAddressGroupID, x.DstCIDR,
		x.ServiceObjectID, x.ServiceGroupID,
		x.Log, x.Comment, id)
	out, err := scanRule(row)
	if err != nil {
		if errors.Is(err, pgx.ErrNoRows) {
			return nil, ErrRuleNotFound
		}
		return nil, err
	}
	return out, nil
}

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

func scanRule(row interface{ Scan(...any) error }) (*models.FirewallRule, error) {
	var x models.FirewallRule
	if err := row.Scan(
		&x.ID, &x.Name, &x.Priority, &x.Enabled, &x.Action,
		&x.SrcZone, &x.SrcAddressObjectID, &x.SrcAddressGroupID, &x.SrcCIDR,
		&x.DstZone, &x.DstAddressObjectID, &x.DstAddressGroupID, &x.DstCIDR,
		&x.ServiceObjectID, &x.ServiceGroupID,
		&x.Log, &x.Comment, &x.CreatedAt, &x.UpdatedAt,
	); err != nil {
		return nil, err
	}
	return &x, nil
}