package bind

import (
	"context"
	"fmt"
	"strings"
)

// Rndc runs `rndc <args...>` on a pod and returns its output.
func (e *Executor) Rndc(ctx context.Context, namespace, pod string, args ...string) (string, error) {
	base := []string{RndcBin, "-c", RndcConfPath}
	return e.Exec(ctx, namespace, pod, append(base, args...), "")
}

// Reconfig reloads named.conf and any newly added/removed zones without a full
// restart.
func (e *Executor) Reconfig(ctx context.Context, namespace, pod string) error {
	_, err := e.Rndc(ctx, namespace, pod, "reconfig")
	return err
}

// AddZone provisions a zone at runtime via `rndc addzone`. config is the inner
// zone clause, e.g. `{ type primary; file "db.example"; allow-update { key k; }; };`.
func (e *Executor) AddZone(ctx context.Context, namespace, pod, zone, view, config string) error {
	args := []string{"addzone", zone}
	if view != "" {
		args = append(args, "in", view)
	}
	args = append(args, config)
	out, err := e.Rndc(ctx, namespace, pod, args...)
	if err != nil {
		// addzone fails if the zone already exists; fall back to modzone so the
		// operation is idempotent.
		if strings.Contains(err.Error(), "already exists") || strings.Contains(out, "already exists") {
			return e.ModZone(ctx, namespace, pod, zone, view, config)
		}
		return err
	}
	return nil
}

// ModZone updates an existing runtime-added zone's configuration.
func (e *Executor) ModZone(ctx context.Context, namespace, pod, zone, view, config string) error {
	args := []string{"modzone", zone}
	if view != "" {
		args = append(args, "in", view)
	}
	args = append(args, config)
	_, err := e.Rndc(ctx, namespace, pod, args...)
	return err
}

// DelZone removes a runtime-added zone. A missing zone is treated as success.
func (e *Executor) DelZone(ctx context.Context, namespace, pod, zone, view string) error {
	args := []string{"delzone", zone}
	if view != "" {
		args = append(args, "in", view)
	}
	out, err := e.Rndc(ctx, namespace, pod, args...)
	if err != nil && (strings.Contains(err.Error(), "not found") || strings.Contains(out, "not found")) {
		return nil
	}
	return err
}

// ZoneSerial returns the current SOA serial for a zone via `rndc zonestatus`.
func (e *Executor) ZoneSerial(ctx context.Context, namespace, pod, zone, view string) (int64, error) {
	args := []string{"zonestatus", zone}
	if view != "" {
		args = append(args, "in", view)
	}
	out, err := e.Rndc(ctx, namespace, pod, args...)
	if err != nil {
		return 0, err
	}
	for _, line := range strings.Split(out, "\n") {
		line = strings.TrimSpace(line)
		if strings.HasPrefix(line, "serial:") {
			var serial int64
			if _, err := fmt.Sscanf(line, "serial: %d", &serial); err == nil {
				return serial, nil
			}
		}
	}
	return 0, nil
}