/*
 * Copyright (C) 2020-2022, IrineSistiana
 *
 * This file is part of mosdns.
 *
 * mosdns is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * mosdns is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

package arbitrary

import (
	"bytes"
	"context"
	"fmt"
	"github.com/IrineSistiana/mosdns/v5/coremain"
	"github.com/IrineSistiana/mosdns/v5/pkg/query_context"
	"github.com/IrineSistiana/mosdns/v5/pkg/zone_file"
	"github.com/IrineSistiana/mosdns/v5/plugin/executable/sequence"
	"os"
	"strings"
)

const PluginType = "arbitrary"

func init() {
	coremain.RegNewPluginFunc(PluginType, Init, func() any { return new(Args) })
}

type Args struct {
	Rules []string `yaml:"rules"`
	Files []string `yaml:"files"`
}

var _ sequence.Executable = (*Arbitrary)(nil)

type Arbitrary struct {
	m *zone_file.Matcher
}

func NewArbitrary(args *Args) (*Arbitrary, error) {
	m := new(zone_file.Matcher)
	for i, s := range args.Rules {
		if err := m.Load(strings.NewReader(s)); err != nil {
			return nil, fmt.Errorf("failed to load rr #%d [%s], %w", i, s, err)
		}
	}
	for i, file := range args.Files {
		b, err := os.ReadFile(file)
		if err != nil {
			return nil, fmt.Errorf("failed to read file #%d [%s], %w", i, file, err)
		}
		if err := m.Load(bytes.NewReader(b)); err != nil {
			return nil, fmt.Errorf("failed to load rr file #%d [%s], %w", i, file, err)
		}
	}
	return &Arbitrary{
		m: m,
	}, nil
}

func (a *Arbitrary) Exec(_ context.Context, qCtx *query_context.Context) error {
	if r := a.m.Reply(qCtx.Q()); r != nil {
		qCtx.SetResponse(r)
	}
	return nil
}

func Init(_ *coremain.BP, v any) (any, error) {
	args := v.(*Args)
	return NewArbitrary(args)
}