/*
Copyright © 2026 Thomas von Dein

This program 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.

This program 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 <http://www.gnu.org/licenses/>.
*/
package es

import (
	"context"
	"errors"
	"fmt"
	"log/slog"

	"codeberg.org/scip/esctl/pkg/cfg"
	"github.com/elastic/go-elasticsearch/v9/typedapi/types"
)

const (
	shard_pause = `cluster.routing.allocation.enable`
)

func CcrShardPause(conf *cfg.Config) error {
	return ClusterSettingsSetSingle(conf, shard_pause, "none")
}

func CcrShardResume(conf *cfg.Config) error {
	return ClusterSettingsSetSingle(conf, shard_pause, "all")
}

func CcrStatus(conf *cfg.Config, leader, follower string) error {
	if !checkClusterIsLeader(conf, leader) {
		if !checkClusterIsLeader(conf, follower) {
			return errors.New("leader/follower attribution is invalid, both clusters are followers")
		}

		// reverse attribution
		f := follower
		follower = leader
		leader = f
		slog.Debug("leader/follower attribution is invalid, reversing", "leader", leader, "follower", follower)
	}

	indices := ClusterIndices{}

	for _, alias := range []string{leader, follower} {
		cat := conf.Clusters[alias].ES.Cat.Indices().
			// we need to add custom request headers, required for older ES instances
			Header("content-type", "application/json").
			Header("accept", "application/json")

		res, err := cat.Do(context.Background())
		if err != nil {
			return fmt.Errorf("failed to get indicies on %s: %s", alias, err)
		}

		indices[alias] = make(map[string]*types.IndicesRecord, len(res))

		for _, index := range res {
			indices[alias][*index.Index] = &index
		}
	}

	if !checkClusterStatus(conf, leader, follower) {
		return errors.New("one of the two clusters is in a failed state")
	}

	findIlmErrors(conf, leader, follower)

	if findIndicesOnlyOnLeader(conf, indices, leader, follower) &&
		findOrphanedIndices(conf, indices, leader, follower) &&
		findFailedFollowerIndices(conf, indices, follower) {
		fmt.Println("everything's hunky-dory.")
	}

	return nil
}