// Package cluster provides cluster-level operations for OpenSearch administration.
package cluster

import (
	"context"
	"encoding/json"
	"fmt"
	"os"

	"es-demo/client"

	"github.com/opensearch-project/opensearch-go/v2/opensearchapi"
)

// Info represents essential information about the OpenSearch cluster.
type Info struct {
	Name        string `json:"name"`
	ClusterName string `json:"cluster_name"`
	ClusterUUID string `json:"cluster_uuid"`
	Version     struct {
		Number                           string `json:"number"`
		BuildType                        string `json:"build_type"`
		BuildHash                        string `json:"build_hash"`
		BuildDate                        string `json:"build_date"`
		BuildSnapshot                    bool   `json:"build_snapshot"`
		LuceneVersion                    string `json:"lucene_version"`
		MinimumWireCompatibilityVersion  string `json:"minimum_wire_compatibility_version"`
		MinimumIndexCompatibilityVersion string `json:"minimum_index_compatibility_version"`
	} `json:"version"`
	Tagline string `json:"tagline"`
}

// GetInfo retrieves essential information about the OpenSearch cluster.
// It returns the cluster information or an error if the request fails.
func GetInfo(ctx context.Context, c *client.Client) (*Info, error) {
	req := opensearchapi.InfoRequest{}

	res, err := req.Do(ctx, c.GetClient())
	if err != nil {
		return nil, fmt.Errorf("failed to execute info request: %w", err)
	}
	defer func() {
		if closeErr := res.Body.Close(); closeErr != nil {
			fmt.Fprintf(os.Stderr, "warning: failed to close response body: %v\n", closeErr)
		}
	}()

	if res.IsError() {
		return nil, fmt.Errorf("request failed with status: %s", res.Status())
	}

	var info Info
	if err := json.NewDecoder(res.Body).Decode(&info); err != nil {
		return nil, fmt.Errorf("failed to decode cluster info: %w", err)
	}

	return &info, nil
}