package blobstor

import (
	"context"
	"errors"
	"fmt"

	"git.frostfs.info/TrueCloudLab/frostfs-node/internal/logs"
	"git.frostfs.info/TrueCloudLab/frostfs-node/pkg/local_object_storage/shard/mode"
	"go.uber.org/zap"
)

// Open opens BlobStor.
func (b *BlobStor) Open(ctx context.Context, mode mode.Mode) error {
	b.log.Debug(logs.BlobstorOpening)

	b.modeMtx.Lock()
	defer b.modeMtx.Unlock()
	b.mode = mode

	err := b.openBlobStor(ctx, mode)
	if err != nil {
		return err
	}
	b.metrics.SetMode(mode.ReadOnly())

	return nil
}

func (b *BlobStor) openBlobStor(ctx context.Context, mode mode.Mode) error {
	readOnly := mode.ReadOnly()
	for i := range b.storage {
		select {
		case <-ctx.Done():
			return ctx.Err()
		default:
		}
		err := b.storage[i].Storage.Open(readOnly)
		if err != nil {
			return err
		}
	}
	return nil
}

// ErrInitBlobovniczas is returned when blobovnicza initialization fails.
var ErrInitBlobovniczas = errors.New("failure on blobovnicza initialization stage")

// Init initializes internal data structures and system resources.
//
// If BlobStor is already initialized, no action is taken.
//
// Returns wrapped ErrInitBlobovniczas on blobovnicza tree's initializaiton failure.
func (b *BlobStor) Init() error {
	b.log.Debug(logs.BlobstorInitializing)

	if err := b.compression.Init(); err != nil {
		return err
	}

	for i := range b.storage {
		err := b.storage[i].Storage.Init()
		if err != nil {
			return fmt.Errorf("%w: %v", ErrInitBlobovniczas, err)
		}
	}
	return nil
}

// Close releases all internal resources of BlobStor.
func (b *BlobStor) Close() error {
	b.log.Debug(logs.BlobstorClosing)

	var firstErr error
	for i := range b.storage {
		err := b.storage[i].Storage.Close()
		if err != nil {
			b.log.Info(logs.BlobstorCouldntCloseStorage, zap.String("error", err.Error()))
			if firstErr == nil {
				firstErr = err
			}
			continue
		}
	}

	err := b.compression.Close()
	if firstErr == nil {
		firstErr = err
	}
	if firstErr == nil {
		b.metrics.Close()
	}
	return firstErr
}