package objectstorage

import (
	"bytes"
	"context"
	"fmt"
	"io"
	"strings"

	"github.com/minio/minio-go/v7"
	"github.com/minio/minio-go/v7/pkg/credentials"
	"go.uber.org/zap"

	"github.com/geo-platform/tenant-api/internal/shared/config"
	"github.com/geo-platform/tenant-api/internal/shared/middleware"
)

type minioClient struct {
	client *minio.Client
	bucket string
	region string
	logger *zap.Logger
	cfg    config.ObjectStorageConfig
}

func NewMinIOClient(cfg config.ObjectStorageConfig, logger *zap.Logger) Client {
	endpoint := strings.TrimSpace(cfg.Endpoint)
	accessKey := strings.TrimSpace(cfg.AccessKey)
	secretKey := strings.TrimSpace(cfg.SecretKey)
	bucket := strings.TrimSpace(cfg.Bucket)
	if endpoint == "" || accessKey == "" || secretKey == "" || bucket == "" {
		return disabledClient{reason: "missing object_storage minio endpoint/access_key/secret_key/bucket"}
	}

	client, err := minio.New(endpoint, &minio.Options{
		Creds:  credentials.NewStaticV4(accessKey, secretKey, ""),
		Secure: cfg.UseSSL,
		Region: strings.TrimSpace(cfg.Region),
	})
	if err != nil {
		return disabledClient{reason: fmt.Sprintf("init minio client failed: %v", err)}
	}

	return &minioClient{
		client: client,
		bucket: bucket,
		region: strings.TrimSpace(cfg.Region),
		logger: logger,
		cfg:    cfg,
	}
}

func (c *minioClient) Validate() error {
	if c == nil || c.client == nil {
		return fmt.Errorf("%w: minio client is not initialized", ErrNotConfigured)
	}
	if strings.TrimSpace(c.bucket) == "" {
		return fmt.Errorf("%w: minio bucket is empty", ErrNotConfigured)
	}
	return nil
}

func (c *minioClient) PutBytes(
	ctx context.Context,
	objectKey string,
	content []byte,
	contentType string,
) error {
	if err := c.Validate(); err != nil {
		return err
	}
	if strings.TrimSpace(objectKey) == "" {
		return fmt.Errorf("object key is required")
	}

	exists, err := c.client.BucketExists(ctx, c.bucket)
	if err != nil {
		c.logError(ctx, "minio bucket exists check failed",
			zap.String("bucket", c.bucket),
			zap.String("object_key", objectKey),
			zap.Error(err),
		)
		return fmt.Errorf("check minio bucket: %w", err)
	}
	if !exists {
		if err := c.client.MakeBucket(ctx, c.bucket, minio.MakeBucketOptions{Region: c.region}); err != nil {
			c.logError(ctx, "minio create bucket failed",
				zap.String("bucket", c.bucket),
				zap.String("object_key", objectKey),
				zap.Error(err),
			)
			return fmt.Errorf("create minio bucket: %w", err)
		}
	}

	_, err = c.client.PutObject(ctx, c.bucket, objectKey, bytes.NewReader(content), int64(len(content)), minio.PutObjectOptions{
		ContentType: contentType,
	})
	if err != nil {
		c.logError(ctx, "minio put object failed",
			zap.String("bucket", c.bucket),
			zap.String("object_key", objectKey),
			zap.Int("content_size", len(content)),
			zap.Error(err),
		)
		return fmt.Errorf("put minio object: %w", err)
	}
	return nil
}

func (c *minioClient) GetBytes(ctx context.Context, objectKey string) ([]byte, error) {
	if err := c.Validate(); err != nil {
		return nil, err
	}
	reader, err := c.client.GetObject(ctx, c.bucket, objectKey, minio.GetObjectOptions{})
	if err != nil {
		c.logError(ctx, "minio get object failed",
			zap.String("bucket", c.bucket),
			zap.String("object_key", objectKey),
			zap.Error(err),
		)
		return nil, fmt.Errorf("get minio object: %w", err)
	}
	defer reader.Close()

	data, err := io.ReadAll(reader)
	if err != nil {
		c.logError(ctx, "minio read object failed",
			zap.String("bucket", c.bucket),
			zap.String("object_key", objectKey),
			zap.Error(err),
		)
		return nil, fmt.Errorf("read minio object: %w", err)
	}
	return data, nil
}

func (c *minioClient) Delete(ctx context.Context, objectKey string) error {
	if err := c.Validate(); err != nil {
		return err
	}
	if strings.TrimSpace(objectKey) == "" {
		return nil
	}

	err := c.client.RemoveObject(ctx, c.bucket, objectKey, minio.RemoveObjectOptions{})
	if err != nil {
		c.logError(ctx, "minio delete object failed",
			zap.String("bucket", c.bucket),
			zap.String("object_key", objectKey),
			zap.Error(err),
		)
		return fmt.Errorf("delete minio object: %w", err)
	}
	return nil
}

func (c *minioClient) PublicURL(objectKey string) (string, error) {
	if err := c.Validate(); err != nil {
		return "", err
	}
	return buildPublicURL(c.cfg, objectKey, false)
}

func (c *minioClient) logError(ctx context.Context, msg string, fields ...zap.Field) {
	if c == nil || c.logger == nil {
		return
	}
	if requestID := middleware.RequestIDFromContext(ctx); requestID != "" {
		fields = append(fields, zap.String("request_id", requestID))
	}
	c.logger.Error(msg, fields...)
}