package database

import (
	"context"
	"database/sql"
	"fmt"
	"time"

	"git.eeqj.de/sneak/vaultik/internal/log"
)

type BlobRepository struct {
	db *DB
}

func NewBlobRepository(db *DB) *BlobRepository {
	return &BlobRepository{db: db}
}

func (r *BlobRepository) Create(ctx context.Context, tx *sql.Tx, blob *Blob) error {
	query := `
		INSERT INTO blobs (id, blob_hash, created_ts, finished_ts, uncompressed_size, compressed_size, uploaded_ts)
		VALUES (?, ?, ?, ?, ?, ?, ?)
	`

	var finishedTS, uploadedTS *int64
	if blob.FinishedTS != nil {
		ts := blob.FinishedTS.Unix()
		finishedTS = &ts
	}
	if blob.UploadedTS != nil {
		ts := blob.UploadedTS.Unix()
		uploadedTS = &ts
	}

	var err error
	if tx != nil {
		_, err = tx.ExecContext(ctx, query, blob.ID, blob.Hash, blob.CreatedTS.Unix(),
			finishedTS, blob.UncompressedSize, blob.CompressedSize, uploadedTS)
	} else {
		_, err = r.db.ExecWithLog(ctx, query, blob.ID, blob.Hash, blob.CreatedTS.Unix(),
			finishedTS, blob.UncompressedSize, blob.CompressedSize, uploadedTS)
	}

	if err != nil {
		return fmt.Errorf("inserting blob: %w", err)
	}

	return nil
}

func (r *BlobRepository) GetByHash(ctx context.Context, hash string) (*Blob, error) {
	query := `
		SELECT id, blob_hash, created_ts, finished_ts, uncompressed_size, compressed_size, uploaded_ts
		FROM blobs
		WHERE blob_hash = ?
	`

	var blob Blob
	var createdTSUnix int64
	var finishedTSUnix, uploadedTSUnix sql.NullInt64

	err := r.db.conn.QueryRowContext(ctx, query, hash).Scan(
		&blob.ID,
		&blob.Hash,
		&createdTSUnix,
		&finishedTSUnix,
		&blob.UncompressedSize,
		&blob.CompressedSize,
		&uploadedTSUnix,
	)

	if err == sql.ErrNoRows {
		return nil, nil
	}
	if err != nil {
		return nil, fmt.Errorf("querying blob: %w", err)
	}

	blob.CreatedTS = time.Unix(createdTSUnix, 0).UTC()
	if finishedTSUnix.Valid {
		ts := time.Unix(finishedTSUnix.Int64, 0).UTC()
		blob.FinishedTS = &ts
	}
	if uploadedTSUnix.Valid {
		ts := time.Unix(uploadedTSUnix.Int64, 0).UTC()
		blob.UploadedTS = &ts
	}
	return &blob, nil
}

// GetByID retrieves a blob by its ID
func (r *BlobRepository) GetByID(ctx context.Context, id string) (*Blob, error) {
	query := `
		SELECT id, blob_hash, created_ts, finished_ts, uncompressed_size, compressed_size, uploaded_ts
		FROM blobs
		WHERE id = ?
	`

	var blob Blob
	var createdTSUnix int64
	var finishedTSUnix, uploadedTSUnix sql.NullInt64

	err := r.db.conn.QueryRowContext(ctx, query, id).Scan(
		&blob.ID,
		&blob.Hash,
		&createdTSUnix,
		&finishedTSUnix,
		&blob.UncompressedSize,
		&blob.CompressedSize,
		&uploadedTSUnix,
	)

	if err == sql.ErrNoRows {
		return nil, nil
	}
	if err != nil {
		return nil, fmt.Errorf("querying blob: %w", err)
	}

	blob.CreatedTS = time.Unix(createdTSUnix, 0).UTC()
	if finishedTSUnix.Valid {
		ts := time.Unix(finishedTSUnix.Int64, 0).UTC()
		blob.FinishedTS = &ts
	}
	if uploadedTSUnix.Valid {
		ts := time.Unix(uploadedTSUnix.Int64, 0).UTC()
		blob.UploadedTS = &ts
	}
	return &blob, nil
}

// UpdateFinished updates a blob when it's finalized
func (r *BlobRepository) UpdateFinished(ctx context.Context, tx *sql.Tx, id string, hash string, uncompressedSize, compressedSize int64) error {
	query := `
		UPDATE blobs 
		SET blob_hash = ?, finished_ts = ?, uncompressed_size = ?, compressed_size = ?
		WHERE id = ?
	`

	now := time.Now().UTC().Unix()
	var err error
	if tx != nil {
		_, err = tx.ExecContext(ctx, query, hash, now, uncompressedSize, compressedSize, id)
	} else {
		_, err = r.db.ExecWithLog(ctx, query, hash, now, uncompressedSize, compressedSize, id)
	}

	if err != nil {
		return fmt.Errorf("updating blob: %w", err)
	}

	return nil
}

// UpdateUploaded marks a blob as uploaded
func (r *BlobRepository) UpdateUploaded(ctx context.Context, tx *sql.Tx, id string) error {
	query := `
		UPDATE blobs 
		SET uploaded_ts = ?
		WHERE id = ?
	`

	now := time.Now().UTC().Unix()
	var err error
	if tx != nil {
		_, err = tx.ExecContext(ctx, query, now, id)
	} else {
		_, err = r.db.ExecWithLog(ctx, query, now, id)
	}

	if err != nil {
		return fmt.Errorf("marking blob as uploaded: %w", err)
	}

	return nil
}

// DeleteOrphaned deletes blobs that are not referenced by any snapshot
func (r *BlobRepository) DeleteOrphaned(ctx context.Context) error {
	query := `
		DELETE FROM blobs 
		WHERE NOT EXISTS (
			SELECT 1 FROM snapshot_blobs 
			WHERE snapshot_blobs.blob_id = blobs.id
		)
	`

	result, err := r.db.ExecWithLog(ctx, query)
	if err != nil {
		return fmt.Errorf("deleting orphaned blobs: %w", err)
	}

	rowsAffected, _ := result.RowsAffected()
	if rowsAffected > 0 {
		log.Debug("Deleted orphaned blobs", "count", rowsAffected)
	}

	return nil
}