package database

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

type FileChunkRepository struct {
	db *DB
}

func NewFileChunkRepository(db *DB) *FileChunkRepository {
	return &FileChunkRepository{db: db}
}

func (r *FileChunkRepository) Create(ctx context.Context, tx *sql.Tx, fc *FileChunk) error {
	query := `
		INSERT INTO file_chunks (file_id, idx, chunk_hash)
		VALUES (?, ?, ?)
		ON CONFLICT(file_id, idx) DO NOTHING
	`

	var err error
	if tx != nil {
		_, err = tx.ExecContext(ctx, query, fc.FileID, fc.Idx, fc.ChunkHash)
	} else {
		_, err = r.db.ExecWithLog(ctx, query, fc.FileID, fc.Idx, fc.ChunkHash)
	}

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

	return nil
}

func (r *FileChunkRepository) GetByPath(ctx context.Context, path string) ([]*FileChunk, error) {
	query := `
		SELECT fc.file_id, fc.idx, fc.chunk_hash
		FROM file_chunks fc
		JOIN files f ON fc.file_id = f.id
		WHERE f.path = ?
		ORDER BY fc.idx
	`

	rows, err := r.db.conn.QueryContext(ctx, query, path)
	if err != nil {
		return nil, fmt.Errorf("querying file chunks: %w", err)
	}
	defer CloseRows(rows)

	var fileChunks []*FileChunk
	for rows.Next() {
		var fc FileChunk
		err := rows.Scan(&fc.FileID, &fc.Idx, &fc.ChunkHash)
		if err != nil {
			return nil, fmt.Errorf("scanning file chunk: %w", err)
		}
		fileChunks = append(fileChunks, &fc)
	}

	return fileChunks, rows.Err()
}

// GetByFileID retrieves file chunks by file ID
func (r *FileChunkRepository) GetByFileID(ctx context.Context, fileID string) ([]*FileChunk, error) {
	query := `
		SELECT file_id, idx, chunk_hash
		FROM file_chunks
		WHERE file_id = ?
		ORDER BY idx
	`

	rows, err := r.db.conn.QueryContext(ctx, query, fileID)
	if err != nil {
		return nil, fmt.Errorf("querying file chunks: %w", err)
	}
	defer CloseRows(rows)

	var fileChunks []*FileChunk
	for rows.Next() {
		var fc FileChunk
		err := rows.Scan(&fc.FileID, &fc.Idx, &fc.ChunkHash)
		if err != nil {
			return nil, fmt.Errorf("scanning file chunk: %w", err)
		}
		fileChunks = append(fileChunks, &fc)
	}

	return fileChunks, rows.Err()
}

// GetByPathTx retrieves file chunks within a transaction
func (r *FileChunkRepository) GetByPathTx(ctx context.Context, tx *sql.Tx, path string) ([]*FileChunk, error) {
	query := `
		SELECT fc.file_id, fc.idx, fc.chunk_hash
		FROM file_chunks fc
		JOIN files f ON fc.file_id = f.id
		WHERE f.path = ?
		ORDER BY fc.idx
	`

	LogSQL("GetByPathTx", query, path)
	rows, err := tx.QueryContext(ctx, query, path)
	if err != nil {
		return nil, fmt.Errorf("querying file chunks: %w", err)
	}
	defer CloseRows(rows)

	var fileChunks []*FileChunk
	for rows.Next() {
		var fc FileChunk
		err := rows.Scan(&fc.FileID, &fc.Idx, &fc.ChunkHash)
		if err != nil {
			return nil, fmt.Errorf("scanning file chunk: %w", err)
		}
		fileChunks = append(fileChunks, &fc)
	}
	LogSQL("GetByPathTx", "Complete", path, "count", len(fileChunks))

	return fileChunks, rows.Err()
}

func (r *FileChunkRepository) DeleteByPath(ctx context.Context, tx *sql.Tx, path string) error {
	query := `DELETE FROM file_chunks WHERE file_id = (SELECT id FROM files WHERE path = ?)`

	var err error
	if tx != nil {
		_, err = tx.ExecContext(ctx, query, path)
	} else {
		_, err = r.db.ExecWithLog(ctx, query, path)
	}

	if err != nil {
		return fmt.Errorf("deleting file chunks: %w", err)
	}

	return nil
}

// DeleteByFileID deletes all chunks for a file by its UUID
func (r *FileChunkRepository) DeleteByFileID(ctx context.Context, tx *sql.Tx, fileID string) error {
	query := `DELETE FROM file_chunks WHERE file_id = ?`

	var err error
	if tx != nil {
		_, err = tx.ExecContext(ctx, query, fileID)
	} else {
		_, err = r.db.ExecWithLog(ctx, query, fileID)
	}

	if err != nil {
		return fmt.Errorf("deleting file chunks: %w", err)
	}

	return nil
}

// GetByFile is an alias for GetByPath for compatibility
func (r *FileChunkRepository) GetByFile(ctx context.Context, path string) ([]*FileChunk, error) {
	LogSQL("GetByFile", "Starting", path)
	result, err := r.GetByPath(ctx, path)
	LogSQL("GetByFile", "Complete", path, "count", len(result))
	return result, err
}

// GetByFileTx retrieves file chunks within a transaction
func (r *FileChunkRepository) GetByFileTx(ctx context.Context, tx *sql.Tx, path string) ([]*FileChunk, error) {
	LogSQL("GetByFileTx", "Starting", path)
	result, err := r.GetByPathTx(ctx, tx, path)
	LogSQL("GetByFileTx", "Complete", path, "count", len(result))
	return result, err
}