Turso - is the SQLite compatible database written in Rust. One of the important features of the Turso - is native ability to sync database with the Cloud in both directions (push local changes and pull remote changes).

Your task is to generate EXTRA functionality on top of the existing Golang driver which will extend regular embedded with sync capability. Do not modify existing driver - its already implemented in the driver_db.go (based on bindings_db.go) Your task is to write extra code which will use abstractions driver_db.go + bindings_db.go and build sync support in the Gollang on top of it in the driver_sync.go file.

Rules

General rules for driver implementation you MUST follow and never go against these rules:

USE already implemented driver - DO NOT copy it
SET async_io=True for the driver database configuration - because partial sync support requires TURSO_IO to handled externally from the bindings
ADD context.Context in the methods when this make sense and we have control over method API
STRUCTURE of the implementation
- Declaration order of elements and semantic blocks MUST be exsactly the same
- (details and full enumerations omited in the example for brevity but you must generate full code)

package turso

struct TursoSyncDbConfig {
    // path to the main database file locally
    Path string
    
    // remote url for the sync
    // remote_url MUST be used in all sync engine operations: during bootstrap and all further operations
    RemoteUrl string
    
    // token for remote authentication
    // auth token value WILL not have any prefix and must be used as "Authorization" header prepended with "Bearer " prefix
    AuthToken string
    
    // optional unique client name (library MUST use `turso-sync-go` if omitted)
    ClientName string

    // long polling timeout
    LongPollTimeoutMs int
    
    // if not set, initial bootstrap phase will be skipped and caller must call .pull(...) explicitly in order to get initial state from remote
    // default value is true
    BootstrapIfEmpty *bool
    
    // if positive, prefix partial bootstrap strategy will be used
    PartialBootstrapStrategyPrefix int
    // if not empty, query partial bootstrap strategy will be used
    PartialBootstrapStrategyQuery string
    
    // pass it as-is to the underlying connection
    ExperimentalFeatures string
}

// statistics for the synced database.
type TursoSyncDbStats struct {
    // amount of local operations written since last Pull(...) call
	CdcOperations        int64
    // size of the main WAL file
	MainWalSize          int64
    // size of the revert WAL file
	RevertWalSize        int64
    // last successful pull time
	LastPullUnixTime     int64
    // last successful push time
	LastPushUnixTime     int64
    // total amount of bytes sent over the network (both Push and Pull operations are tracked together)
	NetworkSentBytes     int64
    // total amount of bytes received over the network (both Push and Pull operations are tracked together)
	NetworkReceivedBytes int64
    // opaque server revision - it MUST NOT be interpreted/parsed in any way
	Revision             string
}

// define public structs here
struct TursoSyncDb { ... }

// main constructor to create synced database
func NewTursoSyncDb(ctx context.Context, config TursoSyncDbConfig) (*TursoSyncDb, error) { ... }

// create turso db local connnection

// internal connector to integrate with database/sql pool
type tursoSyncConnector struct { db *TursoSyncDb }
func (c *tursoSyncConnector) Connect(ctx context.Context) (driver.Conn, error) { ... }
func (c *tursoSyncConnector) Driver() driver.Driver { return &tursoDbDriver{} }

// create tursodb connection using NewConnection(...) from driver_db.go and tursoSyncConnector helper
func (d *TursoSyncDb) Connect(ctx context.Context) (*sql.DB, error) { ... }

// implement EXTRA sync methods

// Pull fresh data from the remote
// Pull DO NOT sent any local changes to the remote and instead "rebase" them on top of new changes from remote
// Return true, if new changes were applied locally - otherwise return false
func (d *TursoSyncDb) Pull(ctx context.Context) (bool, error) { ... }

// Push local changes to the remote
// Push DO NOT fetch any remote changes
func (d *TursoSyncDb) Push(ctx context.Context) error { ... }

// Get stats for the synced database
func (d *TursoSyncDb) Stats(ctx context.Context) (TursoSyncDbStats, error) { ... }

// Checkpoint local WAL of the database
func (d *TursoSyncDb) Checkpoint(ctx context.Context) error { ... }

STREAM data from the http request to the completion in chunks and spin async operation in between in order to prevent loading whole response in memory
AVOID unnecessary FFI calls as their cost is non zero
AVOID unnecessary strings transformations - replace them with more efficient alternatives if possible
AVOID cryptic names - prefer short but concise names (wr is BAD, full_write is GOOD)
FOCUS on code readability: extract helper functions if it will contribute to the code readability (do not overoptimize - it's fine to have some logic inlined especially if it is not repeated anywhere else)
WATCH OUT for variables scopes and do not use variables which are no longer accessible

Implementation

Annotate public API with types
Add comments about public API fields/functions to clarify meaning and usage scenarios
Use turso_sync_database_create() method for creation of the synced database for now - DO NOT use init + open pair

Bindings

You must use bindings in the bindings_sync.go and intergrate with driver_db.go code (use NewConnection function for that) Inspect bindings_db.go as you will reuse some abstractions from there.