yl_player_platform_interface v0.2

This package defines the immutable domain values, validators, and handwritten SPI used by endorsed yl_player implementations. It requires Dart 3.12 and Flutter 3.44. Applications should import package:yl_player/yl_player.dart; that barrel intentionally excludes registration, backend, transport, testing, and validation APIs.

A platform implementation subclasses YlPlayerPlatform, implements createPlayer(YlPlayerOptions), and returns a YlPlatformPlayer with validated initial state, capabilities, texture identity, and YlPlatformImplementationInfo(spiMajor: ylPlayerSpiMajor). Attach native callbacks before returning so no initial state or event can be lost.

assess is side-effect-free with respect to playback and returns compatible, incompatible, or requires-inspection. load returns YlPlatformLoadResult only after native commit and the correlated full state have both been accepted, in either order. It does not wait for Ready or First Frame. State revisions increase across sessions; every event carries the current session identity and revision. A replaced or stopped identity must reject commands. Command rejection must not fabricate state or events.

Session commands receive YlPlaybackSessionId. Volume, Stop, and Dispose are player-owned. Stop preserves a reusable player. Dispose is idempotent, terminates pending work, and releases resources even after failure. Public failures use validated YlFailure metadata and never forward raw native diagnostics.

Import package:yl_player_platform_interface/testing.dart for the reusable observable conformance utilities. The application-facing lifecycle is documented in the yl_player README; exact policy and diagnostic contracts are in the repository policy guide and diagnostics guide.