[Phase 3] Event Parser Optimization (Issue #40)

[gmajor-encrypt]

Summary

This PR implements an optimized Event parser for the SCALE codec library.

Features Implemented

EventRecord Parsing

• Phase support: ApplyExtrinsic, Finalization, Initialization
• Event data: Pallet index, event index, event data
• Topics: Vec<[u8; 32]> parsing

Components

Phase (enum)

• ApplyExtrinsic: Event from extrinsic execution
• Finalization: Event from block finalization
• Initialization: Event from block initialization

Event (class)

• Pallet name and index
• Event name and index
• Event data fields
• Field getters

EventRecord (class)

• Phase information
• Extrinsic index (for ApplyExtrinsic phase)
• Event data
• Topics list

EventParser (class)

• SCALE parsing for EventRecords
• Batch parsing support
• Metadata integration

EventIndex (class)

• Fast event lookup by name
• Fast event lookup by pallet
• Fast event lookup by extrinsic
• Phase-based filtering

ErrorEventDetector (class)

• Detect ExtrinsicFailed events
• Check if extrinsic failed
• Get error summary

Example Usage

use Substrate\ScaleCodec\Event\{EventParser, EventIndex, ErrorEventDetector};

// Parse events
$parser = new EventParser();
$events = $parser->parseHex($hexData);

// Index events for fast lookup
$index = new EventIndex($events);

// Find events by name
$transfers = $index->findByName('Balances', 'Transfer');

// Find events by extrinsic
$extrinsic0Events = $index->findByExtrinsic(0);

// Detect errors
$detector = new ErrorEventDetector($events);
if ($detector->hasErrors()) {
    $errors = $detector->getErrors();
}

Tests

• Unit tests in tests/Event/EventTest.php
• Phase tests
• EventRecord tests
• Parser tests
• Index tests
• Error detector tests

Issue

• Closes [Phase 3] Event Parser Optimization #40

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Ready for review.