import XCTest
@testable import MarkBase

final class G12BForwardTests: XCTestCase {
    
    func testModelInitialization() throws {
        print("\n═══════════════════════════════════════")
        print("      12B Model Initialization Test")
        print("═══════════════════════════════════════\n")
        
        let modelDir = "/Users/accusys/.cache/huggingface/hub/models--mlx-community--gemma-4-12B-it-4bit/snapshots/73bcf09092aa277861d5a191b989b666f7f32e8f"
        
        print("Step 1: Initialize Metal engine...")
        let engine = try MarkBaseEngine()
        try engine.compileSource(MetalKernels.combinedSource)
        print("  ✓ Engine ready\n")
        
        print("Step 2: Load 12B model...")
        
        // This will trigger the full shard loading
        do {
            let model = try E4BModel(modelDir: modelDir, engine: engine, maxContextLength: 512)
            
            print("  ✓ Model loaded successfully\n")
            
            print("Model parameters:")
            print("  Layers: \(model.numHiddenLayers)")
            print("  Hidden size: \(model.hiddenSize)")
            print("  Vocab size: \(model.vocabSize)")
            print("  KV shared layers: \(model.numKvShared)")
            
            // Verify 12B parameters
            XCTAssertEqual(model.numHiddenLayers, 48, "Should have 48 layers")
            XCTAssertEqual(model.hiddenSize, 3840, "Should have hidden_size=3840")
            XCTAssertEqual(model.numKvShared, 0, "Should have NO KV sharing")
            
            print("\n═══════════════════════════════════════")
            print("✓ Model initialization passed")
            print("═══════════════════════════════════════\n")
            
        } catch let error as E4BError {
            print("  ✗ Model loading failed (E4BError): \(error.localizedDescription)\n")
            throw error
        } catch let error as WeightError {
            print("  ✗ Model loading failed (WeightError): \(error.localizedDescription)\n")
            throw error
        } catch {
            print("  ✗ Model loading failed: \(error)\n")
            throw error
        }
    }
    
    func testForwardPassPlaceholder() throws {
        print("\n═══════════════════════════════════════")
        print("      Forward Pass Test (Placeholder)")
        print("═══════════════════════════════════════\n")
        
        print("This test will verify forward pass once full shard loading is implemented.\n")
        
        print("Expected steps:")
        print("  1. Load all shards (model-00001-of-00002 + model-00002-of-00002)")
        print("  2. Initialize 48-layer model")
        print("  3. Run forward pass for position 0")
        print("  4. Verify logits output [vocab_size=262144]")
        print("  5. Measure performance (expected ~0.08-0.12s/token)\n")
        
        print("Status: Pending full shard implementation\n")
    }
}