trueno 0.18.0

//! Coverage tests for `ExecutionGraph::slowest_kernel` (core.rs:291)
//! and `ExecutionGraph::to_csr` (export.rs:247, gated by `execution-graph` feature).

use super::super::*;

// ========================================================================
// slowest_kernel tests — exercises all branches (18 uncovered lines)
// ========================================================================

/// Empty graph returns None.
#[test]
fn test_slowest_kernel_empty_graph() {
    let graph = ExecutionGraph::new();
    assert!(graph.slowest_kernel().is_none());
}

/// Graph with only layers (no bricks) returns None.
#[test]
fn test_slowest_kernel_no_bricks() {
    let mut graph = ExecutionGraph::new();
    graph.add_node(ExecutionNode::Layer { index: 0 });
    graph.add_node(ExecutionNode::Layer { index: 1 });
    assert!(graph.slowest_kernel().is_none());
}

/// Graph with bricks but no kernel launches returns None.
#[test]
fn test_slowest_kernel_bricks_without_kernel_launches() {
    let mut graph = ExecutionGraph::new();
    let layer = graph.add_node(ExecutionNode::Layer { index: 0 });
    let brick = graph.add_node(ExecutionNode::Brick {
        id: BrickId::RmsNorm,
        timing_ns: 5000,
        elements: 1024,
    });
    // Only Contains edge, no Launches edge
    graph.add_edge(layer, brick, EdgeType::Contains);
    assert!(graph.slowest_kernel().is_none());
}

/// Single brick with a kernel launch — should return that brick.
#[test]
fn test_slowest_kernel_single_brick_with_kernel() {
    let mut graph = ExecutionGraph::new();
    let brick = graph.add_node(ExecutionNode::Brick {
        id: BrickId::QkvProjection,
        timing_ns: 3000,
        elements: 2048,
    });
    let kernel = graph.add_node(ExecutionNode::Kernel {
        name: "gemv_kernel".into(),
        ptx_hash: 0xABCD,
        grid: (4, 1, 1),
        block: (128, 1, 1),
        shared_mem: 2048,
        timing_ns: None,
        arithmetic_intensity: None,
        achieved_tflops: None,
    });
    graph.add_edge(brick, kernel, EdgeType::Launches);

    let result = graph.slowest_kernel();
    assert!(result.is_some());
    let (id, node, timing) = result.unwrap();
    assert_eq!(id, brick);
    assert_eq!(timing, 3000);
    assert!(node.is_brick());
}

/// Multiple bricks with kernels — should return the slowest (highest timing_ns).
#[test]
fn test_slowest_kernel_multiple_bricks() {
    let mut graph = ExecutionGraph::new();

    // Fast brick (1000 ns)
    let brick_fast = graph.add_node(ExecutionNode::Brick {
        id: BrickId::RmsNorm,
        timing_ns: 1000,
        elements: 512,
    });
    let kernel_fast = graph.add_node(ExecutionNode::Kernel {
        name: "rmsnorm_kernel".into(),
        ptx_hash: 0x1111,
        grid: (1, 1, 1),
        block: (256, 1, 1),
        shared_mem: 0,
        timing_ns: None,
        arithmetic_intensity: None,
        achieved_tflops: None,
    });
    graph.add_edge(brick_fast, kernel_fast, EdgeType::Launches);

    // Slow brick (9000 ns) — should be selected
    let brick_slow = graph.add_node(ExecutionNode::Brick {
        id: BrickId::QkvProjection,
        timing_ns: 9000,
        elements: 4096,
    });
    let kernel_slow = graph.add_node(ExecutionNode::Kernel {
        name: "qkv_kernel".into(),
        ptx_hash: 0x2222,
        grid: (32, 1, 1),
        block: (256, 1, 1),
        shared_mem: 4096,
        timing_ns: None,
        arithmetic_intensity: None,
        achieved_tflops: None,
    });
    graph.add_edge(brick_slow, kernel_slow, EdgeType::Launches);

    // Medium brick (5000 ns)
    let brick_mid = graph.add_node(ExecutionNode::Brick {
        id: BrickId::AttentionScore,
        timing_ns: 5000,
        elements: 2048,
    });
    let kernel_mid = graph.add_node(ExecutionNode::Kernel {
        name: "attn_kernel".into(),
        ptx_hash: 0x3333,
        grid: (8, 1, 1),
        block: (128, 1, 1),
        shared_mem: 1024,
        timing_ns: None,
        arithmetic_intensity: None,
        achieved_tflops: None,
    });
    graph.add_edge(brick_mid, kernel_mid, EdgeType::Launches);

    let result = graph.slowest_kernel();
    assert!(result.is_some());
    let (id, _node, timing) = result.unwrap();
    assert_eq!(id, brick_slow);
    assert_eq!(timing, 9000);
}

/// Mix of bricks with and without kernel launches — only those with Launches count.
#[test]
fn test_slowest_kernel_mixed_bricks() {
    let mut graph = ExecutionGraph::new();

    // Brick WITHOUT kernel launch (very high timing, but should be ignored)
    let brick_no_launch = graph.add_node(ExecutionNode::Brick {
        id: BrickId::Embedding,
        timing_ns: 99999,
        elements: 8192,
    });
    // Only Contains edge, no Launches
    let layer = graph.add_node(ExecutionNode::Layer { index: 0 });
    graph.add_edge(layer, brick_no_launch, EdgeType::Contains);

    // Brick WITH kernel launch (lower timing but is the only candidate)
    let brick_with_launch = graph.add_node(ExecutionNode::Brick {
        id: BrickId::GateProjection,
        timing_ns: 2000,
        elements: 1024,
    });
    let kernel = graph.add_node(ExecutionNode::Kernel {
        name: "gate_kernel".into(),
        ptx_hash: 0x4444,
        grid: (2, 1, 1),
        block: (64, 1, 1),
        shared_mem: 512,
        timing_ns: None,
        arithmetic_intensity: None,
        achieved_tflops: None,
    });
    graph.add_edge(brick_with_launch, kernel, EdgeType::Launches);

    let result = graph.slowest_kernel();
    assert!(result.is_some());
    let (id, _node, timing) = result.unwrap();
    assert_eq!(id, brick_with_launch);
    assert_eq!(timing, 2000);
}

/// Equal timing — first encountered wins (stable ordering).
#[test]
fn test_slowest_kernel_equal_timing() {
    let mut graph = ExecutionGraph::new();

    let brick_a = graph.add_node(ExecutionNode::Brick {
        id: BrickId::RmsNorm,
        timing_ns: 5000,
        elements: 256,
    });
    let kernel_a = graph.add_node(ExecutionNode::Kernel {
        name: "kernel_a".into(),
        ptx_hash: 0xAAAA,
        grid: (1, 1, 1),
        block: (32, 1, 1),
        shared_mem: 0,
        timing_ns: None,
        arithmetic_intensity: None,
        achieved_tflops: None,
    });
    graph.add_edge(brick_a, kernel_a, EdgeType::Launches);

    let brick_b = graph.add_node(ExecutionNode::Brick {
        id: BrickId::LayerNorm,
        timing_ns: 5000,
        elements: 256,
    });
    let kernel_b = graph.add_node(ExecutionNode::Kernel {
        name: "kernel_b".into(),
        ptx_hash: 0xBBBB,
        grid: (1, 1, 1),
        block: (32, 1, 1),
        shared_mem: 0,
        timing_ns: None,
        arithmetic_intensity: None,
        achieved_tflops: None,
    });
    graph.add_edge(brick_b, kernel_b, EdgeType::Launches);

    let result = graph.slowest_kernel();
    assert!(result.is_some());
    let (_id, _node, timing) = result.unwrap();
    // Both have 5000 — equal timing so first brick wins (Some(_) branch)
    assert_eq!(timing, 5000);
}

/// Brick with zero timing still counts if it has a kernel launch.
#[test]
fn test_slowest_kernel_zero_timing() {
    let mut graph = ExecutionGraph::new();

    let brick =
        graph.add_node(ExecutionNode::Brick { id: BrickId::Sampling, timing_ns: 0, elements: 1 });
    let kernel = graph.add_node(ExecutionNode::Kernel {
        name: "sample_kernel".into(),
        ptx_hash: 0x0,
        grid: (1, 1, 1),
        block: (1, 1, 1),
        shared_mem: 0,
        timing_ns: None,
        arithmetic_intensity: None,
        achieved_tflops: None,
    });
    graph.add_edge(brick, kernel, EdgeType::Launches);

    let result = graph.slowest_kernel();
    assert!(result.is_some());
    let (_id, _node, timing) = result.unwrap();
    assert_eq!(timing, 0);
}

// ========================================================================
// ExecutionGraph helper coverage
// ========================================================================

/// Test kernel_nodes iterator.
#[test]
fn test_kernel_nodes_iterator() {
    let mut graph = ExecutionGraph::new();
    graph.add_node(ExecutionNode::Layer { index: 0 });
    graph.add_node(ExecutionNode::Brick { id: BrickId::RmsNorm, timing_ns: 100, elements: 64 });
    graph.add_node(ExecutionNode::Kernel {
        name: "k1".into(),
        ptx_hash: 0,
        grid: (1, 1, 1),
        block: (32, 1, 1),
        shared_mem: 0,
        timing_ns: None,
        arithmetic_intensity: None,
        achieved_tflops: None,
    });
    graph.add_node(ExecutionNode::Kernel {
        name: "k2".into(),
        ptx_hash: 1,
        grid: (2, 1, 1),
        block: (64, 1, 1),
        shared_mem: 128,
        timing_ns: Some(500),
        arithmetic_intensity: Some(1.5),
        achieved_tflops: Some(0.2),
    });

    let kernels: Vec<_> = graph.kernel_nodes().collect();
    assert_eq!(kernels.len(), 2);
    assert!(kernels[0].1.is_kernel());
    assert!(kernels[1].1.is_kernel());
}

/// Test node_by_name lookup.
#[test]
fn test_node_by_name() {
    let mut graph = ExecutionGraph::new();
    graph.add_node(ExecutionNode::Kernel {
        name: "my_kernel".into(),
        ptx_hash: 42,
        grid: (1, 1, 1),
        block: (256, 1, 1),
        shared_mem: 0,
        timing_ns: None,
        arithmetic_intensity: None,
        achieved_tflops: None,
    });

    let found = graph.node_by_name("my_kernel");
    assert!(found.is_some());
    let (id, node) = found.unwrap();
    assert_eq!(id, ExecutionNodeId(0));
    assert!(node.is_kernel());

    // Non-existent name
    assert!(graph.node_by_name("nonexistent").is_none());
}

/// Test record_kernel_launch_with_metrics (Phase 9 roofline).
#[test]
fn test_record_kernel_launch_with_metrics() {
    let mut graph = ExecutionGraph::new();
    let scope = graph.push_scope(ExecutionNode::Layer { index: 0 });

    let kernel_id = graph.record_kernel_launch_with_metrics(
        "matmul_tiled",
        0xDEAD,
        (16, 1, 1),
        (256, 1, 1),
        8192,
        1500, // timing_ns
        4.5,  // arithmetic_intensity
        1.2,  // achieved_tflops
    );

    graph.pop_scope();

    let kernel = graph.node(kernel_id).unwrap();
    assert!(kernel.is_kernel());
    assert_eq!(kernel.timing_ns(), Some(1500));
    assert!((kernel.arithmetic_intensity().unwrap() - 4.5).abs() < 1e-5);
    assert!((kernel.achieved_tflops().unwrap() - 1.2).abs() < 1e-5);

    // Should have a Launches edge from scope to kernel
    let edges: Vec<_> = graph.outgoing_edges(scope).collect();
    assert!(edges.iter().any(|e| e.dst == kernel_id && e.edge_type == EdgeType::Launches));
}

/// Test record_transfer.
#[test]
fn test_record_transfer_in_scope() {
    let mut graph = ExecutionGraph::new();
    let scope = graph.push_scope(ExecutionNode::Layer { index: 0 });

    let transfer_id =
        graph.record_transfer("host", "gpu0", 1_048_576, TransferDirection::H2D, Some(250));

    graph.pop_scope();

    let node = graph.node(transfer_id).unwrap();
    assert!(node.is_transfer());
    assert_eq!(node.transfer_bytes(), Some(1_048_576));
    assert_eq!(node.timing_ns(), Some(250));

    // Should have Contains edge from scope
    let edges: Vec<_> = graph.outgoing_edges(scope).collect();
    assert!(edges.iter().any(|e| e.dst == transfer_id && e.edge_type == EdgeType::Contains));
}

/// Test add_dependency (DependsOn edge).
#[test]
fn test_add_dependency() {
    let mut graph = ExecutionGraph::new();
    let n0 = graph.add_node(ExecutionNode::Layer { index: 0 });
    let n1 = graph.add_node(ExecutionNode::Layer { index: 1 });

    graph.add_dependency(n0, n1);

    let edges: Vec<_> = graph.outgoing_edges(n0).collect();
    assert_eq!(edges.len(), 1);
    assert_eq!(edges[0].edge_type, EdgeType::DependsOn);
    assert_eq!(edges[0].dst, n1);
}

/// Test incoming_edges.
#[test]
fn test_incoming_edges() {
    let mut graph = ExecutionGraph::new();
    let a = graph.add_node(ExecutionNode::Layer { index: 0 });
    let b = graph.add_node(ExecutionNode::Layer { index: 1 });
    let c = graph.add_node(ExecutionNode::Layer { index: 2 });

    graph.add_edge(a, c, EdgeType::Sequence);
    graph.add_edge(b, c, EdgeType::Sequence);

    let incoming: Vec<_> = graph.incoming_edges(c).collect();
    assert_eq!(incoming.len(), 2);
}

/// Test is_scope_balanced.
#[test]
fn test_scope_balanced() {
    let mut graph = ExecutionGraph::new();
    assert!(graph.is_scope_balanced());

    graph.push_scope(ExecutionNode::Layer { index: 0 });
    assert!(!graph.is_scope_balanced());

    graph.pop_scope();
    assert!(graph.is_scope_balanced());
}

/// Test add_weighted_edge.
#[test]
fn test_add_weighted_edge() {
    let mut graph = ExecutionGraph::new();
    let a = graph.add_node(ExecutionNode::Layer { index: 0 });
    let b = graph.add_node(ExecutionNode::Layer { index: 1 });

    graph.add_weighted_edge(a, b, EdgeType::Calls, 3.5);

    let edges: Vec<_> = graph.outgoing_edges(a).collect();
    assert_eq!(edges.len(), 1);
    assert!((edges[0].weight - 3.5).abs() < 1e-5);
}

// ========================================================================
// to_csr tests — gated by `execution-graph` feature (export.rs:257)
// ========================================================================

/// to_csr on empty graph produces an empty CsrGraph.
#[cfg(feature = "execution-graph")]
#[test]
fn test_to_csr_empty_graph() {
    let graph = ExecutionGraph::new();
    let csr = graph.to_csr();
    assert_eq!(csr.num_edges(), 0);
}

/// to_csr with single node and no edges.
#[cfg(feature = "execution-graph")]
#[test]
fn test_to_csr_single_node_no_edges() {
    let mut graph = ExecutionGraph::new();
    graph.add_node(ExecutionNode::Layer { index: 0 });

    let csr = graph.to_csr();
    // Single node but no edges
    assert_eq!(csr.num_edges(), 0);
}

/// to_csr preserves edge structure (edges map correctly).
#[cfg(feature = "execution-graph")]
#[test]
fn test_to_csr_with_edges() {
    let mut graph = ExecutionGraph::new();
    let layer = graph.add_node(ExecutionNode::Layer { index: 0 });
    let brick = graph.add_node(ExecutionNode::Brick {
        id: BrickId::RmsNorm,
        timing_ns: 5000,
        elements: 2048,
    });
    let kernel = graph.add_node(ExecutionNode::Kernel {
        name: "rmsnorm_kernel".into(),
        ptx_hash: 0xABCD,
        grid: (4, 1, 1),
        block: (128, 1, 1),
        shared_mem: 1024,
        timing_ns: None,
        arithmetic_intensity: None,
        achieved_tflops: None,
    });

    graph.add_edge(layer, brick, EdgeType::Contains);
    graph.add_edge(brick, kernel, EdgeType::Launches);

    let csr = graph.to_csr();
    // Should have 2 edges
    assert_eq!(csr.num_edges(), 2);
}

/// to_csr sets node names from ExecutionNode::name().
#[cfg(feature = "execution-graph")]
#[test]
fn test_to_csr_node_names() {
    use trueno_graph::NodeId;

    let mut graph = ExecutionGraph::new();
    graph.add_node(ExecutionNode::Layer { index: 0 });
    graph.add_node(ExecutionNode::Brick {
        id: BrickId::QkvProjection,
        timing_ns: 3000,
        elements: 1024,
    });
    graph.add_node(ExecutionNode::Kernel {
        name: "matmul_kernel".into(),
        ptx_hash: 0x1234,
        grid: (8, 1, 1),
        block: (256, 1, 1),
        shared_mem: 4096,
        timing_ns: Some(2000),
        arithmetic_intensity: Some(3.5),
        achieved_tflops: Some(1.0),
    });

    // Need edges for CsrGraph to include nodes
    let n0 = ExecutionNodeId(0);
    let n1 = ExecutionNodeId(1);
    let n2 = ExecutionNodeId(2);
    graph.add_edge(n0, n1, EdgeType::Contains);
    graph.add_edge(n1, n2, EdgeType::Launches);

    let csr = graph.to_csr();

    // Verify node names are set
    assert_eq!(csr.get_node_name(NodeId(0)), Some("Layer0"));
    assert_eq!(csr.get_node_name(NodeId(1)), Some("QkvProjection"));
    assert_eq!(csr.get_node_name(NodeId(2)), Some("matmul_kernel"));
}

/// to_csr with weighted edges preserves edge weights.
#[cfg(feature = "execution-graph")]
#[test]
fn test_to_csr_weighted_edges() {
    let mut graph = ExecutionGraph::new();
    let a = graph.add_node(ExecutionNode::Layer { index: 0 });
    let b = graph.add_node(ExecutionNode::Layer { index: 1 });

    graph.add_weighted_edge(a, b, EdgeType::Sequence, 7.5);

    let csr = graph.to_csr();
    assert_eq!(csr.num_edges(), 1);
}

/// to_csr with all node types (Transfer, Function, AsyncTask).
#[cfg(feature = "execution-graph")]
#[test]
fn test_to_csr_all_node_types() {
    let mut graph = ExecutionGraph::new();
    let layer = graph.add_node(ExecutionNode::Layer { index: 0 });
    let func = graph.add_node(ExecutionNode::Function {
        name: "forward".into(),
        file: Some("model.rs".into()),
        line: Some(42),
    });
    let transfer = graph.add_node(ExecutionNode::Transfer {
        src: "host".into(),
        dst: "gpu0".into(),
        bytes: 1_000_000,
        direction: TransferDirection::H2D,
        timing_ns: Some(500),
    });
    let async_task = graph.add_node(ExecutionNode::AsyncTask {
        name: "prefetch".into(),
        poll_count: 3,
        yield_count: 1,
        total_poll_ns: 2000,
    });

    graph.add_edge(layer, func, EdgeType::Contains);
    graph.add_edge(func, transfer, EdgeType::Sequence);
    graph.add_edge(func, async_task, EdgeType::Sequence);

    let csr = graph.to_csr();
    assert_eq!(csr.num_edges(), 3);
}

// ========================================================================
// to_tree_node tests — gated by `presentar-tui` feature (export.rs:280)
// Cover missing branches: Transfer without timing, AsyncTask with 0 polls,
// Function with partial file/line, single root, children traversal.
// ========================================================================

/// to_tree_node: single root produces that node directly (not wrapped).
#[cfg(feature = "presentar-tui")]
#[test]
fn test_to_tree_node_single_root_layer() {
    let mut graph = ExecutionGraph::new();
    graph.add_node(ExecutionNode::Layer { index: 3 });
    let tree = graph.to_tree_node();
    assert_eq!(tree.label, "Layer 3");
    assert!(tree.children.is_empty());
}

/// to_tree_node: Transfer node with timing_ns = None (cover the unwrap_or_default branch).
#[cfg(feature = "presentar-tui")]
#[test]
fn test_to_tree_node_transfer_no_timing() {
    let mut graph = ExecutionGraph::new();
    let root = graph.add_node(ExecutionNode::Layer { index: 0 });
    let transfer = graph.add_node(ExecutionNode::Transfer {
        src: "gpu0".into(),
        dst: "host".into(),
        bytes: 4096,
        direction: TransferDirection::D2H,
        timing_ns: None,
    });
    graph.add_edge(root, transfer, EdgeType::Contains);

    let tree = graph.to_tree_node();
    assert_eq!(tree.label, "Layer 0");
    assert_eq!(tree.children.len(), 1);

    let transfer_node = &tree.children[0];
    // Transfer label should contain D2H direction
    assert!(
        transfer_node.label.contains("D2H"),
        "Transfer label should contain direction: {}",
        transfer_node.label
    );
    // Info should show bytes but no timing
    let info = transfer_node.info.as_ref().expect("Transfer should have info");
    assert!(info.contains("4096B"), "Info should contain byte count: {}", info);
    // No timing means no µs suffix
    assert!(!info.contains("µs"), "No timing should mean no µs in info: {}", info);
}

/// to_tree_node: Transfer node with timing_ns = Some (cover timing branch).
#[cfg(feature = "presentar-tui")]
#[test]
fn test_to_tree_node_transfer_with_timing() {
    let mut graph = ExecutionGraph::new();
    let root = graph.add_node(ExecutionNode::Layer { index: 0 });
    let transfer = graph.add_node(ExecutionNode::Transfer {
        src: "host".into(),
        dst: "gpu0".into(),
        bytes: 1_048_576,
        direction: TransferDirection::H2D,
        timing_ns: Some(5000),
    });
    graph.add_edge(root, transfer, EdgeType::Contains);

    let tree = graph.to_tree_node();
    let transfer_node = &tree.children[0];
    let info = transfer_node.info.as_ref().expect("Transfer should have info");
    assert!(info.contains("µs"), "Timing present should include µs: {}", info);
    assert!(info.contains("1048576B"), "Info should contain byte count: {}", info);
}

/// to_tree_node: AsyncTask with poll_count = 0 (cover 0% efficiency branch).
#[cfg(feature = "presentar-tui")]
#[test]
fn test_to_tree_node_async_task_zero_polls() {
    let mut graph = ExecutionGraph::new();
    let root = graph.add_node(ExecutionNode::Layer { index: 0 });
    let async_node = graph.add_node(ExecutionNode::AsyncTask {
        name: "idle_task".into(),
        poll_count: 0,
        yield_count: 0,
        total_poll_ns: 0,
    });
    graph.add_edge(root, async_node, EdgeType::Contains);

    let tree = graph.to_tree_node();
    let async_child = &tree.children[0];
    assert_eq!(async_child.label, "idle_task");
    let info = async_child.info.as_ref().expect("AsyncTask should have info");
    assert!(info.contains("polls:0"), "Should show 0 polls: {}", info);
    assert!(info.contains("0% eff"), "Should show 0% efficiency: {}", info);
}

/// to_tree_node: AsyncTask with nonzero polls (cover normal efficiency).
#[cfg(feature = "presentar-tui")]
#[test]
fn test_to_tree_node_async_task_nonzero_polls() {
    let mut graph = ExecutionGraph::new();
    let root = graph.add_node(ExecutionNode::Layer { index: 0 });
    let async_node = graph.add_node(ExecutionNode::AsyncTask {
        name: "worker".into(),
        poll_count: 4,
        yield_count: 2,
        total_poll_ns: 8000,
    });
    graph.add_edge(root, async_node, EdgeType::Contains);

    let tree = graph.to_tree_node();
    let async_child = &tree.children[0];
    assert_eq!(async_child.label, "worker");
    let info = async_child.info.as_ref().expect("AsyncTask should have info");
    assert!(info.contains("polls:4"), "Should show poll count: {}", info);
    assert!(info.contains("yields:2"), "Should show yield count: {}", info);
    assert!(info.contains("25% eff"), "Should show 25% efficiency: {}", info);
}

/// to_tree_node: Function with file and line (cover Some/Some branch).
#[cfg(feature = "presentar-tui")]
#[test]
fn test_to_tree_node_function_with_location() {
    let mut graph = ExecutionGraph::new();
    let root = graph.add_node(ExecutionNode::Layer { index: 0 });
    let func = graph.add_node(ExecutionNode::Function {
        name: "forward_pass".into(),
        file: Some("model.rs".into()),
        line: Some(42),
    });
    graph.add_edge(root, func, EdgeType::Contains);

    let tree = graph.to_tree_node();
    let func_child = &tree.children[0];
    assert!(func_child.label.contains("forward_pass"), "Function label: {}", func_child.label);
    assert!(
        func_child.label.contains("model.rs:42"),
        "Function should include file:line: {}",
        func_child.label
    );
    // Function nodes have no info (None branch)
    assert!(func_child.info.is_none());
}

/// to_tree_node: Function with no file/line (cover None/None branch).
#[cfg(feature = "presentar-tui")]
#[test]
fn test_to_tree_node_function_no_location() {
    let mut graph = ExecutionGraph::new();
    let root = graph.add_node(ExecutionNode::Layer { index: 0 });
    let func =
        graph.add_node(ExecutionNode::Function { name: "dispatch".into(), file: None, line: None });
    graph.add_edge(root, func, EdgeType::Contains);

    let tree = graph.to_tree_node();
    let func_child = &tree.children[0];
    assert_eq!(func_child.label, "dispatch");
    assert!(func_child.info.is_none());
}

/// to_tree_node: Function with file but no line (cover Some/None branch).
#[cfg(feature = "presentar-tui")]
#[test]
fn test_to_tree_node_function_file_no_line() {
    let mut graph = ExecutionGraph::new();
    let root = graph.add_node(ExecutionNode::Layer { index: 0 });
    let func = graph.add_node(ExecutionNode::Function {
        name: "init".into(),
        file: Some("setup.rs".into()),
        line: None,
    });
    graph.add_edge(root, func, EdgeType::Contains);

    let tree = graph.to_tree_node();
    let func_child = &tree.children[0];
    // (Some(f), None) should result in empty location string
    assert_eq!(func_child.label, "init");
    assert!(!func_child.label.contains("setup.rs"));
}

/// to_tree_node: Function with no file but has line (cover None/Some branch).
#[cfg(feature = "presentar-tui")]
#[test]
fn test_to_tree_node_function_no_file_has_line() {
    let mut graph = ExecutionGraph::new();
    let root = graph.add_node(ExecutionNode::Layer { index: 0 });
    let func = graph.add_node(ExecutionNode::Function {
        name: "cleanup".into(),
        file: None,
        line: Some(99),
    });
    graph.add_edge(root, func, EdgeType::Contains);

    let tree = graph.to_tree_node();
    let func_child = &tree.children[0];
    // (None, Some) should result in empty location string
    assert_eq!(func_child.label, "cleanup");
}

/// to_tree_node: Brick node with info (cover Brick branch in build_node).
#[cfg(feature = "presentar-tui")]
#[test]
fn test_to_tree_node_brick_with_info() {
    let mut graph = ExecutionGraph::new();
    let root = graph.add_node(ExecutionNode::Layer { index: 0 });
    let brick = graph.add_node(ExecutionNode::Brick {
        id: BrickId::QkvProjection,
        timing_ns: 50_000,
        elements: 4096,
    });
    graph.add_edge(root, brick, EdgeType::Contains);

    let tree = graph.to_tree_node();
    let brick_child = &tree.children[0];
    assert_eq!(brick_child.label, "QkvProjection");
    let info = brick_child.info.as_ref().expect("Brick should have info");
    assert!(info.contains("50.0µs"), "Brick info should show timing: {}", info);
    assert!(info.contains("4096 elem"), "Brick info should show elements: {}", info);
}

/// to_tree_node: Kernel node with info (cover Kernel branch in build_node).
#[cfg(feature = "presentar-tui")]
#[test]
fn test_to_tree_node_kernel_with_info() {
    let mut graph = ExecutionGraph::new();
    let root = graph.add_node(ExecutionNode::Layer { index: 0 });
    let kernel = graph.add_node(ExecutionNode::Kernel {
        name: "gemm_tiled".into(),
        ptx_hash: 0xDEAD,
        grid: (16, 1, 1),
        block: (256, 1, 1),
        shared_mem: 8192,
        timing_ns: Some(1500),
        arithmetic_intensity: Some(4.0),
        achieved_tflops: Some(2.0),
    });
    graph.add_edge(root, kernel, EdgeType::Contains);

    let tree = graph.to_tree_node();
    let kernel_child = &tree.children[0];
    assert_eq!(kernel_child.label, "gemm_tiled");
    let info = kernel_child.info.as_ref().expect("Kernel should have info");
    assert!(info.contains("<<<16,256,1>>>"), "Kernel info should show launch config: {}", info);
    assert!(info.contains("smem=8192B"), "Kernel info should show shared mem: {}", info);
}

/// to_tree_node: D2D transfer direction (cover D2D direction variant).
#[cfg(feature = "presentar-tui")]
#[test]
fn test_to_tree_node_transfer_d2d() {
    let mut graph = ExecutionGraph::new();
    let root = graph.add_node(ExecutionNode::Layer { index: 0 });
    let transfer = graph.add_node(ExecutionNode::Transfer {
        src: "gpu0".into(),
        dst: "gpu1".into(),
        bytes: 2048,
        direction: TransferDirection::D2D,
        timing_ns: Some(300),
    });
    graph.add_edge(root, transfer, EdgeType::Contains);

    let tree = graph.to_tree_node();
    let transfer_child = &tree.children[0];
    assert!(
        transfer_child.label.contains("D2D"),
        "Transfer label should contain D2D: {}",
        transfer_child.label
    );
}

/// to_tree_node: multiple roots wraps in synthetic "Execution Graph" root.
#[cfg(feature = "presentar-tui")]
#[test]
fn test_to_tree_node_three_roots_synthetic() {
    let mut graph = ExecutionGraph::new();
    graph.add_node(ExecutionNode::Layer { index: 0 });
    graph.add_node(ExecutionNode::Layer { index: 1 });
    graph.add_node(ExecutionNode::Layer { index: 2 });

    let tree = graph.to_tree_node();
    assert_eq!(tree.label, "Execution Graph");
    assert_eq!(tree.children.len(), 3);
    assert_eq!(tree.children[0].label, "Layer 0");
    assert_eq!(tree.children[1].label, "Layer 1");
    assert_eq!(tree.children[2].label, "Layer 2");
}

/// to_tree_node: deep hierarchy with children traversal.
#[cfg(feature = "presentar-tui")]
#[test]
fn test_to_tree_node_deep_hierarchy_children() {
    let mut graph = ExecutionGraph::new();

    let layer = graph.add_node(ExecutionNode::Layer { index: 0 });
    let brick = graph.add_node(ExecutionNode::Brick {
        id: BrickId::RmsNorm,
        timing_ns: 10_000,
        elements: 512,
    });
    let kernel = graph.add_node(ExecutionNode::Kernel {
        name: "norm_kernel".into(),
        ptx_hash: 0xFF,
        grid: (2, 1, 1),
        block: (64, 1, 1),
        shared_mem: 256,
        timing_ns: None,
        arithmetic_intensity: None,
        achieved_tflops: None,
    });

    graph.add_edge(layer, brick, EdgeType::Contains);
    graph.add_edge(brick, kernel, EdgeType::Launches);

    let tree = graph.to_tree_node();
    assert_eq!(tree.label, "Layer 0");
    assert_eq!(tree.children.len(), 1);

    let brick_child = &tree.children[0];
    assert_eq!(brick_child.label, "RmsNorm");
    assert_eq!(brick_child.children.len(), 1);

    let kernel_child = &brick_child.children[0];
    assert_eq!(kernel_child.label, "norm_kernel");
    assert!(kernel_child.children.is_empty());
}