///|
/// Renders a snapshot and highlights every audit finding in a self-contained SVG.
pub fn render_audit_svg(
  snapshot : LayoutSnapshot,
  report : AuditReport,
) -> String {
  let mut output = "\n"
}

///|
fn report_summary(report : AuditReport) -> String {
  "status=" +
  (if report.passed { "PASS" } else { "FAIL" }) +
  " overlaps=" +
  report.overlap_pairs.to_string() +
  " crossings=" +
  report.edge_crossings.to_string() +
  " out_of_bounds=" +
  report.out_of_bounds.to_string()
}

///|
fn edge_points_for_svg(
  snapshot : LayoutSnapshot,
  edge : Edge,
) -> (PositionedNode, PositionedNode)? {
  match
    (
      find_node_for_svg(snapshot.nodes, edge.source),
      find_node_for_svg(snapshot.nodes, edge.target),
    ) {
    (Some(source), Some(target)) => Some((source, target))
    _ => None
  }
}

///|
fn find_node_for_svg(
  nodes : Array[PositionedNode],
  id : String,
) -> PositionedNode? {
  for node in nodes {
    if node.id == id {
      return Some(node)
    }
  }
  None
}

///|
fn edge_key_for_svg(edge : Edge) -> String {
  edge.source + "->" + edge.target
}

///|
fn edge_has_violation(report : AuditReport, key : String) -> Bool {
  for violation in report.violations {
    if violation.kind == "edge_crossing" &&
      (violation.first == key || violation.second == key) {
      return true
    }
  }
  false
}

///|
fn node_has_violation(report : AuditReport, id : String) -> Bool {
  for violation in report.violations {
    if violation.first == id || violation.second == id {
      return true
    }
  }
  false
}

///|
fn node_left_for_svg(node : PositionedNode) -> Int {
  node.x - node.width / 2
}

///|
fn node_top_for_svg(node : PositionedNode) -> Int {
  node.y - node.height / 2
}

///|
fn escape_xml(input : String) -> String {
  input
  .replace_all(old="&", new="&")
  .replace_all(old="<", new="<")
  .replace_all(old=">", new=">")
  .replace_all(old="\"", new=""")
}