use merman_core::diagrams::sequence::SequenceMessage;
use std::collections::BTreeMap;
pub(crate) fn sequence_activation_start_x(center_x: f64, stacked_size: usize, width: f64) -> f64 {
center_x + (((stacked_size as f64) - 1.0) * width) / 2.0
}
pub(crate) fn sequence_activation_stack_bounds(
depth: usize,
center_x: f64,
width: f64,
) -> (f64, f64) {
let mut left = center_x - 1.0;
let mut right = center_x + 1.0;
if depth == 0 {
return (left, right);
}
let first_start_x = sequence_activation_start_x(center_x, 0, width);
let last_start_x = sequence_activation_start_x(center_x, depth - 1, width);
left = left.min(first_start_x).min(last_start_x);
right = right.max(first_start_x + width).max(last_start_x + width);
(left, right)
}
pub(super) struct SequenceActivationState {
width: f64,
depths: BTreeMap<usize, usize>,
}
impl SequenceActivationState {
pub(super) fn new(width: f64) -> Self {
Self {
width,
depths: BTreeMap::new(),
}
}
pub(super) fn handle_directive(
&mut self,
msg: &SequenceMessage,
actor_index: &std::collections::HashMap<&str, usize>,
actor_centers_x: &[f64],
) -> bool {
match msg.message_type {
17 => {
let Some(actor_id) = msg.from.as_deref() else {
return true;
};
let Some(&idx) = actor_index.get(actor_id) else {
return true;
};
if actor_centers_x.get(idx).is_none() {
return true;
}
let depth = self.depths.entry(idx).or_default();
*depth = depth.saturating_add(1);
true
}
18 => {
let Some(actor_id) = msg.from.as_deref() else {
return true;
};
let Some(&idx) = actor_index.get(actor_id) else {
return true;
};
if let Some(depth) = self.depths.get_mut(&idx) {
*depth = depth.saturating_sub(1);
}
true
}
_ => false,
}
}
pub(super) fn actor_bounds(&self, actor_index: usize, center_x: f64) -> (f64, f64) {
sequence_activation_stack_bounds(
self.depths.get(&actor_index).copied().unwrap_or_default(),
center_x,
self.width,
)
}
pub(super) fn width(&self) -> f64 {
self.width
}
}
#[cfg(test)]
mod tests {
use super::{sequence_activation_stack_bounds, sequence_activation_start_x};
#[test]
fn activation_start_x_matches_mermaid_stack_offsets() {
assert_eq!(sequence_activation_start_x(100.0, 0, 10.0), 95.0);
assert_eq!(sequence_activation_start_x(100.0, 1, 10.0), 100.0);
assert_eq!(sequence_activation_start_x(100.0, 2, 10.0), 105.0);
}
#[test]
fn activation_stack_bounds_fold_full_active_stack() {
assert_eq!(
sequence_activation_stack_bounds(0, 100.0, 10.0),
(99.0, 101.0)
);
assert_eq!(
sequence_activation_stack_bounds(1, 100.0, 10.0),
(95.0, 105.0)
);
assert_eq!(
sequence_activation_stack_bounds(2, 100.0, 10.0),
(95.0, 110.0)
);
assert_eq!(
sequence_activation_stack_bounds(2, 100.0, -10.0),
(99.0, 101.0)
);
}
#[test]
fn activation_stack_bounds_only_need_progression_endpoints() {
assert_eq!(
sequence_activation_stack_bounds(10_000, 100.0, 10.0),
(95.0, 50_100.0)
);
}
}