@use '../tokens' as t;

// Value labels | plot, then the key labels under the plot. The grid is the container the label
// density is decided against — the plot's own width, not the viewport's.
.chart {
  @include t.container(line-chart);
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  grid-template-areas:
    'values box'
    '. keys';
  column-gap: t.space(2);
  row-gap: t.space(1);
  // The svg does not mirror in a right-to-left page, so the labels positioned over it must not
  // either: inline-start IS the svg's x = 0 here.
  direction: ltr;
}

.box {
  grid-area: box;
  position: relative;
  min-inline-size: 0;
}

.plot {
  display: block;
  inline-size: 100%;
  block-size: auto;
  overflow: visible;
}

.grid {
  stroke: t.role('line', 0.55);
  stroke-width: 1;
  stroke-dasharray: 2 4;
  // Hairlines stay hairlines however wide the chart is stretched.
  vector-effect: non-scaling-stroke;
}

.line {
  fill: none;
  stroke: var(--series);
  stroke-width: 2;
  stroke-linejoin: round;
  stroke-linecap: round;
  vector-effect: non-scaling-stroke;
}

.area {
  fill: var(--series);
  fill-opacity: 0.16;
  stroke: none;
}

.marker {
  fill: var(--series);
  // A ring of the surface around each marker keeps it legible where two lines cross.
  stroke: t.role('surface');
  stroke-width: 1;
  vector-effect: non-scaling-stroke;
}

// --- Labels: HTML text, so it keeps its type step at every chart width (issue 494) -----------

.tick,
.key {
  @include t.data-text;
  font-size: t.text(xs);
  line-height: t.leading(tight);
  color: t.role('fg-muted');
  white-space: nowrap;
}

// Every value label in one cell, each offset to its grid line: the column is as wide as the
// widest label and exactly as tall as the plot it stands beside.
.values {
  grid-area: values;
  display: grid;
}

.tick {
  grid-area: 1 / 1;
  align-self: start;
  justify-self: end;
  position: relative;
  inset-block-start: var(--at);
  translate: 0 -50%;
}

.keys {
  grid-area: keys;
  display: grid;
  min-inline-size: 0;
}

// Capped at a third of the axis: three labels on a stride of at least half the axis cannot meet.
.key {
  @include t.truncate;
  grid-area: 1 / 1;
  max-inline-size: calc(100% / 3);
}

.edge-start {
  justify-self: start;
  margin-inline-start: var(--at);
}

.edge-middle {
  justify-self: start;
  margin-inline-start: var(--at);
  translate: -50% 0;
}

.edge-end {
  justify-self: end;
  margin-inline-end: calc(100% - var(--at));
}

// Narrow first — a 390px phone: three key labels, every other value label.
.key[data-narrow='false'] {
  display: none;
}

.tick[data-minor='true'] {
  // `visibility`, never `display`: the column keeps the width of its widest label either way.
  visibility: hidden;
}

// A plot this wide holds six key labels (each capped at 2/15 of the axis: ⅔ of a fifth) and
// every value label.
@include t.container-query(line-chart, 36rem) {
  .key[data-narrow='false'] {
    display: block;
  }

  .key[data-wide='false'] {
    display: none;
  }

  .key {
    max-inline-size: calc(100% * 2 / 15);
  }

  .tick[data-minor='true'] {
    visibility: visible;
  }
}