Files
music_library/lib/music_library_web/components/chart_components.ex
T
Claudio Ortolina 14d0343f34 Make charts smaller
2025-08-31 09:47:41 +03:00

102 lines
3.0 KiB
Elixir

defmodule MusicLibraryWeb.ChartComponents do
use MusicLibraryWeb, :live_component
@doc """
Renders a horizontal bar chart.
## Examples
<.vertical_bar_chart
data={[{"Artist 1", 5}, {"Artist 2", 3}]}
label_fn={&elem(&1, 0)}
value_fn={&elem(&1, 1)}
width={400}
height={300}
color_class="fill-red-500"
/>
"""
attr :data, :list, required: true
attr :label_fn, :any, required: true
attr :value_fn, :any, required: true
attr :width, :integer, default: 400
attr :height, :integer, default: 300
attr :color_class, :string, required: true
attr :class, :string, default: ""
attr :label_click, :any, default: nil, doc: "the function for handling phx-click on each label"
def vertical_bar_chart(assigns) do
assigns =
assigns
|> assign(:padding, 40)
|> assign(:max_value, max_value(assigns.data, assigns.value_fn))
# Account for labels and padding
|> assign(:chart_width, assigns.width - 150 - 40)
# Account for bottom padding
|> assign(:chart_height, assigns.height - 40)
|> assign(:bar_height, calculate_bar_height(assigns.data, assigns.height - 40))
~H"""
<div class={["w-full", @class]}>
<svg
viewBox={"0 0 #{@width} #{@height}"}
preserveAspectRatio="xMidYMid meet"
class="w-full h-full"
>
<%!-- Bars and labels --%>
<%= for {datum, index} <- Enum.with_index(@data) do %>
<% bar_width = @chart_width * @value_fn.(datum) / @max_value %>
<% y = @padding / 2 + index * (@bar_height + 4) %>
<%!-- Label --%>
<text
x="140"
y={y + @bar_height / 2 + 4}
text-anchor="end"
class={["text-xs fill-zinc-500 dark:fill-zinc-400", @label_click && "cursor-pointer"]}
phx-click={@label_click && @label_click.(datum)}
>
{truncate_label(@label_fn.(datum), 20)}
</text>
<%!-- Bar --%>
<rect
x="150"
y={y}
width={bar_width}
height={@bar_height}
class={["opacity-80 hover:opacity-100 transition-opacity", @color_class]}
>
<title>{@label_fn.(datum)}: {@value_fn.(datum)}</title>
</rect>
<%!-- Value label --%>
<text
x={150 + bar_width + 5}
y={y + @bar_height / 2 + 4}
class="text-xs fill-zinc-500 dark:fill-zinc-400"
>
{@value_fn.(datum)}
</text>
<% end %>
</svg>
</div>
"""
end
defp max_value(data, value_fn) do
max = Enum.max_by(data, value_fn)
value_fn.(max)
end
defp calculate_bar_height(data, available_height) do
bar_count = length(data)
max_height = min(15, (available_height - (bar_count - 1) * 4) / bar_count)
max(20, max_height) |> trunc()
end
defp truncate_label(label, max_length) when byte_size(label) > max_length do
String.slice(label, 0, max_length - 2) <> ".."
end
defp truncate_label(label, _), do: label
end