# `Harlock.Theme`
[🔗](https://github.com/thatsme/harlock/blob/v0.2.0/lib/harlock/theme.ex#L1)

Visual theme tokens used by the renderer.

v0.2 ships the minimum surface that the renderer actually reads today
so that widgets shipping in v0.3 (`progress`, `tabs`, `statusbar`,
`keybar`) aren't built against hard-coded values that need a sweep in
v0.4. The full theming ergonomics — extra tokens like `:primary` /
`:accent` / `:muted` / `:error`, built-in themes, truecolor downgrade —
arrive in v0.4.

Tokens (each a `Harlock.Render.Style.t()`):

  * `:header` — table column headers. Default: `bold: true`.
  * `:focus`  — active focus indicator. Default: `reverse: true`.
  * `:selection` — selected rows / cells. Default: `bg: :cyan`.
  * `:border` — default box border style. Default: `%Style{}` (no fg/bg).

## Setting a theme

    Harlock.run(MyApp, init_arg, theme: %Harlock.Theme{
      focus:     %Style{reverse: true, fg: :yellow},
      selection: %Style{bg: :blue, fg: :white}
    })

Omitting the option uses `Harlock.Theme.default/0`, which matches the
pre-theming hard-coded values byte-for-byte.

## Reading inside a callback

    def view(model) do
      accent = Harlock.Theme.get(:focus)
      text("hello", style: accent)
    end

The runtime stashes the theme in the process dictionary before
invoking `update/2` and `view/1`, mirroring the `Harlock.Focus` pattern.
Don't call `get/1` outside a Harlock callback — there's nothing in the
dictionary.

# `t`

```elixir
@type t() :: %Harlock.Theme{
  border: Harlock.Render.Style.t(),
  focus: Harlock.Render.Style.t(),
  header: Harlock.Render.Style.t(),
  selection: Harlock.Render.Style.t()
}
```

# `token`

```elixir
@type token() :: :header | :focus | :selection | :border
```

A theme is the bag of styled tokens the renderer looks up.

# `build`

```elixir
@spec build(keyword() | map() | t()) :: t()
```

Build a theme from a keyword list or a map. Unspecified tokens take
their default values.

# `default`

```elixir
@spec default() :: t()
```

The default theme. Matches the pre-theming hard-coded values exactly so
apps without a custom theme render byte-identically.

# `get`

```elixir
@spec get(token()) :: Harlock.Render.Style.t()
```

Look up a theme token. Returns the value from the theme installed by
the runtime, or the default if no theme is in scope.

---

*Consult [api-reference.md](api-reference.md) for complete listing*