Documentation
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Overview ¶
Package layout computes the TUI 2.0 frame's region budget: how many cells wide each column is, how many rows the body gets, and which chrome rows are shown at all.
It is deliberately pure arithmetic over (width, height, rail preference) — no styling, no components, no I/O — so the responsive rules can be tested exhaustively and the goldens in docs/fixtures can be checked against them without rendering anything.
The rules are docs/tui-2.0.md, "Frame and responsive layout", and were confirmed against the golden fixtures at 80x24, 100x30, 120x40, 137x29, and 200x60.
Index ¶
Constants ¶
const ( // ChatListWide is the chat list's width when there is room for it. ChatListWide = 38 // ChatListNarrow is the reduced width used before dropping to a single // panel. Giving up 8 cells here buys the thread 8. ChatListNarrow = 30 // RailWidth is the context rail's width when shown. RailWidth = 30 // RuleWidth is the one-cell vertical rule between two regions. RuleWidth = 1 // InlineComposerHeight is the composer's default single row. InlineComposerHeight = 1 // MaxContextRows is how much a short terminal will spend above the // prompt on saying what it is for: a reply quote, or an attachment // chip. One, because past that the thread stops being readable and the // composer knows to shed the rest itself. MaxContextRows = 1 )
Fixed region widths, in cells. The chat list and rail are fixed rather than proportional because they hold columnar data whose budget is designed (a 38-cell chat row, a 30-cell rail row), while the thread is the region that should absorb whatever is left.
const ( // MinRailWidth is the narrowest terminal that still shows the rail: // 38 + 1 + 48 + 1 + 30. Below it the thread would be squeezed harder // than the rail is worth. MinRailWidth = 118 // MinWideListWidth is the narrowest terminal that keeps the chat list // at its full width. MinWideListWidth = 90 // MinTwoPanelWidth is the narrowest terminal that shows two panels at // all. Below it, one panel owns the screen and Tab swaps them. MinTwoPanelWidth = 72 )
Width thresholds. See Compute for the precedence these encode.
const ( // MinFullHeight is the shortest terminal that renders the whole frame, // hint bar included. MinFullHeight = 20 // MinTopBarHeight is the shortest terminal that keeps the top bar. Below // it only the thread and its inline composer are drawn. MinTopBarHeight = 12 )
Height thresholds.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Layout ¶
type Layout struct {
Width, Height int
// ChatListWidth, ThreadWidth, and RailWidth are the three columns.
// Exactly one RuleWidth separates each pair of adjacent non-zero
// regions, and the three plus their rules always sum to Width.
ChatListWidth int
ThreadWidth int
RailWidth int
// TopBar and HintBar report whether those single chrome rows are drawn.
TopBar bool
HintBar bool
// BodyHeight is the rows between the chrome bars — everything the
// columns get to divide up.
BodyHeight int
// ChatListHeight is the rows the chat list column gets: the whole body,
// since its filter header and footer are drawn inside that budget.
ChatListHeight int
// ComposerHeight is the rows reserved at the foot of the THREAD column
// (not the chat list — the golden frames put the chat list's own footer
// beside the composer, not above it). One row inline; the eight-row
// expanded form is refused when InlineComposerOnly is set.
ComposerHeight int
// ThreadHeight is what is left of the body for the thread's header and
// scroller once the composer has taken its rows.
ThreadHeight int
// SinglePanel means the terminal is too narrow for two columns: one
// panel owns the full width and Tab swaps which.
SinglePanel bool
// InlineComposerOnly means the composer may not expand to its eight-row
// form, because there are not enough rows to give it.
InlineComposerOnly bool
}
Layout is the computed frame budget. Every width is in cells and every height in rows; a zero width means the region is not drawn at all.
func Compute ¶
Compute returns the frame budget for a terminal of the given size.
Width precedence — the thread is the region that must survive, so the order in which space is given up is: the rail first, then the chat list's extra 8 cells, then the second column entirely.
>= 118 38 / rule / flex / rule / 30 90..117 38 / rule / flex 72..89 30 / rule / flex < 72 one panel, full width
railEnabled is the user's explicit preference (ui.rail / the grave-accent toggle). Width can force the rail off, but never on: a user who turned it off does not get it back by widening the terminal.
Height precedence:
>= 20 full frame 12..19 top bar kept, hint bar dropped, composer forced inline < 12 thread and its inline composer only
func (Layout) TotalWidth ¶
TotalWidth returns what the regions and their rules actually sum to. It exists so tests and the frame assembler can assert the invariant directly rather than re-deriving it: if this ever differs from Layout.Width, some row is going to be the wrong length and the frame will shear.
Source Files