package layouts import "image" import "git.tebibyte.media/sashakoshka/tomo" import "git.tebibyte.media/sashakoshka/tomo/theme" // Vertical arranges elements vertically. Elements at the start of the entry // list will be positioned at the top, and elements at the end of the entry list // will positioned at the bottom. All elements have the same width. type Vertical struct { // If Gap is true, a gap will be placed between each element. Gap bool // If Pad is true, there will be padding running along the inside of the // layout's border. Pad bool } // Arrange arranges a list of entries vertically. func (layout Vertical) Arrange (entries []tomo.LayoutEntry, width, height int) { if layout.Pad { width -= theme.Padding() * 2 height -= theme.Padding() * 2 } freeSpace := height expandingElements := 0 // count the number of expanding elements and the amount of free space // for them to collectively occupy, while gathering minimum heights. minimumHeights := make([]int, len(entries)) for index, entry := range entries { var entryMinHeight int if child, flexible := entry.Element.(tomo.Flexible); flexible { entryMinHeight = child.FlexibleHeightFor(width) } else { _, entryMinHeight = entry.MinimumSize() } minimumHeights[index] = entryMinHeight if entry.Expand { expandingElements ++ } else { freeSpace -= entryMinHeight } if index > 0 && layout.Gap { freeSpace -= theme.Padding() } } expandingElementHeight := 0 if expandingElements > 0 { expandingElementHeight = freeSpace / expandingElements } x, y := 0, 0 if layout.Pad { x += theme.Padding() y += theme.Padding() } // set the size and position of each element for index, entry := range entries { if index > 0 && layout.Gap { y += theme.Padding() } entries[index].Position = image.Pt(x, y) entryHeight := 0 if entry.Expand { entryHeight = expandingElementHeight } else { entryHeight = minimumHeights[index] } y += entryHeight entryBounds := entry.Bounds() if entryBounds.Dx() != width || entryBounds.Dy() != entryHeight { entry.Resize(width, entryHeight) } } } // MinimumSize returns the minimum width and height that will be needed to // arrange the given list of entries. func (layout Vertical) MinimumSize ( entries []tomo.LayoutEntry, ) ( width, height int, ) { for index, entry := range entries { entryWidth, entryHeight := entry.MinimumSize() if entryWidth > width { width = entryWidth } height += entryHeight if layout.Gap && index > 0 { height += theme.Padding() } } if layout.Pad { width += theme.Padding() * 2 height += theme.Padding() * 2 } return } // FlexibleHeightFor Returns the minimum height the layout needs to lay out the // specified elements at the given width, taking into account flexible elements. func (layout Vertical) FlexibleHeightFor ( entries []tomo.LayoutEntry, width int, ) ( height int, ) { if layout.Pad { width -= theme.Padding() * 2 height += theme.Padding() * 2 } for index, entry := range entries { child, flexible := entry.Element.(tomo.Flexible) if flexible { height += child.FlexibleHeightFor(width) } else { _, entryHeight := entry.MinimumSize() height += entryHeight } if layout.Gap && index > 0 { height += theme.Padding() } } return }