WIP components (as built)

file_grid.go

@@ -0,0 +1,129 @@
+package mujica
+
+import (
+	"log/slog"
+
+	"github.com/egoist/mygo/ui"
+
+	"mujicaui/theme"
+)
+
+// FileGridOptions configure a FileGrid.
+type FileGridOptions struct {
+	// Revision changes when entries are edited in place.
+	Revision uint64
+	// Thumbnail builds a preview; nil or false shows FileIcon.
+	Thumbnail func(e FileEntry) bool
+	// ItemWidth defaults to 128 DIP, minimum 28.
+	ItemWidth float32
+	Disabled  bool
+}
+
+// FileGridResult is a FileGrid and what happened in this frame.
+type FileGridResult struct {
+	Element *ui.Element
+	// Changed reports a new selection; Opened is the entry opened.
+	Changed bool
+	Opened  *FileEntry
+}
+
+// FileGridState is a FileGrid's selection and place.
+type FileGridState struct {
+	list     ListState[string]
+	data     *FileEntry
+	n        int
+	revision uint64
+	paths    []string
+}
+
+// Selected returns the chosen entries' paths.
+func (s *FileGridState) Selected() []string {
+	var out []string
+	for p := range s.list.Selection.All() {
+		out = append(out, p)
+	}
+	return out
+}
+
+// FileGrid virtualizes thumbnails, file selection and opening.
+func FileGrid(c *ui.Context, entries []FileEntry, s *FileGridState, opts FileGridOptions) FileGridResult {
+	if s == nil {
+		panic("mujica: FileGrid needs a state")
+	}
+	if opts.ItemWidth < 0 {
+		panic("mujica: FileGrid ItemWidth is negative")
+	}
+	w := opts.ItemWidth
+	if w == 0 {
+		w = 128
+	}
+	k := Tokens(c)
+	u := Density(c).Unit()
+	if w < theme.MinHitSize {
+		panic("mujica: FileGrid ItemWidth is below the minimum hit size")
+	}
+	thumb := max(0, w-4*u)
+	var res FileGridResult
+	res.Element = ui.Column(c).MinHeight(0).Disabled(opts.Disabled)
+	disabled := res.Element.IsDisabled()
+	if disabled {
+		copy := *s
+		copy.list.Selection = filesSelectionCopy(s.list.Selection)
+		s = &copy
+	}
+	var first *FileEntry
+	if len(entries) > 0 {
+		first = &entries[0]
+	}
+	if s.data != first || s.n != len(entries) || s.revision != opts.Revision {
+		valid := make(map[string]bool, len(entries))
+		moved := len(s.paths) != len(entries)
+		for i, entry := range entries {
+			if entry.Path == "" || valid[entry.Path] {
+				panic("mujica: FileGrid needs unique entry paths")
+			}
+			valid[entry.Path] = true
+			if i >= len(s.paths) || s.paths[i] != entry.Path {
+				moved = true
+			}
+		}
+		for key := range s.list.Selection.All() {
+			if !valid[key] {
+				s.list.Selection.Remove(key)
+			}
+		}
+		if moved {
+			s.list.grid = ui.GridState{}
+			s.paths = make([]string, len(entries))
+			for i, entry := range entries {
+				s.paths[i] = entry.Path
+			}
+		}
+		s.data, s.n, s.revision = first, len(entries), opts.Revision
+	}
+	res.Element.Children(func() {
+		v := List(c, &s.list, len(entries), ListOptions[string]{Multiple: true, Grid: true, ItemWidth: w, ItemHeight: thumb*0.75 + 56,
+			Key: func(i int) string { return entries[i].Path }, Label: func(i int) string { return entries[i].Name },
+			Empty: msg(c, "file_grid.empty")}, func(i int) {
+			e := entries[i]
+			ui.Box(c).Height(thumb * 0.75).Shrink(0).Center().Clip().Radius(theme.ControlRadius).Background(k.Background).Children(func() {
+				if opts.Thumbnail == nil || !opts.Thumbnail(e) {
+					FileIcon(c, e.Name, FileIconOptions{Folder: e.Dir, Size: 40})
+				}
+			})
+			ui.Text(c, e.Name).SingleLine().TextAlign(ui.Center).FontSize(FontSize(c, theme.CaptionSize))
+		})
+		v.Element.Grow(1)
+		res.Changed = v.Changed() && !disabled
+		if key, ok := s.list.Selected(); ok && v.Submitted() && !res.Element.IsDisabled() {
+			for _, e := range entries {
+				if e.Path == key {
+					open := e
+					res.Opened = &open
+					slog.Debug("mujica: file_grid open", "dir", e.Dir)
+				}
+			}
+		}
+	})
+	return res
+}