package app

import (
	"strings"
	"unicode/utf8"

	"git.stormux.org/storm/cthulhu/internal/atspi"
	"git.stormux.org/storm/cthulhu/internal/braille"
	"git.stormux.org/storm/cthulhu/internal/config"
)

// Python includes context at the first line of text areas and omits desktop
// ancestry within web documents. Verbosity changes roles, not group labels.
func braille_context_frame(frame braille.Frame, snapshot atspi.Snapshot, options config.BrailleOptions) braille.Frame {
	if snapshot.Role == "terminal" || snapshot.TextCaretKnown && snapshot.BrailleLineStart > 0 {
		return frame
	}
	for _, ancestor := range snapshot.BrailleContext {
		if atspi.IsWebDocumentRole(ancestor.Role) {
			return frame
		}
	}
	parts := []string{}
	groupSkipped := false
	ancestors := snapshot.BrailleContext
	if len(ancestors) > 0 {
		switch ancestors[0].Role {
		case "menu", "menu bar", "page tab list", "redundant object", "unknown", "combo box":
			ancestors = ancestors[1:]
		}
	}
	for index := len(ancestors) - 1; index >= 0; index-- {
		ancestor := ancestors[index]
		if ancestor.ID().Valid() && ancestor.ID() == snapshot.ID() {
			continue
		}
		switch ancestor.Role {
		case "invalid", "unknown", "redundant object", "section", "split pane", "desktop frame", "scroll pane", "viewport":
			continue
		case "panel", "filler", "grouping":
			if strings.TrimSpace(ancestor.Name) == "" {
				continue
			}
			if snapshot.Role == "radio button" && ancestor.Name == snapshot.RadioGroupName && !groupSkipped {
				groupSkipped = true
				continue
			}
		}
		if ancestor.Role == "table" && ancestor.LayoutTable {
			continue
		}
		text := braille_object_frame(ancestor, options).Text
		if text != "" {
			parts = append(parts, text)
		}
	}
	parts = append(parts, snapshot.TableRowHeaders, snapshot.TableColumnHeaders, snapshot.RadioGroupName)
	prefix := brailleJoin(parts...)
	if prefix == "" {
		return frame
	}
	prefix += " "
	shift := utf8.RuneCountInString(prefix)
	frame.Text = prefix + frame.Text
	if frame.Cursor >= 0 {
		frame.Cursor += shift
	}
	if len(frame.Dots) != 0 {
		frame.Dots = append(make([]byte, shift), frame.Dots...)
	}
	for index := range frame.Routes {
		frame.Routes[index].Start += shift
		frame.Routes[index].End += shift
	}
	return frame
}