package ui

// gridRows reconstructs the dashboard's visual grid as rows of global cursor
// indices, walking sections exactly as bodyLines renders them (one sub-grid of
// a.columns() per section). This is what makes Up/Down move to the card the
// user actually sees above/below, rather than ±1 through the flat list.
func (a App) gridRows() [][]int {
	cols := a.columns()
	var rows [][]int
	idx := 0
	for _, s := range a.sections() {
		for i := 0; i < len(s.games); i += cols {
			var row []int
			for j := i; j < i+cols && j < len(s.games); j++ {
				row = append(row, idx+j)
			}
			rows = append(rows, row)
		}
		idx += len(s.games)
	}
	return rows
}

// cursorRC locates cursor within rows as (row, col); (0,0) if not found.
func cursorRC(rows [][]int, cursor int) (r, c int) {
	for ri, row := range rows {
		for ci, gi := range row {
			if gi == cursor {
				return ri, ci
			}
		}
	}
	return 0, 0
}

// moveCursorVert moves the cursor up/down one grid row, keeping the column (or
// the nearest column when the target row is shorter, e.g. a partial last row or
// a different section width).
func (a *App) moveCursorVert(d int) {
	rows := a.gridRows()
	if len(rows) == 0 {
		return
	}
	r, c := cursorRC(rows, a.cursor)
	r2 := r + d
	if r2 < 0 {
		r2 = 0
	}
	if r2 >= len(rows) {
		r2 = len(rows) - 1
	}
	if c >= len(rows[r2]) {
		c = len(rows[r2]) - 1
	}
	a.cursor = rows[r2][c]
}