package core

// TextPos

type TextPos int32

// TextRange

type TextRange struct {
	pos TextPos
	end TextPos
}

func NewTextRange(pos int, end int) TextRange {
	return TextRange{pos: TextPos(pos), end: TextPos(end)}
}

func UndefinedTextRange() TextRange {
	return TextRange{pos: TextPos(-1), end: TextPos(-1)}
}

func (t TextRange) Pos() int {
	return int(t.pos)
}

func (t TextRange) End() int {
	return int(t.end)
}

func (t TextRange) Len() int {
	return int(t.end - t.pos)
}

func (t TextRange) IsValid() bool {
	return t.pos >= 0 || t.end >= 0
}

func (t TextRange) Contains(pos int) bool {
	return pos >= int(t.pos) && pos < int(t.end)
}

func (t TextRange) ContainsInclusive(pos int) bool {
	return pos >= int(t.pos) && pos <= int(t.end)
}

func (t TextRange) ContainsExclusive(pos int) bool {
	return int(t.pos) < pos && pos < int(t.end)
}

func (t TextRange) WithPos(pos int) TextRange {
	return TextRange{pos: TextPos(pos), end: t.end}
}

func (t TextRange) WithEnd(end int) TextRange {
	return TextRange{pos: t.pos, end: TextPos(end)}
}

func (t TextRange) ContainedBy(t2 TextRange) bool {
	return t2.pos <= t.pos && t2.end >= t.end
}

func (t TextRange) Overlaps(t2 TextRange) bool {
	start := max(t.pos, t2.pos)
	end := min(t.end, t2.end)
	return start < end
}

// Similar to Overlaps, but treats touching ranges as intersecting.
// For example, [0, 5) intersects [5, 10).
func (t TextRange) Intersects(t2 TextRange) bool {
	start := max(t.pos, t2.pos)
	end := min(t.end, t2.end)
	return start <= end
}

func CompareTextRanges(r1 TextRange, r2 TextRange) int {
	c := int(r1.pos) - int(r2.pos)
	if c != 0 {
		return c
	}
	return int(r1.end) - int(r2.end)
}