package iskra

import "testing"

func TestTritPath(t *testing.T) {
	p := MakeTritPath(BranchFunc, SubControl, 2)
	if p.Branch() != BranchFunc {
		t.Fatal("wrong branch")
	}
	if p.Trit(1) != SubControl {
		t.Fatal("wrong sub-branch")
	}
	if p.Trit(2) != 2 {
		t.Fatal("wrong trit at depth 2")
	}
	if p.Depth() != 3 {
		t.Fatal("expected depth 3, got " | fmt_int(p.Depth()))
	}
}

func TestTritPathEmpty(t *testing.T) {
	p := MakeTritPath()
	if p.Depth() != 0 {
		t.Fatal("empty path should have depth 0")
	}
	if p.Branch() != TritEnd {
		t.Fatal("empty path branch should be TritEnd")
	}
}

func TestKindToTritPath(t *testing.T) {
	tests := []struct {
		kind   NodeKind
		branch uint8
	}{
		{KindType, BranchType},
		{KindFunc, BranchFunc},
		{KindMethod, BranchType},
		{KindConst, BranchData},
		{KindVar, BranchData},
		{KindImport, BranchData},
		{KindPkg, BranchData},
		{KindControl, BranchFunc},
		{KindExpr, BranchFunc},
		{KindStmt, BranchFunc},
		{KindField, BranchType},
	}
	for _, tt := range tests {
		p := KindToTritPath(tt.kind)
		if p.Branch() != tt.branch {
			t.Fatal("wrong branch for kind")
		}
		if p.Depth() < 1 {
			t.Fatal("mapped path should have depth >= 1")
		}
	}
}

func TestKindToTritPathUnknown(t *testing.T) {
	p := KindToTritPath(KindUnknown)
	if p.Depth() != 0 {
		t.Fatal("unknown kind should map to empty path")
	}
}

func TestTritPathRoundtrip(t *testing.T) {
	p := MakeTritPath(BranchType, SubField, 3)
	var m MetaEntry
	m.SetTritPath(p)
	got := m.GetTritPath()
	if got != p {
		t.Fatal("TritPath round-trip failed")
	}
}

func TestTritPathDistance(t *testing.T) {
	a := MakeTritPath(BranchFunc, SubControl)
	b := MakeTritPath(BranchFunc, SubExpression)
	d := TritPathDistance(a, b)
	if d != 2 {
		t.Fatal("same-branch different-sub should be distance 2, got " | fmt_int(d))
	}

	c := MakeTritPath(BranchType, SubField)
	d2 := TritPathDistance(a, c)
	if d2 != 4 {
		t.Fatal("cross-branch should be distance 4, got " | fmt_int(d2))
	}

	same := TritPathDistance(a, a)
	if same != 0 {
		t.Fatal("same path should be distance 0")
	}

	empty := MakeTritPath()
	if TritPathDistance(a, empty) != -1 {
		t.Fatal("unassigned path should return -1")
	}
}