Refactoring : isolate stack manipulation into their own package

7 files changed, 195 insertions, 146 deletions

diff --git a/pkg/pointer/exec.go b/pkg/pointer/exec.go
index e2c55e3..8bb9dba 100644
--- a/pkg/pointer/exec.go
+++ b/pkg/pointer/exec.go
@@ -185,12 +185,7 @@ func (p *Pointer) eval(c int, f *field.Field) (done bool, returnValue *int) {
 		now := time.Now()
 		x, y, lx, ly := f.Dump()
 		const uintSize = 32 << (^uint(0) >> 32 & 1) // 32 or 64
-		heights := make([]int, p.ss.height)
-		s := p.ss.head
-		for i := p.ss.height - 1; i >= 0; i-- {
-			heights[i] = s.height
-			s = s.next
-		}
+		heights := p.ss.GetHeights()
 		// 20
 		for _, e := range os.Environ() {
 			vars := strings.SplitN(e, "=", 2)
@@ -255,14 +250,7 @@ func (p *Pointer) eval(c int, f *field.Field) (done bool, returnValue *int) {
 		// 1
 		p.ss.head.Push(0b00000) // TODO update when implementing t, i, o and =
 		if n > 0 {
-			if n > p.ss.head.height {
-				p.ss.head.height = 1
-				p.ss.head.data[0] = 0
-			} else {
-				v := p.ss.head.data[p.ss.head.height-n]
-				p.ss.head.height = heights[0]
-				p.ss.head.Push(v)
-			}
+			p.ss.YCommandPick(n, heights[0])
 		}
 	case '(':
 		n := p.ss.head.Pop()
diff --git a/pkg/pointer/stack-stack.go b/pkg/pointer/stack-stack.go
index 4bbfb73..9d4336a 100644
--- a/pkg/pointer/stack-stack.go
+++ b/pkg/pointer/stack-stack.go
@@ -1,13 +1,15 @@
 package pointer
 
+import "git.adyxax.org/adyxax/gofunge98/pkg/stack"
+
 type StackStack struct {
-	head   *Stack
+	head   *stack.Stack
 	height int
 }
 
 func NewStackStack() *StackStack {
 	return &StackStack{
-		head:   NewStack(),
+		head:   stack.NewStack(32, nil),
 		height: 1,
 	}
 }
@@ -20,24 +22,10 @@ func (ss *StackStack) Begin(p *Pointer) {
 	if np < 0 {
 		np = -np
 	}
-	toss := &Stack{
-		size: np,
-		data: make([]int, np),
-		next: soss,
-	}
+	toss := stack.NewStack(np, soss)
 	ss.head = toss
 	if n > 0 {
-		toss.height = n
-		elts := soss.height - n
-		if elts < 0 {
-			elts = soss.height
-		} else {
-			elts = n
-		}
-		for i := 1; i <= elts; i++ {
-			toss.data[toss.height-i] = soss.data[soss.height-i]
-		}
-		soss.height -= elts
+		toss.Transfert(soss, n)
 	} else if n < 0 {
 		for i := 0; i < np; i++ {
 			soss.Push(0)
@@ -53,31 +41,16 @@ func (ss *StackStack) End(p *Pointer) (reflect bool) {
 	if ss.height == 1 {
 		return true
 	}
-	soss := ss.head.next
+	toss := ss.head
+	soss := ss.head.Next()
 	n := ss.head.Pop()
 	y := soss.Pop()
 	x := soss.Pop()
 	p.SetStorageOffset(x, y)
 	if n > 0 {
-		if n > ss.head.height {
-			for i := n; i > ss.head.height; i-- {
-				soss.Push(0)
-			}
-			n = ss.head.height
-		}
-		soss.height += n
-		if soss.size < soss.height {
-			soss.data = append(soss.data, make([]int, soss.height-soss.size)...)
-			soss.size = soss.height
-		}
-		for i := n; i > 0; i-- {
-			soss.data[soss.height-i] = ss.head.data[ss.head.height-i]
-		}
+		soss.Transfert(toss, n)
 	} else if n < 0 {
-		soss.height += n
-		if soss.height < 0 {
-			soss.height = 0
-		}
+		soss.Discard(-n)
 	}
 	ss.height--
 	ss.head = soss
@@ -91,12 +64,16 @@ func (ss *StackStack) Under() (reflect bool) {
 	n := ss.head.Pop()
 	if n > 0 {
 		for i := 0; i < n; i++ {
-			ss.head.Push(ss.head.next.Pop())
+			ss.head.Push(ss.head.Next().Pop())
 		}
 	} else {
 		for i := 0; i < -n; i++ {
-			ss.head.next.Push(ss.head.Pop())
+			ss.head.Next().Push(ss.head.Pop())
 		}
 	}
 	return false
 }
+
+func (s StackStack) GetHeights() []int {
+	return s.head.GetHeights()
+}
diff --git a/pkg/pointer/stack-stack_test.go b/pkg/pointer/stack-stack_test.go
index dcb1960..959153d 100644
--- a/pkg/pointer/stack-stack_test.go
+++ b/pkg/pointer/stack-stack_test.go
@@ -5,15 +5,16 @@ import (
 	"testing"
 
 	"git.adyxax.org/adyxax/gofunge98/pkg/field"
+	"git.adyxax.org/adyxax/gofunge98/pkg/stack"
 	"github.com/stretchr/testify/require"
 )
 
 func TestBegin(t *testing.T) {
 	t.Run("empty", func(t *testing.T) {
 		expected := NewStackStack()
-		expected.head = &Stack{data: make([]int, 0), next: expected.head}
-		expected.head.next.Push(0)
-		expected.head.next.Push(0)
+		expected.head = stack.NewStack(0, expected.head)
+		expected.head.Next().Push(0)
+		expected.head.Next().Push(0)
 		expected.height++
 		p := NewPointer()
 		ss := p.ss
@@ -23,9 +24,9 @@ func TestBegin(t *testing.T) {
 		require.Equal(t, 1, x)
 		require.Equal(t, 0, y)
 		// Let's push another one
-		expected.head = &Stack{data: make([]int, 0), next: expected.head}
-		expected.head.next.Push(1)
-		expected.head.next.Push(0)
+		expected.head = stack.NewStack(0, expected.head)
+		expected.head.Next().Push(1)
+		expected.head.Next().Push(0)
 		expected.height++
 		ss.Begin(p)
 		require.Equal(t, expected, ss)
@@ -35,14 +36,14 @@ func TestBegin(t *testing.T) {
 	})
 	t.Run("negative", func(t *testing.T) {
 		expected := NewStackStack()
-		expected.head = &Stack{size: 5, height: 0, data: make([]int, 5), next: expected.head}
-		expected.head.next.Push(0)
-		expected.head.next.Push(0)
-		expected.head.next.Push(0)
-		expected.head.next.Push(0)
-		expected.head.next.Push(0)
-		expected.head.next.Push(0)
-		expected.head.next.Push(0)
+		expected.head = stack.NewStack(5, expected.head)
+		expected.head.Next().Push(0)
+		expected.head.Next().Push(0)
+		expected.head.Next().Push(0)
+		expected.head.Next().Push(0)
+		expected.head.Next().Push(0)
+		expected.head.Next().Push(0)
+		expected.head.Next().Push(0)
 		expected.height++
 		p := NewPointer()
 		file, err := os.Open("../field/test_data/hello.b98")
@@ -59,10 +60,13 @@ func TestBegin(t *testing.T) {
 	})
 	t.Run("ask to copy more than we have", func(t *testing.T) {
 		expected := NewStackStack()
-		expected.head = &Stack{size: 34, height: 34, data: make([]int, 34), next: expected.head}
-		expected.head.data[33] = 18
-		expected.head.next.Push(2)
-		expected.head.next.Push(3)
+		expected.head = stack.NewStack(34, expected.head)
+		for i := 0; i < 33; i++ {
+			expected.head.Push(0)
+		}
+		expected.head.Push(18)
+		expected.head.Next().Push(2)
+		expected.head.Next().Push(3)
 		expected.height++
 		p := NewPointer()
 		p.SetStorageOffset(2, 3)
@@ -81,16 +85,20 @@ func TestBegin(t *testing.T) {
 	})
 	t.Run("normal", func(t *testing.T) {
 		expected := NewStackStack()
-		expected.head = &Stack{size: 4, height: 4, data: []int{12, 14, -2, 5}, next: expected.head}
-		expected.head.next.Push(7)
-		expected.head.next.Push(36)
-		expected.head.next.Push(42)
-		expected.head.next.Push(-2)
-		expected.head.next.Push(5)
-		expected.head.next.Push(4)
-		expected.head.next.Pop()
-		expected.head.next.Pop()
-		expected.head.next.Pop()
+		expected.head = stack.NewStack(4, expected.head)
+		expected.head.Push(12)
+		expected.head.Push(14)
+		expected.head.Push(-2)
+		expected.head.Push(5)
+		expected.head.Next().Push(7)
+		expected.head.Next().Push(36)
+		expected.head.Next().Push(42)
+		expected.head.Next().Push(-2)
+		expected.head.Next().Push(5)
+		expected.head.Next().Push(4)
+		expected.head.Next().Pop()
+		expected.head.Next().Pop()
+		expected.head.Next().Pop()
 		expected.height++
 		p := NewPointer()
 		p.SetStorageOffset(36, 42)
@@ -162,8 +170,6 @@ func TestEnd(t *testing.T) {
 	})
 	t.Run("transfert", func(t *testing.T) {
 		expected := NewStackStack()
-		expected.head.size = 5
-		expected.head.data = make([]int, 5)
 		expected.head.Push(7)
 		expected.head.Push(12)
 		expected.head.Push(14)
@@ -171,8 +177,6 @@ func TestEnd(t *testing.T) {
 		expected.head.Push(5)
 		p := NewPointer()
 		ss := p.ss
-		ss.head.size = 4
-		ss.head.data = make([]int, 4)
 		ss.head.Push(7)
 		ss.head.Push(0)
 		ss.Begin(p)
@@ -211,9 +215,9 @@ func TestUnder(t *testing.T) {
 		expected.head.Push(0)
 		expected.head.Push(0)
 		expected.head.Push(6)
-		expected.head.next.Pop()
-		expected.head.next.Pop()
-		expected.head.next.Pop()
+		expected.head.Next().Pop()
+		expected.head.Next().Pop()
+		expected.head.Next().Pop()
 		p := NewPointer()
 		ss := p.ss
 		ss.head.Push(1)
@@ -231,9 +235,9 @@ func TestUnder(t *testing.T) {
 		pe := NewPointer()
 		expected := NewStackStack()
 		expected.Begin(pe)
-		expected.head.next.Push(12)
-		expected.head.next.Push(5)
-		expected.head.next.Push(8)
+		expected.head.Next().Push(12)
+		expected.head.Next().Push(5)
+		expected.head.Next().Push(8)
 		expected.head.Push(8)
 		expected.head.Push(5)
 		expected.head.Push(12)
diff --git a/pkg/pointer/stack.go b/pkg/pointer/stack.go
index ba51c7c..b08b354 100644
--- a/pkg/pointer/stack.go
+++ b/pkg/pointer/stack.go
@@ -1,54 +1,13 @@
 package pointer
 
-type Stack struct {
-	size   int
-	height int
-	data   []int
-	next   *Stack // Pointer to the next element in the stack stack
+func (ss *StackStack) Pop() int {
+	return ss.head.Pop()
 }
 
-func NewStack() *Stack {
-	return &Stack{
-		size:   32,
-		height: 0,
-		data:   make([]int, 32),
-		next:   nil,
-	}
+func (ss *StackStack) Push(v int) {
+	ss.head.Push(v)
 }
 
-func (s *Stack) Clear() {
-	s.height = 0
-}
-
-func (s *Stack) Duplicate() {
-	if s.height > 0 {
-		s.Push(s.data[s.height-1])
-	} else {
-		s.Push(0)
-		s.Push(0)
-	}
-}
-
-func (s *Stack) Pop() int {
-	if s.height > 0 {
-		s.height--
-		return s.data[s.height]
-	}
-	return 0
-}
-
-func (s *Stack) Push(value int) {
-	if s.height >= s.size {
-		s.size += 32
-		s.data = append(s.data, make([]int, 32)...)
-	}
-	s.data[s.height] = value
-	s.height++
-}
-
-func (s *Stack) Swap() {
-	a := s.Pop()
-	b := s.Pop()
-	s.Push(a)
-	s.Push(b)
+func (s *StackStack) YCommandPick(n int, h int) {
+	s.head.YCommandPick(n, h)
 }
diff --git a/pkg/stack/min.go b/pkg/stack/min.go
new file mode 100644
index 0000000..e97aaed
--- /dev/null
+++ b/pkg/stack/min.go
@@ -0,0 +1,8 @@
+package stack
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}
diff --git a/pkg/stack/stack.go b/pkg/stack/stack.go
new file mode 100644
index 0000000..c307133
--- /dev/null
+++ b/pkg/stack/stack.go
@@ -0,0 +1,105 @@
+package stack
+
+type Stack struct {
+	size   int
+	height int
+	data   []int
+	next   *Stack // Pointer to the next element in the stack stack
+}
+
+func NewStack(size int, next *Stack) *Stack {
+	return &Stack{
+		size:   size,
+		height: 0,
+		data:   make([]int, size),
+		next:   next,
+	}
+}
+
+func (s *Stack) Clear() {
+	s.height = 0
+}
+
+func (s *Stack) Duplicate() {
+	if s.height > 0 {
+		s.Push(s.data[s.height-1])
+	} else {
+		s.Push(0)
+		s.Push(0)
+	}
+}
+
+func (s *Stack) Pop() int {
+	if s.height > 0 {
+		s.height--
+		return s.data[s.height]
+	}
+	return 0
+}
+
+func (s *Stack) Push(value int) {
+	if s.height >= s.size {
+		s.size += 32
+		s.data = append(s.data, make([]int, 32)...)
+	}
+	s.data[s.height] = value
+	s.height++
+}
+
+func (s *Stack) Swap() {
+	a := s.Pop()
+	b := s.Pop()
+	s.Push(a)
+	s.Push(b)
+}
+
+func (s Stack) GetHeights() []int {
+	if s.next != nil {
+		return append(s.next.GetHeights(), s.height)
+	} else {
+		return []int{s.height}
+	}
+}
+
+func (toss *Stack) Transfert(soss *Stack, n int) {
+	// Implements a value transfert between two stacks, intended for use with the '{'
+	// (aka begin) and '}' (aka end) stackstack commands
+	toss.height += n
+	if toss.height > toss.size {
+		toss.data = append(toss.data, make([]int, toss.height-toss.size)...)
+		toss.size = toss.height
+	}
+	for i := 1; i <= min(soss.height, n); i++ {
+		toss.data[toss.height-i] = soss.data[soss.height-i]
+		for i := min(soss.height, n) + 1; i <= n; i++ {
+			toss.data[toss.height-i] = 0
+		}
+	}
+	soss.height -= n
+	if soss.height < 0 {
+		soss.height = 0
+	}
+}
+
+func (s Stack) Next() *Stack {
+	return s.next
+}
+
+func (s *Stack) Discard(n int) {
+	// Implements a discard mechanism intended for use with the '}'(aka end) stackstack command
+	s.height -= n
+	if s.height < 0 {
+		s.height = 0
+	}
+}
+
+func (s *Stack) YCommandPick(n int, h int) {
+	if n > s.height {
+		s.height = 1
+		s.data[0] = 0
+	} else {
+		v := s.data[s.height-n]
+		s.height = h
+		s.Push(v)
+	}
+}
diff --git a/pkg/pointer/stack_test.go b/pkg/stack/stack_test.go
index 35700fd..2f15d3a 100644
--- a/pkg/pointer/stack_test.go
+++ b/pkg/stack/stack_test.go
@@ -1,4 +1,4 @@
-package pointer
+package stack
 
 import (
 	"testing"
@@ -7,15 +7,15 @@ import (
 )
 
 func TestClear(t *testing.T) {
-	s := NewStack()
+	s := NewStack(32, nil)
 	s.Clear()
 	require.Equal(t, 0, s.height)
 }
 
 func TestDupicate(t *testing.T) {
-	expected := NewStack()
+	expected := NewStack(32, nil)
 	expected.height = 2
-	s := NewStack()
+	s := NewStack(32, nil)
 	s.Duplicate()
 	require.Equal(t, expected.height, s.height)
 	s.Push(12)
@@ -27,7 +27,7 @@ func TestDupicate(t *testing.T) {
 }
 
 func TestPop(t *testing.T) {
-	s := NewStack()
+	s := NewStack(32, nil)
 	v := s.Pop()
 	require.Equal(t, 0, v)
 	s.Push(12)
@@ -41,7 +41,7 @@ func TestPop(t *testing.T) {
 }
 
 func TestPush(t *testing.T) {
-	s := NewStack()
+	s := NewStack(32, nil)
 	for i := 0; i < 32; i++ {
 		s.Push(i)
 	}
@@ -51,8 +51,8 @@ func TestPush(t *testing.T) {
 }
 
 func TestSwap(t *testing.T) {
-	s := NewStack()
-	s2 := NewStack()
+	s := NewStack(32, nil)
+	s2 := NewStack(32, nil)
 	s.Swap()
 	s2.Push(0)
 	s2.Push(0)
@@ -73,3 +73,11 @@ func TestSwap(t *testing.T) {
 	s.Swap()
 	require.Equal(t, s2, s)
 }
+
+func TestHeights(t *testing.T) {
+	// TODO
+}
+
+func TestTransfert(t *testing.T) {
+	// TODO
+}