renamed assets so that they are more consistent

testing purposes (so that the reader has something to read)

go.mod

@@ -1,5 +1,14 @@
 module maze-solver
 
-go 1.20
+go 1.21
 
-require golang.org/x/exp v0.0.0-20230801115018-d63ba01acd4b
+require (
+	github.com/mazznoer/colorgrad v0.9.1
+	golang.org/x/exp v0.0.0-20230801115018-d63ba01acd4b
+)
+
+require (
+	github.com/lucasb-eyer/go-colorful v1.2.0 // indirect
+	github.com/mazznoer/csscolorparser v0.1.2 // indirect
+	golang.org/x/image v0.11.0
+)

go.sum

@@ -1,2 +1,41 @@
+github.com/lucasb-eyer/go-colorful v1.2.0 h1:1nnpGOrhyZZuNyfu1QjKiUICQ74+3FNCN69Aj6K7nkY=
+github.com/lucasb-eyer/go-colorful v1.2.0/go.mod h1:R4dSotOR9KMtayYi1e77YzuveK+i7ruzyGqttikkLy0=
+github.com/mazznoer/colorgrad v0.9.1 h1:MB80JYVndKWSMEM1beNqnuOowWGhoQc3DXWXkFp6JlM=
+github.com/mazznoer/colorgrad v0.9.1/go.mod h1:WX2R9wt9B47+txJZVVpM9LY+LAGIdi4lTI5wIyreDH4=
+github.com/mazznoer/csscolorparser v0.1.2 h1:/UBHuQg792ePmGFzTQAC9u+XbFr7/HzP/Gj70Phyz2A=
+github.com/mazznoer/csscolorparser v0.1.2/go.mod h1:Aj22+L/rYN/Y6bj3bYqO3N6g1dtdHtGfQ32xZ5PJQic=
+github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
 golang.org/x/exp v0.0.0-20230801115018-d63ba01acd4b h1:r+vk0EmXNmekl0S0BascoeeoHk/L7wmaW2QF90K+kYI=
 golang.org/x/exp v0.0.0-20230801115018-d63ba01acd4b/go.mod h1:FXUEEKJgO7OQYeo8N01OfiKP8RXMtf6e8aTskBGqWdc=
+golang.org/x/image v0.11.0 h1:ds2RoQvBvYTiJkwpSFDwCcDFNX7DqjL2WsUgTNk0Ooo=
+golang.org/x/image v0.11.0/go.mod h1:bglhjqbqVuEb9e9+eNR45Jfu7D+T4Qan+NhQk8Ck2P8=
+golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
+golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
+golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
+golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
+golang.org/x/net v0.6.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs=
+golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
+golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
+golang.org/x/term v0.5.0/go.mod h1:jMB1sMXY+tzblOD4FWmEbocvup2/aLOaQEp7JmGp78k=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
+golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
+golang.org/x/text v0.12.0/go.mod h1:TvPlkZtksWOMsz7fbANvkp4WM8x/WCo/om8BMLbz+aE=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
+golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
+golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU=
+golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

io/reader/image.go

@@ -1,9 +1,74 @@
 package reader
 
-import "maze-solver/maze"
+import (
+	"image"
+	"image/color"
+	"image/png"
+	"os"
 
-type ImageReader struct{}
+	"golang.org/x/image/draw"
+)
 
-func (r *ImageReader) Read(filename string) (*maze.Maze, error) {
-	return nil, nil
+type ImageReader struct {
+	Filename              string
+	PathColor, WallColor  color.Color
+	CellWidth, CellHeight int
+}
+
+func (r *ImageReader) Read() (*RawMaze, error) {
+	image, err := r.getShrunkImage()
+	if err != nil {
+		return nil, err
+	}
+
+	width, height := image.Bounds().Max.X, image.Bounds().Max.Y
+	ret := &RawMaze{
+		Width:  width,
+		Height: height,
+		Data:   make([][]byte, height),
+	}
+
+	n_chunks := width/CHUNK_SIZE + 1
+
+	for i := 0; i < height; i++ {
+		ret.Data[i] = make([]byte, n_chunks)
+	}
+
+	for y := 0; y < height; y++ {
+		for i := 0; i < n_chunks; i++ {
+			var chunk byte = 0 // all walls
+
+			end_index := min((i+1)*CHUNK_SIZE, width)
+
+			for x := i * CHUNK_SIZE; x < end_index; x++ {
+				c := image.At(x, y)
+				if c == r.PathColor {
+					chunk |= 1 << (CHUNK_SIZE - 1 - (x - i*CHUNK_SIZE))
+				}
+			}
+
+			ret.Data[y][i] = chunk
+		}
+	}
+
+	return ret, nil
+}
+
+func (r *ImageReader) getShrunkImage() (*image.RGBA, error) {
+	input, err := os.Open(r.Filename)
+	if err != nil {
+		return nil, err
+	}
+	defer input.Close()
+
+	// Decode the image (from PNG to image.Image):
+	src, _ := png.Decode(input)
+
+	// Set the expected size that you want:
+	dst := image.NewRGBA(image.Rect(0, 0, src.Bounds().Max.X/r.CellWidth, src.Bounds().Max.Y/r.CellHeight))
+
+	// Resize:
+	draw.NearestNeighbor.Scale(dst, dst.Rect, src, src.Bounds(), draw.Over, nil)
+
+	return dst, nil
 }

io/reader/image_test.go

@@ -0,0 +1,112 @@
+package reader
+
+import (
+	"image/color"
+	"maze-solver/utils"
+	"testing"
+)
+
+func TestImageReader(t *testing.T) {
+	white := color.RGBA{255, 255, 255, 255}
+	black := color.RGBA{0, 0, 0, 255}
+	tests := []struct {
+		name                  string
+		width, height         int
+		cellWidth, cellHeight int
+		pathColor, wallColor  color.Color
+		filename              string
+		expected              [][]byte
+	}{
+		{
+			"Trivial",
+			5, 3,
+			40, 40,
+			white, black,
+			"../../assets/trivial.png",
+			[][]byte{
+				{0b_00100_000},
+				{0b_01110_000},
+				{0b_00010_000},
+			},
+		},
+		{
+			"Trivial Bigger",
+			7, 5,
+			40, 40,
+			white, black,
+			"../../assets/trivial-bigger.png",
+			[][]byte{
+				{0b_0001000_0},
+				{0b_0001000_0},
+				{0b_0111110_0},
+				{0b_0000010_0},
+				{0b_0000010_0},
+			},
+		},
+		{
+			"Bigger Staggered",
+			7, 5,
+			40, 40,
+
+			white, black,
+			"../../assets/trivial-bigger-staggered.png",
+			[][]byte{
+				{0b_0001000_0},
+				{0b_0001000_0},
+				{0b_0111110_0},
+				{0b_0000100_0},
+				{0b_0000100_0},
+			},
+		},
+		{
+			"Normal",
+			11, 11,
+			40, 40,
+			white, black,
+			"../../assets/normal.png",
+			[][]byte{
+				{0b_00000100, 0b000_00000},
+				{0b_01111101, 0b110_00000},
+				{0b_00000100, 0b010_00000},
+				{0b_01110111, 0b110_00000},
+				{0b_01010000, 0b010_00000},
+				{0b_01011111, 0b110_00000},
+				{0b_00010001, 0b010_00000},
+				{0b_01110111, 0b010_00000},
+				{0b_01000000, 0b010_00000},
+				{0b_01111101, 0b110_00000},
+				{0b_00000100, 0b000_00000},
+			},
+		},
+	}
+
+	for _, test := range tests {
+		reader := ImageReader{
+			Filename:   test.filename,
+			PathColor:  test.pathColor,
+			WallColor:  test.wallColor,
+			CellWidth:  test.cellWidth,
+			CellHeight: test.cellHeight,
+		}
+		got, err := reader.Read()
+		if err != nil {
+			t.Fatalf("%s: got error while reading, got\n%v", test.filename, err)
+		}
+
+		utils.AssertEqual(t, got.Width, test.width, "%s: width of raw maze don't match", test.name)
+		utils.AssertEqual(t, got.Height, test.height, "%s: height of raw maze don't match", test.name)
+		utils.AssertEqual(t, len(got.Data), len(test.expected), "%s: don't have the same number of rows", test.name)
+
+		for y, line_exp := range test.expected {
+			line_got := got.Data[y]
+			utils.AssertEqual(t, len(line_got), len(line_exp), "%s (line %v): don't have same number of chunks", test.name, y)
+
+			for i, chunk_exp := range line_exp {
+				chunk_got := line_got[i]
+				if chunk_got != chunk_exp {
+					t.Fatalf("%s (line %v): chunk %v don't coincide, %08b, want %08b", test.name, y, i, chunk_got, chunk_exp)
+				}
+			}
+		}
+	}
+}

io/writer/image.go

@@ -1,11 +1,110 @@
 package writer
 
 import (
+	"errors"
+	"image"
+	"image/color"
+	"image/draw"
+	"image/png"
 	"maze-solver/maze"
+	"os"
+
+	"github.com/mazznoer/colorgrad"
 )
 
-type ImageWriter struct{}
+type ImageWriter struct {
+	Filename              string
+	Maze                  *maze.SolvedMaze
+	CellWidth, CellHeight int
+	WallColor, PathColor  color.Color
+	SolutionGradient      colorgrad.Gradient
+	img                   *image.RGBA
+}
 
-func (w *ImageWriter) Write(filename string, maze *maze.SolvedMaze) error {
+func (w *ImageWriter) Write() error {
+	if w.Filename[len(w.Filename)-4:] != ".png" {
+		return errors.New("Filename of ImageWriter doesn't have .png extension. The only suppported image type is png")
+	}
+
+	w.img = image.NewRGBA(image.Rect(0, 0, w.Maze.Width*w.CellWidth, w.Maze.Height*w.CellHeight))
+
+	// Fill the image with walls
+	draw.Draw(w.img, w.img.Bounds(), &image.Uniform{w.WallColor}, image.Pt(0, 0), draw.Src)
+
+	// Fill in the paths
+	var x0, y0, width, height int
+	for _, node := range w.Maze.Nodes {
+		x0 = node.Coords.X * w.CellWidth
+		y0 = node.Coords.Y * w.CellHeight
+		if node.Right != nil {
+			width = (node.Right.Coords.X - node.Coords.X + 1) * w.CellWidth
+			height = w.CellHeight
+			w.draw(x0, y0, width, height, w.PathColor)
+		}
+
+		if node.Down != nil {
+			width = w.CellWidth
+			height = (node.Down.Coords.Y - node.Coords.Y + 1) * w.CellHeight
+			w.draw(x0, y0, width, height, w.PathColor)
+		}
+	}
+
+	// Fill in the solution
+	total_len := w.getSolutionLength()
+	colors := w.SolutionGradient.Colors(uint(total_len + 1))
+	c := 0
+	width, height = w.CellWidth, w.CellHeight
+	for i, from := range w.Maze.Solution[:len(w.Maze.Solution)-1] {
+		to := w.Maze.Solution[i+1]
+		if from.Coords.X == to.Coords.X {
+			x0 = from.Coords.X * w.CellWidth
+
+			for y := from.Coords.Y; y < to.Coords.Y; y++ {
+				y0 = y * w.CellHeight
+				w.draw(x0, y0, width, height, colors[c])
+				c++
+			}
+			y0 = to.Coords.Y * w.CellHeight
+			w.draw(x0, y0, width, height, colors[c])
+		} else {
+			y0 = from.Coords.Y * w.CellHeight
+
+			if from.Coords.X < to.Coords.X {
+				for x := from.Coords.X; x < to.Coords.X; x++ {
+					x0 = x * w.CellWidth
+					w.draw(x0, y0, width, height, colors[c])
+					c++
+				}
+			} else {
+				for x := from.Coords.X; x > to.Coords.X; x-- {
+					x0 = x * w.CellWidth
+					w.draw(x0, y0, width, height, colors[c])
+					c++
+				}
+			}
+			x0 = to.Coords.X * w.CellWidth
+			w.draw(x0, y0, width, height, colors[c])
+		}
+	}
+
+	f, err := os.Create(w.Filename)
+	if err != nil {
+		return err
+	}
+	png.Encode(f, w.img)
+	f.Close()
 	return nil
 }
+
+func (w *ImageWriter) getSolutionLength() int {
+	ret := 0
+	for i, node := range w.Maze.Solution[:len(w.Maze.Solution)-1] {
+		next := w.Maze.Solution[i+1]
+		ret += int(node.Coords.Distance(next.Coords))
+	}
+	return ret
+}
+
+func (w *ImageWriter) draw(x0, y0, width, height int, color color.Color) {
+	draw.Draw(w.img, image.Rect(x0, y0, x0+width, y0+height), &image.Uniform{color}, image.Pt(0, 0), draw.Src)
+}

io/writer/strings.go

@@ -0,0 +1,72 @@
+package writer
+
+import (
+	"bytes"
+	"fmt"
+	"maze-solver/maze"
+)
+
+type StringsWriter struct {
+	PathChar, WallChar byte
+	SolutionChar       byte
+	Maze               *maze.SolvedMaze
+	lines              [][]byte
+}
+
+func (w *StringsWriter) Write() error {
+	w.lines = make([][]byte, w.Maze.Height)
+
+	// Fill the lines with walls
+	for y := 0; y < w.Maze.Height; y++ {
+		w.lines[y] = bytes.Repeat([]byte{w.WallChar}, w.Maze.Width)
+	}
+
+	// Fill in the paths
+	for _, node := range w.Maze.Nodes {
+		if node.Right != nil {
+			w.fillHorizontally(node.Coords, node.Right.Coords, w.PathChar)
+		}
+		if node.Down != nil {
+			w.fillVertically(node.Coords, node.Down.Coords, w.PathChar)
+		}
+	}
+
+	// Fill in the solution
+	for i := 0; i < len(w.Maze.Solution)-1; i++ {
+		current := w.Maze.Solution[i].Coords
+		next := w.Maze.Solution[i+1].Coords
+
+		if current.X == next.X {
+			w.fillVertically(current, next, w.SolutionChar)
+		} else {
+			w.fillHorizontally(current, next, w.SolutionChar)
+		}
+	}
+
+	return nil
+}
+
+func (w *StringsWriter) fillHorizontally(from maze.Coordinates, to maze.Coordinates, char byte) {
+	y := from.Y
+	if from.X > to.X {
+		from, to = to, from
+	}
+	for x := from.X; x <= to.X; x++ {
+		w.lines[y][x] = char
+	}
+}
+
+func (w *StringsWriter) fillVertically(from maze.Coordinates, to maze.Coordinates, char byte) {
+	x := from.X
+	for y := from.Y; y <= to.Y; y++ {
+		w.lines[y][x] = char
+	}
+}
+
+func (w *StringsWriter) GetLines() []string {
+	ret := make([]string, len(w.lines))
+	for i, line := range w.lines {
+		ret[i] = fmt.Sprint(string(line))
+	}
+	return ret
+}

io/writer/strings_test.go

@@ -0,0 +1,88 @@
+package writer
+
+import (
+	"fmt"
+	"maze-solver/maze"
+	"maze-solver/utils"
+	"testing"
+)
+
+func TestStringsWriter(t *testing.T) {
+	tests := []struct {
+		name                             string
+		m                                *maze.SolvedMaze
+		pathChar, wallChar, solutionChar byte
+		expected                         []string
+	}{
+		{
+			"Trivial",
+			trivial(),
+			' ', '#', '.',
+			[]string{
+				"##.##",
+				"# ..#",
+				"###.#",
+			},
+		},
+		{
+			"Bigger",
+			bigger(),
+			'_', '~', '*',
+			[]string{
+				"~~~*~~~",
+				"~~~*~~~",
+				"~__***~",
+				"~~~~~*~",
+				"~~~~~*~",
+			},
+		},
+		{
+			"Bigger Staggered",
+			bigger_staggered(),
+			' ', '#', '.',
+			[]string{
+				"###.###",
+				"###.###",
+				"#  .. #",
+				"####.##",
+				"####.##",
+			},
+		},
+		{
+			"Normal",
+			normal(),
+			' ', '#', '.',
+			[]string{
+				"#####.#####",
+				"#    .#   #",
+				"#####.### #",
+				"#   #.....#",
+				"# # #####.#",
+				"# #.......#",
+				"###.### # #",
+				"#...#   # #",
+				"#.####### #",
+				"#.....#   #",
+				"#####.#####",
+			},
+		},
+	}
+
+	for _, test := range tests {
+		fmt.Printf("----------- %s -----------\n", test.name)
+		writer := StringsWriter{
+			PathChar:     test.pathChar,
+			WallChar:     test.wallChar,
+			SolutionChar: test.solutionChar,
+			Maze:         test.m,
+		}
+		writer.Write()
+		got := writer.GetLines()
+
+		utils.AssertEqual(t, len(got), len(test.expected), "%s: different amount of lines.", test.name)
+
+		for i, line := range test.expected {
+			utils.AssertEqual(t, got[i], line, "%s, line %v: not what we expected.", test.name, i)
+		}
+	}
+}

io/writer/utils.go

@@ -0,0 +1,291 @@
+package writer
+
+import "maze-solver/maze"
+
+func trivial() *maze.SolvedMaze {
+	/* trivial.txt
+	   ## ##
+	   #   #
+	   ### #
+
+	   Nodes are
+	   ##0##
+	   #123#
+	   ###4#
+	*/
+	ret := &maze.SolvedMaze{}
+	nodes := make([]*maze.Node, 5)
+
+	nodes[0] = maze.NewNode(maze.Coordinates{X: 2, Y: 0})
+
+	nodes[1] = maze.NewNode(maze.Coordinates{X: 1, Y: 1})
+	nodes[2] = maze.NewNode(maze.Coordinates{X: 2, Y: 1})
+	nodes[3] = maze.NewNode(maze.Coordinates{X: 3, Y: 1})
+
+	nodes[4] = maze.NewNode(maze.Coordinates{X: 3, Y: 2})
+
+	nodes[0].Down = nodes[2]
+
+	nodes[1].Right = nodes[2]
+
+	nodes[2].Up = nodes[0]
+	nodes[2].Left = nodes[1]
+	nodes[2].Right = nodes[3]
+
+	nodes[3].Left = nodes[2]
+	nodes[3].Down = nodes[4]
+
+	nodes[4].Up = nodes[3]
+
+	solution := []*maze.Node{
+		nodes[0], nodes[2], nodes[3], nodes[4],
+	}
+
+	ret.Nodes = nodes
+	ret.Width = 5
+	ret.Height = 3
+
+	ret.Solution = solution
+
+	return ret
+}
+
+func bigger() *maze.SolvedMaze {
+	/* trivial-bigger.txt
+	   ### ###
+	   ### ###
+	   #     #
+	   ##### #
+	   ##### #
+
+	   Nodes are
+	   ###0###
+	   ### ###
+	   #1 2 3#
+	   ##### #
+	   #####4#
+	*/
+	nodes := make([]*maze.Node, 5)
+
+	nodes[0] = maze.NewNode(maze.Coordinates{X: 3, Y: 0})
+
+	nodes[1] = maze.NewNode(maze.Coordinates{X: 1, Y: 2})
+	nodes[2] = maze.NewNode(maze.Coordinates{X: 3, Y: 2})
+	nodes[3] = maze.NewNode(maze.Coordinates{X: 5, Y: 2})
+
+	nodes[4] = maze.NewNode(maze.Coordinates{X: 5, Y: 4})
+
+	nodes[0].Down = nodes[2]
+
+	nodes[1].Right = nodes[2]
+
+	nodes[2].Up = nodes[0]
+	nodes[2].Left = nodes[1]
+	nodes[2].Right = nodes[3]
+
+	nodes[3].Left = nodes[2]
+	nodes[3].Down = nodes[4]
+
+	nodes[4].Up = nodes[3]
+
+	ret := &maze.SolvedMaze{
+		Maze: maze.Maze{
+			Width:  7,
+			Height: 5,
+			Nodes:  nodes,
+		},
+		Solution: []*maze.Node{
+			nodes[0], nodes[2], nodes[3], nodes[4],
+		},
+	}
+
+	return ret
+}
+
+func bigger_staggered() *maze.SolvedMaze {
+	/* trivial-bigger-staggered.txt
+	   ### ###
+	   ### ###
+	   #     #
+	   #### ##
+	   #### ##
+
+	   Nodes are
+	   ###0###
+	   ### ###
+	   #1 243#
+	   #### ##
+	   ####5##
+	*/
+	nodes := make([]*maze.Node, 6)
+
+	nodes[0] = maze.NewNode(maze.Coordinates{X: 3, Y: 0})
+
+	nodes[1] = maze.NewNode(maze.Coordinates{X: 1, Y: 2})
+	nodes[2] = maze.NewNode(maze.Coordinates{X: 3, Y: 2})
+	nodes[3] = maze.NewNode(maze.Coordinates{X: 5, Y: 2})
+
+	nodes[4] = maze.NewNode(maze.Coordinates{X: 4, Y: 2})
+
+	nodes[5] = maze.NewNode(maze.Coordinates{X: 4, Y: 4})
+
+	nodes[0].Down = nodes[2]
+
+	nodes[1].Right = nodes[2]
+
+	nodes[2].Up = nodes[0]
+	nodes[2].Left = nodes[1]
+	nodes[2].Right = nodes[4]
+
+	nodes[3].Left = nodes[4]
+
+	nodes[4].Left = nodes[2]
+	nodes[4].Right = nodes[3]
+	nodes[4].Down = nodes[5]
+
+	nodes[5].Up = nodes[4]
+
+	ret := &maze.SolvedMaze{
+		Maze: maze.Maze{
+			Width:  7,
+			Height: 5,
+			Nodes:  nodes,
+		},
+		Solution: []*maze.Node{
+			nodes[0], nodes[2], nodes[4], nodes[5],
+		},
+	}
+
+	return ret
+}
+
+func normal() *maze.SolvedMaze {
+	/* normal.txt
+		##### #####
+		#     #   #
+		##### ### #
+		#   #     #
+		# # ##### #
+		# #       #
+		### ### # #
+		#   #   # #
+		# ####### #
+		#     #   #
+		##### #####
+
+	    Nodes are
+		#####0#####
+		#1   2#3 4#
+		##### ### #
+		#5 6#7   8#
+		# # ##### #
+		#9#A   F B#
+		### ### # #
+		#C D#E G# #
+		# ####### #
+		#H   I#J K#
+		#####L#####
+	*/
+	nodes := make([]*maze.Node, 22)
+
+	// ---- Node creation ----
+	coords := []struct{ x, y int }{
+		{5, 0}, // 0
+
+		{1, 1}, // 1
+		{5, 1}, // 2
+		{7, 1}, // 3
+		{9, 1}, // 4
+
+		{1, 3}, // 5
+		{3, 3}, // 6
+		{5, 3}, // 7
+		{9, 3}, // 8
+
+		{1, 5}, // 9
+		{3, 5}, // A (10)
+		{9, 5}, // B (11)
+
+		{1, 7}, // C (12)
+		{3, 7}, // D (13)
+		{5, 7}, // E (14)
+		{7, 5}, // F (15)
+		{7, 7}, // G (16)
+
+		{1, 9}, // H (17)
+		{5, 9}, // I (18)
+		{7, 9}, // J (19)
+		{9, 9}, // K (20)
+
+		{5, 10}, // L (21)
+	}
+
+	for i, coord := range coords {
+		nodes[i] = maze.NewNode(maze.Coordinates{X: coord.x, Y: coord.y})
+	}
+
+	// ---- Node linking ----
+	// Vertical
+	links := []struct {
+		from, to int
+	}{
+		{0, 2},
+		{2, 7},
+		{4, 8},
+		{5, 9},
+		{6, 10},
+		{8, 11},
+		{10, 13},
+		{15, 16},
+		{11, 20},
+		{12, 17},
+		{18, 21},
+	}
+	for _, link := range links {
+		nodes[link.from].Down = nodes[link.to]
+		nodes[link.to].Up = nodes[link.from]
+	}
+
+	links = []struct {
+		from, to int
+	}{
+		{1, 2},
+		{3, 4},
+		{5, 6},
+		{7, 8},
+		{10, 15},
+		{15, 11},
+		{12, 13},
+		{14, 16},
+		{17, 18},
+		{19, 20},
+	}
+	for _, link := range links {
+		nodes[link.from].Right = nodes[link.to]
+		nodes[link.to].Left = nodes[link.from]
+	}
+
+	ret := &maze.SolvedMaze{
+		Maze: maze.Maze{
+			Width:  11,
+			Height: 11,
+			Nodes:  nodes,
+		},
+		Solution: []*maze.Node{
+			nodes[0],
+			nodes[2],
+			nodes[7],
+			nodes[8],
+			nodes[11],
+			nodes[15],
+			nodes[10],
+			nodes[13],
+			nodes[12],
+			nodes[17],
+			nodes[18],
+			nodes[21],
+		},
+	}
+
+	return ret
+}

io/writer/writer.go

@@ -1,7 +1,5 @@
 package writer
 
-import "maze-solver/maze"
-
 type Writer interface {
-	Write(filename string, maze *maze.SolvedMaze) error
+	Write() error
 }

maze/maze.go

@@ -1,8 +1,31 @@
 package maze
 
+import "math"
+
 type Coordinates struct {
 	X, Y int
 }
+
+func (c Coordinates) Distance(o Coordinates) float64 {
+	x, y := float64(o.X-c.X), float64(o.Y-c.Y)
+
+	if y == 0 {
+		if x < 0 {
+			return -x
+		}
+		return x
+	}
+
+	if x == 0 {
+		if y < 0 {
+			return -y
+		}
+		return y
+	}
+
+	return math.Sqrt(x*x + y*y)
+}
+
 type Node struct {
 	Coords      Coordinates
 	Up, Down    *Node

maze/parser/parser_test.go

@@ -205,7 +205,7 @@ func TestTextReadTrivialBiggerStaggered(t *testing.T) {
 }
 
 func TestTextReadNormal(t *testing.T) {
-	/* trivial-bigger-staggered.txt
+	/* normal.txt
 		##### #####
 		#     #   #
 		##### ### #
@@ -231,7 +231,6 @@ func TestTextReadNormal(t *testing.T) {
 		#H   I#J K#
 		#####L#####
 	*/
-	// TODO: we are not detecting vertical dead-ends that go downwards
 	nodes := make([]*maze.Node, 22)
 
 	// ---- Node creation ----
@@ -271,68 +270,45 @@ func TestTextReadNormal(t *testing.T) {
 	}
 
 	// ---- Node linking ----
-	nodes[0].Down = nodes[2]
+	// Vertical
+	links := []struct {
+		from, to int
+	}{
+		{0, 2},
+		{2, 7},
+		{4, 8},
+		{5, 9},
+		{6, 10},
+		{8, 11},
+		{10, 13},
+		{15, 16},
+		{11, 20},
+		{12, 17},
+		{18, 21},
+	}
+	for _, link := range links {
+		nodes[link.from].Down = nodes[link.to]
+		nodes[link.to].Up = nodes[link.from]
+	}
 
-	nodes[1].Right = nodes[2]
-
-	nodes[2].Up = nodes[0]
-	nodes[2].Left = nodes[1]
-	nodes[2].Down = nodes[7]
-
-	nodes[3].Right = nodes[4]
-
-	nodes[4].Left = nodes[3]
-	nodes[4].Down = nodes[8]
-
-	nodes[5].Right = nodes[6]
-	nodes[5].Down = nodes[9]
-
-	nodes[6].Left = nodes[5]
-	nodes[6].Down = nodes[10]
-
-	nodes[7].Right = nodes[8]
-
-	nodes[8].Up = nodes[4]
-	nodes[8].Left = nodes[7]
-	nodes[8].Down = nodes[11]
-
-	nodes[9].Up = nodes[5]
-
-	nodes[10].Up = nodes[6]
-	nodes[10].Right = nodes[15]
-	nodes[10].Down = nodes[13]
-
-	nodes[11].Up = nodes[8]
-	nodes[11].Left = nodes[15]
-	nodes[11].Down = nodes[20]
-
-	nodes[12].Right = nodes[13]
-	nodes[12].Down = nodes[17]
-
-	nodes[13].Up = nodes[10]
-	nodes[13].Left = nodes[12]
-
-	nodes[14].Right = nodes[16]
-
-	nodes[15].Left = nodes[10]
-	nodes[15].Right = nodes[11]
-	nodes[15].Down = nodes[16]
-
-	nodes[16].Up = nodes[15]
-	nodes[16].Left = nodes[14]
-
-	nodes[17].Up = nodes[12]
-	nodes[17].Right = nodes[18]
-
-	nodes[18].Left = nodes[17]
-	nodes[18].Down = nodes[21]
-
-	nodes[19].Right = nodes[20]
-
-	nodes[20].Up = nodes[11]
-	nodes[20].Left = nodes[19]
-
-	nodes[21].Up = nodes[18]
+	links = []struct {
+		from, to int
+	}{
+		{1, 2},
+		{3, 4},
+		{5, 6},
+		{7, 8},
+		{10, 15},
+		{15, 11},
+		{12, 13},
+		{14, 16},
+		{17, 18},
+		{19, 20},
+	}
+	for _, link := range links {
+		nodes[link.from].Right = nodes[link.to]
+		nodes[link.to].Left = nodes[link.from]
+	}
 
 	reader := reader.TextReader{
 		Filename: "../../assets/normal.txt",