Add the view-map command and some exploration of results

internal/maps/maps.go

@@ -5,6 +5,7 @@ import (
 	"compress/gzip"
 	"encoding/binary"
 	"fmt"
+	"io"
 	"io/ioutil"
 	"log"
 	"os"
@@ -18,6 +19,17 @@ var (
 	notImplemented        = fmt.Errorf("Not implemented")
 )
 
+const (
+	MaxHeight = 7   // Z coordinate
+	MaxLength = 100 // Y coordinate
+	MaxWidth  = 130 // X coordinate
+
+	CellSize = 16 // seems to be
+
+	cellDataOffset = 0x100 // tentatively
+	cellDataSize   = MaxHeight * MaxLength * MaxWidth * CellSize
+)
+
 type Header struct {
 	IsCampaignMap uint32 // Tentatively: 0 = no, 1 = yes
 	MinWidth      uint32
@@ -31,7 +43,37 @@ type Header struct {
 	Magic         [8]byte // "\x08\x00WHMAP\x00"
 	Unknown5      uint32
 	Unknown6      uint32
-	SetName       [8]byte // Or is it a null-terminated string?
+	SetName       [8]byte // Links to a filename in `/Sets/*.set`
+	// Need to investigate the rest of the header too
+}
+
+func (h Header) Width() int {
+	return int(h.MaxWidth - h.MinWidth)
+}
+
+func (h Header) Length() int {
+	return int(h.MaxLength - h.MinLength)
+}
+
+func (h Header) Height() int {
+	return MaxHeight
+}
+
+type Cell []byte // FIXME: need to deconstruct this into the various fields
+
+// Cells is always a fixed size; use At to get a cell according to x,y,z
+type Cells []byte
+
+// FIXME: Ordering may be incorrect? I assume z,y,x for now...
+func (c Cells) At(x, y, z int) Cell {
+	start :=
+		(z * MaxLength * MaxWidth * CellSize) +
+			(y * MaxWidth * CellSize) +
+			(x * CellSize)
+
+	end := start + CellSize
+
+	return Cell(c[start:end:end])
 }
 
 func (h Header) Check() []error {
@@ -49,7 +91,7 @@ func (h Header) Check() []error {
 
 type GameMap struct {
 	Header
-
+	Cells
 	// TODO: parse this into sections
 	Text string
 }
@@ -57,8 +99,8 @@ type GameMap struct {
 // A game map contains a .txt and a .map. If they're in the same directory,
 // just pass the directory + basename to load both
 func LoadGameMap(prefix string) (*GameMap, error) {
-	for _, mapExt := range []string{".MAP", ".map"} {
-		for _, txtExt := range []string{".TXT", ".txt"} {
+	for _, txtExt := range []string{".TXT", ".txt"} {
+		for _, mapExt := range []string{".MAP", ".map"} {
 			out, err := LoadGameMapByFiles(prefix+mapExt, prefix+txtExt)
 			if err != nil && !os.IsNotExist(err) {
 				return nil, err
@@ -146,5 +188,16 @@ func loadMapFile(filename string) (*GameMap, error) {
 		return nil, fmt.Errorf("Error parsing %s: %v", filename, err)
 	}
 
+	// no gzip.SeekReader, so discard unread header bytes for now
+	discardSize := int64(cellDataOffset - binary.Size(&out.Header))
+	if _, err := io.CopyN(ioutil.Discard, zr, discardSize); err != nil {
+		return nil, err
+	}
+
+	out.Cells = make(Cells, cellDataSize)
+	if err := binary.Read(zr, binary.LittleEndian, &out.Cells); err != nil {
+		return nil, fmt.Errorf("Error parsing %s: %v", filename, err)
+	}
+
 	return &out, nil
 }