1 files changed, 191 insertions, 0 deletions
diff --git a/internal/game/map.go b/internal/game/map.go
new file mode 100644
index 0000000..cd1012b
--- /dev/null
+++ b/internal/game/map.go
@@ -0,0 +1,191 @@
+package game
+
+import (
+	"thirdcollapse/internal/world"
+)
+
+type mapGraph struct {
+	posToRoom map[[2]int]int
+	roomToPos map[int][2]int
+}
+
+var bfsDirs = []struct {
+	dir    world.ExitDir
+	dx, dy int
+}{
+	{world.North, 0, -1},
+	{world.South, 0, 1},
+	{world.East, 1, 0},
+	{world.West, -1, 0},
+}
+
+func buildGraph(g *Game, startRoomID int) *mapGraph {
+	mg := &mapGraph{
+		posToRoom: make(map[[2]int]int),
+		roomToPos: make(map[int][2]int),
+	}
+
+	type node struct {
+		roomID int
+		x, y   int
+	}
+	queue := []node{{startRoomID, 0, 0}}
+	mg.posToRoom[[2]int{0, 0}] = startRoomID
+	mg.roomToPos[startRoomID] = [2]int{0, 0}
+
+	for len(queue) > 0 {
+		n := queue[0]
+		queue = queue[1:]
+
+		room, ok := loadRoom(g, n.roomID)
+		if !ok {
+			continue
+		}
+
+		for _, d := range bfsDirs {
+			targetID, ok := exitTarget(room, d.dir)
+			if !ok {
+				continue
+			}
+			if _, visited := mg.roomToPos[targetID]; visited {
+				continue
+			}
+			nx, ny := n.x + d.dx, n.y + d.dy
+			mg.posToRoom[[2]int{nx, ny}] = targetID
+			mg.roomToPos[targetID] = [2]int{nx, ny}
+			queue = append(queue, node{targetID, nx, ny})
+		}
+	}
+
+	return mg
+}
+
+func buildTinyMap(g *Game, roomID int) []string {
+	mg := buildGraph(g, roomID)
+
+	grid := make([][]rune, 5)
+	for i := range grid {
+		grid[i] = make([]rune, 5)
+		for j := range grid[i] {
+			grid[i][j] = ' '
+		}
+	}
+
+	for y := -1; y <= 1; y++ {
+		for x := -1; x <= 1; x++ {
+			pos := [2]int{x, y}
+			rid, ok := mg.posToRoom[pos]
+			if !ok {
+				continue
+			}
+			gr := (y + 1) * 2
+			gc := (x + 1) * 2
+			if rid == roomID {
+				grid[gr][gc] = '@'
+			} else {
+				grid[gr][gc] = roomMapSymbol(g, rid)
+			}
+		}
+	}
+
+	for y := -1; y <= 1; y++ {
+		for x := -1; x <= 0; x++ {
+			leftPos := [2]int{x, y}
+			rightPos := [2]int{x + 1, y}
+			leftRoom, leftOK := mg.posToRoom[leftPos]
+			rightRoom, rightOK := mg.posToRoom[rightPos]
+			if !leftOK || !rightOK {
+				continue
+			}
+			if exitsConnect(g, leftRoom, rightRoom, world.East, world.West) {
+				grid[(y+1)*2][(x+1)*2+1] = '─'
+			}
+		}
+	}
+
+	for y := -1; y <= 0; y++ {
+		for x := -1; x <= 1; x++ {
+			topPos := [2]int{x, y}
+			bottomPos := [2]int{x, y + 1}
+			topRoom, topOK := mg.posToRoom[topPos]
+			bottomRoom, bottomOK := mg.posToRoom[bottomPos]
+			if !topOK || !bottomOK {
+				continue
+			}
+			if exitsConnect(g, topRoom, bottomRoom, world.South, world.North) {
+				grid[(y+1)*2+1][(x+1)*2] = '│'
+			}
+		}
+	}
+
+	cur, _ := loadRoom(g, roomID)
+	if cur != nil {
+		if _, ok := exitTarget(cur, world.Up); ok {
+			grid[1][3] = '↑'
+		}
+		if _, ok := exitTarget(cur, world.Down); ok {
+			grid[3][1] = '↓'
+		}
+	}
+
+	lines := make([]string, 7)
+	lines[0] = "╔═════╗"
+	for row := 0; row < 5; row++ {
+		lines[row+1] = "║" + string(grid[row]) + "║"
+	}
+	lines[6] = "╚═════╝"
+
+	return lines
+}
+
+func exitsConnect(g *Game, room1, room2 int, dir12, dir21 world.ExitDir) bool {
+	r1, ok := loadRoom(g, room1)
+	if !ok {
+		return false
+	}
+	if id, ok := exitTarget(r1, dir12); ok && id == room2 {
+		return true
+	}
+	r2, ok := loadRoom(g, room2)
+	if !ok {
+		return false
+	}
+	if id, ok := exitTarget(r2, dir21); ok && id == room1 {
+		return true
+	}
+	return false
+}
+
+func exitTarget(room *world.Room, dir world.ExitDir) (int, bool) {
+	if room == nil {
+		return 0, false
+	}
+	exit, ok := room.Exits[dir]
+	if !ok {
+		return 0, false
+	}
+	return exit.Room, true
+}
+
+func loadRoom(g *Game, roomID int) (*world.Room, bool) {
+	if roomID == 0 {
+		return nil, false
+	}
+	room, err := g.World.LoadRoom(roomID)
+	if err != nil {
+		return nil, false
+	}
+	return room, true
+}
+
+func roomMapSymbol(g *Game, roomID int) rune {
+	room, ok := loadRoom(g, roomID)
+	if !ok {
+		return '?'
+	}
+	if room.MapSymbol != "" {
+		runes := []rune(room.MapSymbol)
+		return runes[0]
+	}
+	return 'o'
+}