Add scripting

.github/workflows/build.yml

@@ -16,7 +16,7 @@ jobs:
     runs-on: ubuntu-20.04
     strategy:
       matrix:
-        go: [ 1.18 ]
+        go: [ "1.20" ]
     env:
       DISPLAY: ':99.0'
     steps:
@@ -25,12 +25,12 @@ jobs:
           sudo apt-get update
           sudo apt-get install libasound2-dev libgl1-mesa-dev libxcursor-dev libxi-dev libxinerama-dev libxrandr-dev libxxf86vm-dev
 
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v3
         with:
           fetch-depth: 0
 
       - name: Set up Go
-        uses: actions/setup-go@v2
+        uses: actions/setup-go@v4
         with:
           go-version: ${{ matrix.go }}
 

.vscode/launch.json

@@ -0,0 +1,16 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "Launch Package",
+            "type": "go",
+            "request": "launch",
+            "mode": "auto",
+            "program": "${fileDirname}",
+            "console": "externalTerminal"
+        }
+    ]
+}

README.md

@@ -39,7 +39,7 @@ Pi is under development. Only limited functionality is provided. API is not stab
 ## How to get started?
 
 1. Install dependencies 
-   * [Go 1.18+](https://go.dev/dl/)
+   * [Go 1.20+](https://go.dev/dl/)
    * If not on Windows, please install additional dependencies for [Linux](docs/install-linux.md) or [macOS](docs/install-macos.md).
 2. Try examples from [examples](examples) directory.
 3. Create a new game using provided [Github template](https://github.com/elgopher/pi-template).

devtools/control.go

@@ -4,6 +4,8 @@
 package devtools
 
 import (
+	"fmt"
+
 	"github.com/elgopher/pi"
 	"github.com/elgopher/pi/devtools/internal/snapshot"
 )
@@ -13,7 +15,15 @@ var (
 	timeWhenPaused float64
 )
 
+var helpShown bool
+
 func pauseGame() {
+	fmt.Println("Game paused")
+	if !helpShown {
+		helpShown = true
+		fmt.Println("\nPress right mouse button in the game window to show the toolbar.")
+		fmt.Println("Press P in the game window to take screenshot.")
+	}
 	gamePaused = true
 	timeWhenPaused = pi.TimeSeconds
 	snapshot.Take()
@@ -23,4 +33,5 @@ func resumeGame() {
 	gamePaused = false
 	pi.TimeSeconds = timeWhenPaused
 	snapshot.Draw()
+	fmt.Println("Game resumed")
 }

devtools/devtools.go

@@ -8,6 +8,7 @@ import (
 
 	"github.com/elgopher/pi"
 	"github.com/elgopher/pi/devtools/internal/inspector"
+	"github.com/elgopher/pi/devtools/internal/terminal"
 )
 
 var (
@@ -33,7 +34,8 @@ func MustRun(runBackend func() error) {
 	}
 
 	inspector.BgColor, inspector.FgColor = BgColor, FgColor
-	fmt.Println("Press F12 to pause the game and show devtools.")
+	fmt.Println("Press F12 in the game window to pause the game and activate devtools with terminal.")
+	fmt.Println("Terminal activated. Type help for help.")
 
 	pi.Update = func() {
 		updateDevTools()
@@ -53,6 +55,9 @@ func MustRun(runBackend func() error) {
 		}
 	}
 
+	terminal.StartReadingCommands()
+	defer terminal.StopReadingCommandsFromStdin()
+
 	if err := runBackend(); err != nil {
 		panic(fmt.Sprintf("Something terrible happened! Pi cannot be run: %v\n", err))
 	}

devtools/internal/inspector/measure.go

@@ -94,7 +94,7 @@ func (m *Measure) Update() {
 	case pi.MouseBtnp(pi.MouseLeft) && !distance.measuring:
 		distance.measuring = true
 		distance.startX, distance.startY = x, y
-		fmt.Printf("Measuring started at (%d, %d)\n", x, y)
+		fmt.Printf("\nMeasuring started at (%d, %d)\n", x, y)
 	case !pi.MouseBtn(pi.MouseLeft) && distance.measuring:
 		distance.measuring = false
 		dist, width, height := calcDistance()

devtools/internal/inspector/update.go

@@ -4,7 +4,6 @@
 package inspector
 
 import (
-	"fmt"
 	"math"
 
 	"github.com/elgopher/pi"
@@ -33,14 +32,7 @@ func calcDistance() (dist float64, width, height int) {
 	return
 }
 
-var helpShown bool
-
 func Update() {
-	if !helpShown {
-		helpShown = true
-		fmt.Println("Press right mouse button to show toolbar.")
-		fmt.Println("Press P to take screenshot.")
-	}
 
 	if !toolbar.visible {
 		tool.Update()

devtools/internal/interpreter/help.go

@@ -0,0 +1,114 @@
+package interpreter
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"os"
+	"os/exec"
+	"sort"
+	"strings"
+
+	"github.com/elgopher/pi/devtools/internal/interpreter/internal/lib"
+)
+
+func printHelp(topic string) {
+	switch topic {
+	case "":
+		println("This is interactive terminal. " +
+			"You can write Go code here, which will run immediately in the paused game. " +
+			"You can use all Pi packages: pi, key, state, snap, font, image and " +
+			"selection of standard packages: " + strings.Join(stdPackages(), ", ") + ". " +
+			"\n\n" +
+			"Type help topic for more information. For example: help pi or help pi.Spr")
+	default:
+		goDoc(topic)
+	}
+}
+
+func stdPackages() []string {
+	var packages []string
+	for _, p := range lib.AllPackages() {
+		if p.IsStdPackage() {
+			packages = append(packages, p.Alias)
+		}
+	}
+	sort.Strings(packages)
+	return packages
+}
+
+func goDoc(symbol string) {
+	fmt.Println("###############################################################################")
+
+	symbol = completeSymbol(symbol)
+	if symbolNotSupported(symbol) {
+		fmt.Println("no help found")
+		return
+	}
+
+	var args []string
+	args = append(args, "doc")
+	if shouldShowDetailedDescriptionForSymbol(symbol) {
+		args = append(args, "-all")
+	}
+	args = append(args, symbol)
+	command := exec.Command("go", args...)
+	command.Stdout = bufio.NewWriter(os.Stdout)
+	if err := command.Run(); err != nil {
+		var exitErr *exec.ExitError
+		if isExitErr := errors.As(err, &exitErr); isExitErr && exitErr.ExitCode() == 1 {
+			fmt.Println("no help found")
+			return
+		}
+		fmt.Println("problem getting help:", err)
+	}
+	return
+}
+
+func completeSymbol(symbol string) string {
+	packages := lib.AllPackages()
+
+	for _, p := range packages {
+		if p.Alias == symbol {
+			return p.Name
+		}
+	}
+
+	for _, p := range packages {
+		prefix := p.Alias + "."
+		if strings.HasPrefix(symbol, prefix) {
+			return p.Name + "." + symbol[len(prefix):]
+		}
+	}
+
+	return symbol
+}
+
+func symbolNotSupported(symbol string) bool {
+	packages := lib.AllPackages()
+
+	for _, p := range packages {
+		prefix := p.Name + "."
+		if strings.HasPrefix(symbol, prefix) || symbol == p.Name {
+			return false
+		}
+	}
+
+	return true
+}
+
+var symbolsWithDetailedDescription = []string{
+	"github.com/elgopher/pi.Button",
+	"github.com/elgopher/pi.MouseButton",
+	"github.com/elgopher/pi/key.Button",
+}
+
+func shouldShowDetailedDescriptionForSymbol(symbol string) bool {
+	for _, s := range symbolsWithDetailedDescription {
+		if symbol == s {
+			return true
+		}
+	}
+
+	return false
+}