Add Pi CLI

First supported command is "convert". It converts files from one format into another.

With this feature you can convert pico-8 file into Pi formats: sprite-sheet.png and audio.sfx

cmd/pi/README.md

@@ -0,0 +1,13 @@
+# pi command line interface
+
+## Install
+
+```sh 
+go install github.com/elgopher/pi/cmd/pi
+```
+
+## Run
+
+```shell
+pi [global options] command [command options] [arguments...]
+```

cmd/pi/cli.go

@@ -0,0 +1,57 @@
+// (c) 2022-2023 Jacek Olszak
+// This code is licensed under MIT license (see LICENSE for details)
+
+package main
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/urfave/cli/v2"
+
+	"github.com/elgopher/pi/cmd/pi/internal/convert"
+)
+
+func main() {
+	app := cli.App{
+		Usage: "Pi Command Line Interface",
+		Commands: []*cli.Command{
+			convertCmd(),
+		},
+	}
+	err := app.Run(os.Args)
+	if err != nil {
+		_, _ = os.Stderr.WriteString(err.Error())
+	}
+}
+
+func convertCmd() *cli.Command {
+	return &cli.Command{
+		Name:        "convert",
+		Usage:       "Converts one file format into another one",
+		Description: "Format of input and output file is deducted based on files extension.",
+		Flags: []cli.Flag{
+			&cli.StringFlag{
+				Name:    "format",
+				Aliases: []string{"f"},
+				Usage:   "Format of input file. Overrides what CLI deducted based on input file extension. For now, the only supported input format is p8.",
+			},
+		},
+		ArgsUsage: "input.file output.file",
+		Action: func(context *cli.Context) error {
+			inputFile := context.Args().Get(0)
+			outputFile := context.Args().Get(1)
+
+			if context.Args().Len() > 2 {
+				return fmt.Errorf("too many arguments")
+			}
+
+			command := convert.Command{
+				InputFormat: convert.InputFormat(context.String("format")),
+				InputFile:   inputFile,
+				OutputFile:  outputFile,
+			}
+			return command.Run()
+		},
+	}
+}

cmd/pi/go.mod

@@ -0,0 +1,14 @@
+module github.com/elgopher/pi/cmd/pi
+
+go 1.20
+
+require (
+	github.com/icza/bitio v1.1.0
+	github.com/urfave/cli/v2 v2.25.7
+)
+
+require (
+	github.com/cpuguy83/go-md2man/v2 v2.0.2 // indirect
+	github.com/russross/blackfriday/v2 v2.1.0 // indirect
+	github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 // indirect
+)

cmd/pi/go.sum

@@ -0,0 +1,12 @@
+github.com/cpuguy83/go-md2man/v2 v2.0.2 h1:p1EgwI/C7NhT0JmVkwCD2ZBK8j4aeHQX2pMHHBfMQ6w=
+github.com/cpuguy83/go-md2man/v2 v2.0.2/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
+github.com/icza/bitio v1.1.0 h1:ysX4vtldjdi3Ygai5m1cWy4oLkhWTAi+SyO6HC8L9T0=
+github.com/icza/bitio v1.1.0/go.mod h1:0jGnlLAx8MKMr9VGnn/4YrvZiprkvBelsVIbA9Jjr9A=
+github.com/icza/mighty v0.0.0-20180919140131-cfd07d671de6 h1:8UsGZ2rr2ksmEru6lToqnXgA8Mz1DP11X4zSJ159C3k=
+github.com/icza/mighty v0.0.0-20180919140131-cfd07d671de6/go.mod h1:xQig96I1VNBDIWGCdTt54nHt6EeI639SmHycLYL7FkA=
+github.com/russross/blackfriday/v2 v2.1.0 h1:JIOH55/0cWyOuilr9/qlrm0BSXldqnqwMsf35Ld67mk=
+github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
+github.com/urfave/cli/v2 v2.25.7 h1:VAzn5oq403l5pHjc4OhD54+XGO9cdKVL/7lDjF+iKUs=
+github.com/urfave/cli/v2 v2.25.7/go.mod h1:8qnjx1vcq5s2/wpsqoZFndg2CE5tNFyrTvS6SinrnYQ=
+github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 h1:bAn7/zixMGCfxrRTfdpNzjtPYqr8smhKouy9mxVdGPU=
+github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673/go.mod h1:N3UwUGtsrSj3ccvlPHLoLsHnpR27oXr4ZE984MbSER8=

cmd/pi/internal/convert/convert.go

@@ -0,0 +1,63 @@
+// (c) 2022-2023 Jacek Olszak
+// This code is licensed under MIT license (see LICENSE for details)
+
+package convert
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/elgopher/pi/cmd/pi/internal/convert/internal/p8"
+)
+
+type InputFormat string
+
+const (
+	InputFormatP8 = "p8"
+)
+
+type Command struct {
+	InputFormat
+	InputFile  string
+	OutputFile string
+}
+
+func (o Command) Run() error {
+	if o.InputFile == "" {
+		return fmt.Errorf("input file not provided")
+	}
+
+	if o.InputFormat != "" && o.InputFormat != InputFormatP8 {
+		return fmt.Errorf("input format %s not supported", o.InputFormat)
+	}
+
+	if o.InputFormat == "" {
+		if strings.HasSuffix(o.InputFile, ".p8") {
+			o.InputFormat = InputFormatP8
+		} else {
+			return fmt.Errorf("cannot deduct the format of %s input file", o.InputFile)
+		}
+	}
+
+	if o.OutputFile == "" {
+		return fmt.Errorf("output file not provided")
+	}
+
+	fmt.Printf("Converting %s to %s... ", o.InputFile, o.OutputFile)
+	fmt.Printf("Using %s input format... ", o.InputFormat)
+	if err := o.convert(); err != nil {
+		return err
+	}
+	fmt.Println("Done")
+	return nil
+}
+
+func (o Command) convert() error {
+	if o.InputFormat == InputFormatP8 {
+		if err := p8.ConvertToAudioSfx(o.InputFile, o.OutputFile); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

cmd/pi/internal/convert/internal/p8/p8.go

@@ -0,0 +1,134 @@
+package p8
+
+import (
+	"bytes"
+	"encoding/hex"
+	"fmt"
+	"os"
+
+	"github.com/icza/bitio"
+
+	"github.com/elgopher/pi/audio"
+)
+
+func ConvertToAudioSfx(inputFile, outputFile string) error {
+	parser := Parser{}
+	file, err := parser.Parse(inputFile)
+	if err != nil {
+		return fmt.Errorf("error parsing p8 file %s: %w", inputFile, err)
+	}
+
+	for _, section := range file.Sections {
+		if section.Name == "__sfx__" {
+			sfx, err := decodeSfx(section.Lines)
+			if err != nil {
+				return fmt.Errorf("error decoding __sfx__ section from p8 file %s: %w", inputFile, err)
+			}
+			audio.Sfx = sfx
+		}
+	}
+
+	bytes, err := audio.Save()
+	if err != nil {
+		return fmt.Errorf("saving audio failed: %w", err)
+	}
+
+	err = os.WriteFile(outputFile, bytes, 0644)
+	if err != nil {
+		return fmt.Errorf("writing %s failed: %w", outputFile, err)
+	}
+
+	return nil
+}
+
+func decodeSfx(lines []string) (sfx [64]audio.SoundEffect, err error) {
+	// each line is a sound effect
+	for no, line := range lines {
+		decoded, err := hex.DecodeString(line)
+		if err != nil {
+			return sfx, err
+		}
+
+		notes, err := decodeSfxNotes(decoded[4:])
+		if err != nil {
+			return sfx, err
+		}
+
+		editorModeAndFilters := bitio.NewReader(bytes.NewReader(decoded[0:1]))
+		editorMode, err := editorModeAndFilters.ReadBool()
+		if err != nil {
+			return sfx, err
+		}
+		_ = editorMode
+
+		noiz, err := editorModeAndFilters.ReadBool()
+		if err != nil {
+			return sfx, err
+		}
+
+		buzz, err := editorModeAndFilters.ReadBool()
+		if err != nil {
+			return sfx, err
+		}
+
+		detune, err := editorModeAndFilters.ReadBits(2)
+		if err != nil {
+			return sfx, err
+		}
+
+		reverb, err := editorModeAndFilters.ReadBits(2)
+		if err != nil {
+			return sfx, err
+		}
+
+		dampen, err := editorModeAndFilters.ReadBits(2)
+		if err != nil {
+			return sfx, err
+		}
+
+		sfx[no] = audio.SoundEffect{
+			Speed:     decoded[1],
+			LoopStart: decoded[2],
+			LoopStop:  decoded[3],
+			Notes:     notes,
+			Noiz:      noiz,
+			Buzz:      buzz,
+			Detune:    byte(detune),
+			Reverb:    byte(reverb),
+			Dampen:    byte(dampen),
+		}
+	}
+
+	return
+}
+
+func decodeSfxNotes(b []byte) (notes [32]audio.Note, err error) {
+	reader := bitio.NewReader(bytes.NewBuffer(b))
+	for i := 0; i < 32; i++ {
+		pitch, err := reader.ReadByte()
+		if err != nil {
+			return notes, err
+		}
+		notes[i].Pitch = audio.Pitch(pitch)
+
+		waveform, err := reader.ReadBits(4)
+		if err != nil {
+			return notes, err
+		}
+		notes[i].Instrument = audio.Instrument(waveform)
+
+		volume, err := reader.ReadBits(4)
+		if err != nil {
+			return notes, err
+		}
+		notes[i].Volume = audio.Volume(volume)
+
+		effect, err := reader.ReadBits(4)
+		if err != nil {
+			return notes, err
+		}
+		notes[i].Effect = audio.Effect(effect)
+	}
+
+	return
+}