feat: target board generation [PROPOSAL]

boardgen/boardgen.go

@@ -0,0 +1,304 @@
+package boardgen
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"slices"
+	"strings"
+	"text/template"
+
+	"github.com/tinygo-org/tinygo/goenv"
+)
+
+type Board struct {
+	Name       string            `json:"name,omitempty"`
+	BoardFiles map[string]string `json:"files,omitempty"`
+	Imports    []string          `json:"imports,omitempty"`
+	InitFuncs  []string          `json:"init-funcs,omitempty"`
+	PinAliases []PinAlias        `json:"pin-aliases,omitempty"`
+	Constants  []Variable        `json:"constants,omitempty"`
+	Variables  []Variable        `json:"variables,omitempty"`
+	fileDirs   []string          `json:"-"`
+	tempDirs   []string          `json:"-"`
+}
+
+func (board *Board) Files() map[string]string {
+	if board == nil || board.BoardFiles == nil {
+		return nil
+	}
+	return board.BoardFiles
+}
+
+func (board *Board) DirsFromFiles() []string {
+	if board == nil || board.BoardFiles == nil {
+		return []string{}
+	}
+
+	for dst, src := range board.BoardFiles {
+		dir := filepath.Clean(dst)
+		if !isDir(src) {
+			dir = filepath.Dir(dir)
+		}
+		if !slices.Contains(board.fileDirs, dir) {
+			board.fileDirs = append(board.fileDirs, dir+"/")
+		}
+	}
+	return board.fileDirs
+}
+
+func (board *Board) TempDirs() []string {
+	if board == nil || board.tempDirs == nil {
+		return []string{}
+	}
+	return board.tempDirs
+}
+
+type PinAlias struct {
+	Name string `json:"name,omitempty"`
+	Type string `json:"type,omitempty"`
+	Pin  string `json:"pin,omitempty"`
+}
+
+func (pa PinAlias) NameLen() int {
+	return len(pa.Name)
+}
+
+func (pa PinAlias) TypeLen() int {
+	return len(pa.Type)
+}
+
+func (pa PinAlias) Print(nameLen int, typeLen int) string {
+	if typeLen != 0 {
+		// Add an extra space between the name and type
+		nameLen++
+	}
+	pattern := "\t%-*s%-*s = %s"
+	return fmt.Sprintf(pattern, nameLen, pa.Name, typeLen, pa.Type, pa.Pin)
+}
+
+type Variable struct {
+	Name  string `json:"name,omitempty"`
+	Type  string `json:"type,omitempty"`
+	Quote bool   `json:"quote,omitempty"`
+	Value string `json:"value,omitempty"`
+}
+
+func (v Variable) NameLen() int {
+	return len(v.Name)
+}
+
+func (v Variable) TypeLen() int {
+	return len(v.Type)
+}
+
+func (v Variable) Print(nameLen int, typeLen int) string {
+	if typeLen != 0 {
+		// Add an extra space between the name and type
+		nameLen++
+	}
+	pattern := "\t%-*s%-*s = %s"
+	if v.Quote {
+		pattern = "\t%-*s%-*s = %q"
+	}
+	return fmt.Sprintf(pattern, nameLen, v.Name, typeLen, v.Type, v.Value)
+}
+
+type boardData struct {
+	BuildTags []string `json:"build-tags,omitempty"`
+	Board     *Board   `json:"board,omitempty"`
+}
+
+const boardTemplate = `// Code generated by board-generator. DO NOT EDIT.
+{{ buildtags .BuildTags -}}
+
+package machine
+
+{{ imports .Board.Imports -}}
+
+// Pin aliases for the {{.Board.Name}}.
+{{ pinAliases .Board.PinAliases -}}
+
+{{ constants .Board.Constants -}}
+
+{{ variables .Board.Variables -}}
+
+{{ initFuncs .Board.InitFuncs -}}
+`
+
+var funcMap = template.FuncMap{
+	"buildtags": func(tags []string) string {
+		if len(tags) == 0 {
+			return "\n"
+		}
+		return "//go:build " + strings.Join(tags, " && ") + "\n\n"
+	},
+	"constants": func(constants []Variable) string {
+		if len(constants) == 0 {
+			return ""
+		}
+
+		longName, longType := longestVar[Variable](constants)
+		var builder strings.Builder
+
+		builder.WriteString("\nconst (\n")
+		for _, v := range constants {
+			if v.Name == "" || v.Value == "" {
+				// Can't declare a constant with no value
+				builder.WriteString(fmt.Sprintf("// Invalid constant: %+v\n", v))
+				continue
+			}
+			builder.WriteString(v.Print(longName, longType))
+			builder.WriteString("\n")
+		}
+		builder.WriteString(")\n")
+		return builder.String()
+	},
+	"imports": func(imports []string) string {
+		if len(imports) == 0 {
+			return ""
+		}
+		var builder strings.Builder
+		builder.WriteString("\nimport (\n")
+		for _, imp := range imports {
+			builder.WriteString(fmt.Sprintf("\t\"%s\"\n", imp))
+		}
+		builder.WriteString(")\n")
+		return builder.String()
+	},
+	"initFuncs": func(funcs []string) string {
+		if len(funcs) == 0 {
+			return ""
+		}
+		var builder strings.Builder
+		builder.WriteString("\nfunc init() {\n")
+		for _, fn := range funcs {
+			builder.WriteString(fmt.Sprintf("\t%s\n", fn))
+		}
+		builder.WriteString("}\n")
+		return builder.String()
+	},
+	"pinAliases": func(pinAliases []PinAlias) string {
+		if len(pinAliases) == 0 {
+			return ""
+		}
+
+		longName, longType := longestVar[PinAlias](pinAliases)
+		var builder strings.Builder
+
+		builder.WriteString("\nconst (\n")
+		for _, pa := range pinAliases {
+			if pa.Name == "" || pa.Pin == "" {
+				// Can't declare a pin alias with no pin or name
+				builder.WriteString(fmt.Sprintf("// Invalid pin alias: %+v\n", pa))
+				continue
+			}
+			builder.WriteString(pa.Print(longName, longType))
+			builder.WriteString("\n")
+		}
+		builder.WriteString(")\n")
+		return builder.String()
+	},
+	"variables": func(variables []Variable) string {
+		if len(variables) == 0 {
+			return ""
+		}
+
+		longName, longType := longestVar[Variable](variables)
+		var builder strings.Builder
+
+		builder.WriteString("\nvar (\n")
+
+		for _, v := range variables {
+			if v.Name == "" || v.Type == "" && v.Value == "" {
+				// Can't declare a variable with no name or no type/value
+				builder.WriteString(fmt.Sprintf("// Invalid variable: %+v\n", v))
+				continue
+			}
+			builder.WriteString(v.Print(longName, longType))
+			builder.WriteString("\n")
+		}
+		builder.WriteString(")\n")
+		return builder.String()
+	},
+}
+
+type varStruct interface {
+	NameLen() int
+	TypeLen() int
+}
+
+func longestVar[T varStruct](v []T) (int, int) {
+	longName := 0
+	longType := 0
+	for _, variable := range v {
+		if variable.NameLen() > longName {
+			longName = variable.NameLen()
+		}
+		if variable.TypeLen() > longType {
+			longType = variable.TypeLen()
+		}
+	}
+	return longName, longType
+}
+
+func (board *Board) Generate(target string, buildTags []string) error {
+	if board == nil {
+		return fmt.Errorf("board is nil")
+	}
+
+	board.BoardFiles = make(map[string]string)
+
+	// Make a temp directory to import the target's generated files for later import
+	err := os.MkdirAll(goenv.Get("GOCACHE"), 0777)
+	if err != nil {
+		return err
+	}
+	tmpDir, err := os.MkdirTemp(goenv.Get("GOCACHE"), target+".tmp")
+	if err != nil {
+		return err
+	}
+	board.tempDirs = append(board.tempDirs, tmpDir)
+
+	fileName := "boardgen_" + target + ".go"
+	destPath := filepath.Join("machine", fileName)
+	sourcePath := filepath.Join(tmpDir, fileName)
+
+	// Generate a go file for the board
+	boardData := boardData{
+		BuildTags: buildTags,
+		Board:     board,
+	}
+	tmpl, err := template.New("board").Funcs(funcMap).Parse(boardTemplate)
+	if err != nil {
+		return err
+	}
+
+	fp, err := os.Create(sourcePath)
+	if err != nil {
+		return err
+	}
+	defer fp.Close()
+
+	err = tmpl.Execute(fp, boardData)
+	if err != nil {
+		return err
+	}
+	// Write the file to disk ASAP
+	err = fp.Sync()
+	if err != nil {
+		return err
+	}
+
+	board.BoardFiles[destPath] = sourcePath
+
+	return nil
+}
+
+func isDir(path string) bool {
+	f, err := os.Stat(path)
+	if err != nil {
+		return false
+	}
+	return f.IsDir()
+}