Add CLI options

1 files changed, 50 insertions, 21 deletions

diff --git a/cli/cmd/compile.go b/cli/cmd/compile.go
index 6ad64b6..f2d56fa 100644
--- a/cli/cmd/compile.go
+++ b/cli/cmd/compile.go
@@ -3,7 +3,6 @@ package cmd
 import (
 	"encoding/json"
 	"fmt"
-	"io"
 	"io/ioutil"
 	"os"
 	"time"
@@ -13,6 +12,12 @@ import (
 	"github.com/spf13/cobra"
 )
 
+var compileFlags = struct {
+	debug   *bool
+	lexSpec *string
+	output  *string
+}{}
+
 func init() {
 	cmd := &cobra.Command{
 		Use:     "compile",
@@ -21,41 +26,47 @@ func init() {
 		Example: `  cat lexspec.json | maleeni compile > clexspec.json`,
 		RunE:    runCompile,
 	}
+	compileFlags.debug = cmd.Flags().BoolP("debug", "d", false, "enable logging")
+	compileFlags.lexSpec = cmd.Flags().StringP("lex-spec", "l", "", "lexical specification file path (default: stdin)")
+	compileFlags.output = cmd.Flags().StringP("output", "o", "", "output file path (default: stdout)")
 	rootCmd.AddCommand(cmd)
 }
 
 func runCompile(cmd *cobra.Command, args []string) (retErr error) {
-	lspec, err := readLexSpec()
+	lspec, err := readLexSpec(*compileFlags.lexSpec)
 	if err != nil {
 		return fmt.Errorf("Cannot read a lexical specification: %w", err)
 	}
-	var w io.Writer
-	{
+
+	var opts []compiler.CompilerOption
+	if *compileFlags.debug {
 		fileName := "maleeni-compile.log"
 		f, err := os.OpenFile(fileName, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0644)
 		if err != nil {
 			return fmt.Errorf("Cannot open the log file %s: %w", fileName, err)
 		}
 		defer f.Close()
-		w = f
-	}
-	fmt.Fprintf(w, `maleeni compile starts.
+		fmt.Fprintf(f, `maleeni compile starts.
 Date time: %v
 ---
 `, time.Now().Format(time.RFC3339))
-	defer func() {
-		fmt.Fprintf(w, "---\n")
-		if retErr != nil {
-			fmt.Fprintf(w, "maleeni compile failed: %v\n", retErr)
-		} else {
-			fmt.Fprintf(w, "maleeni compile succeeded.\n")
-		}
-	}()
-	clspec, err := compiler.Compile(lspec, compiler.EnableLogging(w))
+		defer func() {
+			fmt.Fprintf(f, "---\n")
+			if retErr != nil {
+				fmt.Fprintf(f, "maleeni compile failed: %v\n", retErr)
+			} else {
+				fmt.Fprintf(f, "maleeni compile succeeded.\n")
+			}
+		}()
+
+		opts = append(opts, compiler.EnableLogging(f))
+	}
+
+	clspec, err := compiler.Compile(lspec, opts...)
 	if err != nil {
 		return err
 	}
-	err = writeCompiledLexSpec(clspec)
+	err = writeCompiledLexSpec(clspec, *compileFlags.output)
 	if err != nil {
 		return fmt.Errorf("Cannot write a compiled lexical specification: %w", err)
 	}
@@ -63,8 +74,17 @@ Date time: %v
 	return nil
 }
 
-func readLexSpec() (*spec.LexSpec, error) {
-	data, err := ioutil.ReadAll(os.Stdin)
+func readLexSpec(path string) (*spec.LexSpec, error) {
+	r := os.Stdin
+	if path != "" {
+		f, err := os.Open(path)
+		if err != nil {
+			return nil, fmt.Errorf("Cannot open the lexical specification file %s: %w", path, err)
+		}
+		defer f.Close()
+		r = f
+	}
+	data, err := ioutil.ReadAll(r)
 	if err != nil {
 		return nil, err
 	}
@@ -76,11 +96,20 @@ func readLexSpec() (*spec.LexSpec, error) {
 	return lspec, nil
 }
 
-func writeCompiledLexSpec(clspec *spec.CompiledLexSpec) error {
+func writeCompiledLexSpec(clspec *spec.CompiledLexSpec, path string) error {
 	out, err := json.Marshal(clspec)
 	if err != nil {
 		return err
 	}
-	fmt.Fprintf(os.Stdout, "%v\n", string(out))
+	w := os.Stdout
+	if path != "" {
+		f, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0644)
+		if err != nil {
+			return fmt.Errorf("Cannot open the output file %s: %w", path, err)
+		}
+		defer f.Close()
+		w = f
+	}
+	fmt.Fprintf(w, "%v\n", string(out))
 	return nil
 }