1 files changed, 115 insertions, 0 deletions
diff --git a/cmd/maleeni/compile.go b/cmd/maleeni/compile.go
new file mode 100644
index 0000000..6a5e303
--- /dev/null
+++ b/cmd/maleeni/compile.go
@@ -0,0 +1,115 @@
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"time"
+
+	"github.com/nihei9/maleeni/compiler"
+	"github.com/nihei9/maleeni/spec"
+	"github.com/spf13/cobra"
+)
+
+var compileFlags = struct {
+	debug   *bool
+	lexSpec *string
+	output  *string
+}{}
+
+func init() {
+	cmd := &cobra.Command{
+		Use:     "compile",
+		Short:   "Compile a lexical specification into a DFA",
+		Long:    `compile takes a lexical specification and generates a DFA accepting the tokens described in the specification.`,
+		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(*compileFlags.lexSpec)
+	if err != nil {
+		return fmt.Errorf("Cannot read a lexical specification: %w", err)
+	}
+
+	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()
+		fmt.Fprintf(f, `maleeni compile starts.
+Date time: %v
+---
+`, time.Now().Format(time.RFC3339))
+		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, *compileFlags.output)
+	if err != nil {
+		return fmt.Errorf("Cannot write a compiled lexical specification: %w", err)
+	}
+
+	return nil
+}
+
+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
+	}
+	lspec := &spec.LexSpec{}
+	err = json.Unmarshal(data, lspec)
+	if err != nil {
+		return nil, err
+	}
+	return lspec, nil
+}
+
+func writeCompiledLexSpec(clspec *spec.CompiledLexSpec, path string) error {
+	out, err := json.Marshal(clspec)
+	if err != nil {
+		return err
+	}
+	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
+}