adding initial support to generate content type from more descriptive cli args

1 files changed, 192 insertions, 0 deletions

diff --git a/cmd/ponzu/generate.go b/cmd/ponzu/generate.go
new file mode 100644
index 0000000..9325d1d
--- /dev/null
+++ b/cmd/ponzu/generate.go
@@ -0,0 +1,192 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"go/format"
+	"html/template"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+type generateType struct {
+	Name    string
+	Initial string
+	Fields  []generateField
+}
+
+type generateField struct {
+	Name     string
+	TypeName string
+	JSONName string
+}
+
+// blog title:string Author:string PostCategory:string content:string some_thing:int
+func parseType(args []string) (generateType, error) {
+	t := generateType{
+		Name: fieldName(args[0]),
+	}
+	t.Initial = strings.ToLower(string(t.Name[0]))
+
+	fields := args[1:]
+	for _, field := range fields {
+		f, err := parseField(field)
+		if err != nil {
+			return generateType{}, err
+		}
+
+		t.Fields = append(t.Fields, f)
+	}
+
+	return t, nil
+}
+
+func parseField(raw string) (generateField, error) {
+	// title:string
+	if !strings.Contains(raw, ":") {
+		return generateField{}, fmt.Errorf("Invalid generate argument. [%s]", raw)
+	}
+
+	pair := strings.Split(raw, ":")
+	field := generateField{
+		Name:     fieldName(pair[0]),
+		TypeName: strings.ToLower(pair[1]),
+		JSONName: fieldJSONName(pair[0]),
+	}
+
+	return field, nil
+}
+
+// get the initial field name passed and check it for all possible cases
+// MyTitle:string myTitle:string my_title:string -> MyTitle
+// error-message:string -> ErrorMessage
+func fieldName(name string) string {
+	// remove _ or - if first character
+	if name[0] == '-' || name[0] == '_' {
+		name = name[1:]
+	}
+
+	// remove _ or - if last character
+	if name[len(name)-1] == '-' || name[len(name)-1] == '_' {
+		name = name[:len(name)-1]
+	}
+
+	// upcase the first character
+	name = strings.ToUpper(string(name[0])) + name[1:]
+
+	// remove _ or - character, and upcase the character immediately following
+	for i := 0; i < len(name); i++ {
+		r := rune(name[i])
+		if isUnderscore(r) || isHyphen(r) {
+			up := strings.ToUpper(string(name[i+1]))
+			name = name[:i] + up + name[i+2:]
+		}
+	}
+
+	return name
+}
+
+// get the initial field name passed and convert to json-like name
+// MyTitle:string myTitle:string my_title:string -> my_title
+// error-message:string -> error-message
+func fieldJSONName(name string) string {
+	// remove _ or - if first character
+	if name[0] == '-' || name[0] == '_' {
+		name = name[1:]
+	}
+
+	// downcase the first character
+	name = strings.ToLower(string(name[0])) + name[1:]
+
+	// check for uppercase character, downcase and insert _ before it if i-1
+	// isn't already _ or -
+	for i := 0; i < len(name); i++ {
+		r := rune(name[i])
+		if isUpper(r) {
+			low := strings.ToLower(string(r))
+			if name[i-1] == '_' || name[i-1] == '-' {
+				name = name[:i] + low + name[i+1:]
+			} else {
+				name = name[:i] + "_" + low + name[i+1:]
+			}
+		}
+	}
+
+	return name
+}
+
+func isUpper(char rune) bool {
+	if char >= 'A' && char <= 'Z' {
+		return true
+	}
+
+	return false
+}
+
+func isUnderscore(char rune) bool {
+	return char == '_'
+}
+
+func isHyphen(char rune) bool {
+	return char == '-'
+}
+
+func generateContentType(args []string, path string) error {
+	name := args[0]
+	fileName := strings.ToLower(name) + ".go"
+
+	// open file in ./content/ dir
+	// if exists, alert user of conflict
+	pwd, err := os.Getwd()
+	if err != nil {
+		return err
+	}
+
+	if path != "" {
+		pwd = path
+	}
+
+	contentDir := filepath.Join(pwd, "content")
+	filePath := filepath.Join(contentDir, fileName)
+
+	if _, err := os.Stat(filePath); !os.IsNotExist(err) {
+		return fmt.Errorf("Please remove '%s' before executing this command.", fileName)
+	}
+
+	// no file exists.. ok to write new one
+	file, err := os.Create(filePath)
+	defer file.Close()
+	if err != nil {
+		return err
+	}
+
+	// parse type info from args
+	gt, err := parseType(args)
+	if err != nil {
+		return fmt.Errorf("Failed to parse type args: %s", err.Error())
+	}
+
+	tmpl, err := template.ParseFiles("contentType.tmpl")
+	if err != nil {
+		return fmt.Errorf("Failed to parse template: %s", err.Error())
+	}
+
+	buf := &bytes.Buffer{}
+	err = tmpl.Execute(buf, gt)
+	if err != nil {
+		return fmt.Errorf("Failed to execute template: %s", err.Error())
+	}
+
+	fmtBuf, err := format.Source(buf.Bytes())
+	if err != nil {
+		return fmt.Errorf("Failed to format template: %s", err.Error())
+	}
+
+	_, err = file.Write(fmtBuf)
+	if err != nil {
+		return fmt.Errorf("Failed to write generated file buffer: %s", err.Error())
+	}
+
+	return nil
+}