allow plugins to list / read runtime files

also renamed most of the new functions to be
more specific about what kind of files this is for.

cmd/micro/rtfiles.go

@@ -0,0 +1,144 @@
+package main
+
+import (
+	"io/ioutil"
+	"path"
+	"path/filepath"
+)
+
+const (
+	FILE_ColorScheme = "colorscheme"
+	FILE_Syntax      = "syntax"
+	FILE_Help        = "help"
+)
+
+// RuntimeFile allows the program to read runtime data like colorschemes or syntax files
+type RuntimeFile interface {
+	// Name returns a name of the file without paths or extensions
+	Name() string
+	// Data returns the content of the file.
+	Data() ([]byte, error)
+}
+
+// allFiles contains all available files, mapped by filetype
+var allFiles map[string][]RuntimeFile
+
+// some file on filesystem
+type realFile string
+
+// some asset file
+type assetFile string
+
+// some file on filesystem but with a different name
+type namedFile struct {
+	realFile
+	name string
+}
+
+func (rf realFile) Name() string {
+	fn := filepath.Base(string(rf))
+	return fn[:len(fn)-len(filepath.Ext(fn))]
+}
+
+func (rf realFile) Data() ([]byte, error) {
+	return ioutil.ReadFile(string(rf))
+}
+
+func (af assetFile) Name() string {
+	fn := path.Base(string(af))
+	return fn[:len(fn)-len(path.Ext(fn))]
+}
+
+func (af assetFile) Data() ([]byte, error) {
+	return Asset(string(af))
+}
+
+func (nf namedFile) Name() string {
+	return nf.name
+}
+
+// AddRuntimeFile registers a file for the given filetype
+func AddRuntimeFile(fileType string, file RuntimeFile) {
+	if allFiles == nil {
+		allFiles = make(map[string][]RuntimeFile)
+	}
+	allFiles[fileType] = append(allFiles[fileType], file)
+}
+
+// AddRuntimeFilesFromDirectory registers each file from the given directory for
+// the filetype which matches the file-pattern
+func AddRuntimeFilesFromDirectory(fileType, directory, pattern string) {
+	files, _ := ioutil.ReadDir(directory)
+	for _, f := range files {
+		if ok, _ := filepath.Match(pattern, f.Name()); !f.IsDir() && ok {
+			fullPath := filepath.Join(directory, f.Name())
+			AddRuntimeFile(fileType, realFile(fullPath))
+		}
+	}
+}
+
+// AddRuntimeFilesFromDirectory registers each file from the given asset-directory for
+// the filetype which matches the file-pattern
+func AddRuntimeFilesFromAssets(fileType, directory, pattern string) {
+	files, err := AssetDir(directory)
+	if err != nil {
+		return
+	}
+	for _, f := range files {
+		if ok, _ := path.Match(pattern, f); ok {
+			AddRuntimeFile(fileType, assetFile(path.Join(directory, f)))
+		}
+	}
+}
+
+// FindRuntimeFile finds a runtime file of the given filetype and name
+// will return nil if no file was found
+func FindRuntimeFile(fileType, name string) RuntimeFile {
+	for _, f := range ListRuntimeFiles(fileType) {
+		if f.Name() == name {
+			return f
+		}
+	}
+	return nil
+}
+
+// Lists all known runtime files for the given filetype
+func ListRuntimeFiles(fileType string) []RuntimeFile {
+	if files, ok := allFiles[fileType]; ok {
+		return files
+	} else {
+		return []RuntimeFile{}
+	}
+}
+
+// Initializes all assets file and the config directory
+func InitRuntimeFiles() {
+	add := func(fileType, dir, pattern string) {
+		AddRuntimeFilesFromDirectory(fileType, filepath.Join(configDir, dir), pattern)
+		AddRuntimeFilesFromAssets(fileType, path.Join("runtime", dir), pattern)
+	}
+
+	add(FILE_ColorScheme, "colorschemes", "*.micro")
+	add(FILE_Syntax, "syntax", "*.micro")
+	add(FILE_Help, "help", "*.md")
+}
+
+// Allows plugin scripts to read the content of a runtime file
+func PluginReadRuntimeFile(fileType, name string) string {
+	if file := FindRuntimeFile(fileType, name); file != nil {
+		if data, err := file.Data(); err == nil {
+			return string(data)
+		}
+	}
+	return ""
+}
+
+// Allows plugins to lists all runtime files of the given type
+func PluginListRuntimeFiles(fileType string) []string {
+	files := ListRuntimeFiles(fileType)
+	result := make([]string, len(files))
+	for i, f := range files {
+		result[i] = f.Name()
+	}
+	return result
+}