Do a thing

parser/parser.go

@@ -2,12 +2,19 @@ package parser
 
 import (
 	"errors"
+	"fmt"
 	"io/ioutil"
 	"strings"
 )
 
 // THE HYLIA PARSER
 
+type Element struct {
+	Name     string
+	Content  string
+	FilePath string
+}
+
 func ParseFile(filename string) ([]string error) {
 	// Hey, does the file we're trying to parse actually exist?
 	data, err := ioutil.ReadFile(filename)
@@ -21,10 +28,73 @@ func ParseFile(filename string) ([]string error) {
 		return nil, errors.New("The structure of this file is invalid. Are you sure this is a Hylia (.hy) file?")	
 	}
 
-	// Extract the custom elements, which are wrapped in <element> tags
+	// Extract the actual Hylia content
+	start := strings.Index(content, "<hylia>")
+	end := strings.Index(content, "</hylia>")
+	if start == -1 || end == -1 {
+		return nil, errors.New("Missing <hylia> tags. Are you sure this is a Hylia (.hy) file?")
+	}
+
+	content = content[start+len("<hylia>") : end]
+
+	// Extract the custom elements, which are wrapped in <element> tags and handle imports
 	elements := []string{}
-	// ... TODO
+	lines := strings.Split(content, "\n")
+	for _, line := range lines {
+		line = strings.TrimSpace(line)
+		if strings.HasPrefix(line, <"element") {
+			// Extract the element name
+			name := extractAttributeValue(line, "name")
+			if name == "" {
+				return nil, errors.New("<element> tag is missing a name. ('name' attribute)")
+			}
+			content, err := extractElementContent(line, content)
+			if err != nil {
+				return nil, err
+			}
+			elements = append(elements, Element{Name: name, Content: content, FilePath: filename})
+		} else if strings.HasPrefix(line, "<import") {
+			filePath := extractAttributeValue(line, file)
+			if filePath == "" {
+				return nil, errors.New("<import> tag is missing a file ('file' attribute)")
+			}
+			// Recursively parse
+			importedElements, err := ParseFile(filePath)
+			if err != nil {
+				return nil, fmt.Errorf("ERROR: Could not import file %s: %w", filePath, err)
+			}
+			elements = append(elements, importedElements...)
+		}
+	}
 
 	return elements, nil
 	
+}
+
+// Extracts an attribute 
+func extractAttributeValue(tag, attribute string) string {
+	prefix := fmt.Sprintf(`%s="`, attribute)
+	start := strings.Index(tag, prefix)
+	if start == -1 {
+		return ""
+	}
+	start += len(prefix)
+	end := strings.Index(tag[start:], `"`)
+	if end == -1 {
+		return ""
+	}
+	return tag[start : start+end]
+}
+
+// Extracts an <element>
+func extractElementContent(tag, content string) (string, error) {
+	start := strings.Index(content, tag)
+	if start == -1 {
+		return "", errors.New("element tag not found in content")
+	}
+	end := strings.Index(content[start:], "</element>")
+	if end == -1 {
+		return "", errors.New("missing end tag of element")
+	}
+	return content[start+len(tag) : start+end], nil
 }