Simple JSON parsing. Will need extension for tables.

1 files changed, 66 insertions, 4 deletions

diff --git a/src/JSONReader.java b/src/JSONReader.java
index 8d670b6..45f6bd5 100644
--- a/src/JSONReader.java
+++ b/src/JSONReader.java
@@ -1,4 +1,5 @@
 import java.util.HashMap;
+import java.util.ArrayList;
 import java.io.*;
 
 /*
@@ -6,6 +7,8 @@ import java.io.*;
  * Kian Agheli
  * 
  * References:
+ * https://googlefonts.github.io/gf-guide/metadata.html
+ * https://stackoverflow.com/questions/3880274/how-to-convert-the-object-to-string-in-java
  * 
  * Date:
  * 2024-05-08
@@ -15,23 +18,75 @@ import java.io.*;
  */
 
 public class JSONReader extends Reader {
+	/* metadata.pb is not exactly JSON, but so close to it
+	that it's practically a subset of JSON with fewer quotation
+	marks. If set, this is a pb file. */
+	private boolean pb;
+
 	public JSONReader(File file) {
 		super(file);
+		pb = false;
+	}
+	
+	private String composeKey(String key) {
+		if (!pb) {
+			key = "\"" + key + "\"";
+		}
+		key += ": ";
+		
+		return key;
 	}
 	
 	/**
 	 * Search for and return the first
 	 * match.
 	 */
-	public String get(String field) {
-		return null;
+	public String get(String key) {
+		key = composeKey(key);
+		
+		int start = this.getContents().indexOf(key);
+		if (start == -1) {
+			/* No match. */
+			return null;
+		}
+		
+		start += key.length();
+		/* This JSON is pretty-printed. */
+		int nl = this.getContents().indexOf("\n", start);
+		
+		/* Extract substring. Remove any quotation marks and commas. */
+		String substring = this.getContents().substring(start, nl);
+		return substring.replaceAll("[\",]", "");
 	}
 
 	/**
 	 * Search for and return all matches.
 	 */
-	public String[] getAll(String field) {
-		return null;
+	public String[] getAll(String key) {
+		key = composeKey(key);
+		
+		ArrayList<String> list = new ArrayList<String>();
+		int lastMatch = 0;
+		while ((lastMatch = this.getContents().indexOf(key, lastMatch)) != -1) {
+			lastMatch += key.length();
+			int start = lastMatch;
+			/* This JSON is pretty-printed. */
+			int nl = this.getContents().indexOf("\n", start);
+			if (nl == -1) {
+				/* EOF. */
+				nl = this.getContents().length();
+			}
+			
+			/* Extract substring. Remove any quotation marks and commas. */
+			String substring = this.getContents().substring(start, nl);
+			list.add(substring.replaceAll("[\",]", ""));
+		}
+		
+		/* The caller doesn't need the capabilites of an ArrayList, only
+		those of an array. */
+		String[] array = new String[list.size()];
+		list.toArray(array);
+		return array;
 	}
 	
 	/**
@@ -40,4 +95,11 @@ public class JSONReader extends Reader {
 	public String getTable(HashMap<String,String> name) {
 		return null;
 	}
+	
+	/**
+	 * Specify that this is the special PB format.
+	 * See https://googlefonts.github.io/gf-guide/metadata.html. */
+	public void setPb() {
+		this.pb = true;
+	}
 }