add doc comments to the build script

d/build/source/app.d

@@ -1,3 +1,6 @@
+/++
+This module is responsible for generating the data file from the info.json files.
++/
 module app;
 
 import std.file : readText, write, exists, remove;
@@ -6,11 +9,19 @@ import asdf;
 import std.stdio : writeln, File;
 import std.algorithm;
 import std.array;
-import std.regex;
 
-const string dataPath = "../../_data/";
-const string dataFile = "../source/kuliya/data.d";
+/++
+Data path to the info.json files
++/
+const string DATA_PATH = "../../_data/";
+/++
+Data D file to save the schema
++/
+const string DATA_FILE = "../source/kuliya/data.d";
 
+/++
+Kuliya types
++/
 enum Type
 {
     UNIVERSITY,
@@ -23,35 +34,58 @@ enum Type
     SECTOR
 }
 
+/++
+Kuliya name
++/
 struct Name
 {
+    /// Arabic name
     string ar;
+    /// English name
     string en;
+    /// French name
     string fr;
 }
 
+/++
+Kuliya terms
++/
 struct Terms
 {
+    /// Number of slots per year
     int perYear;
+    /// Slots
     int[] slots;
 }
 
+/++
+Kuliya schema
++/
 struct Schema
 {
+    /// Name
     Name name;
+    /// Type
     Type type;
+    /// Terms
     @serdeOptional
     Nullable!Terms terms;
 }
 
+/++
+Save schema to file
+Params:
+    schema = Schema to save
+    path = Path of the info.json file
++/
 void saveToFile(const Schema schema, string path)
 {
     // remove ../_data/ prefix and /info.json suffix from path
     const auto pathParts = path.splitter('/').array;
     const auto filePath = pathParts[3 .. $ - 1].join("/");
     // replace / with _ in filePath
     const auto filePathUnderscored = filePath.replace("/", "_");
-    File file = File(dataFile, "a");
+    File file = File(DATA_FILE, "a");
     file.writeln("immutable Schema ", filePathUnderscored, " = ");
     file.writeln("{");
     file.writeln("    Name(\"", schema.name.ar, "\", \"", schema.name.en, "\", \"", schema.name.fr, "\"),");
@@ -76,6 +110,13 @@ void saveToFile(const Schema schema, string path)
     file.close();
 }
 
+/++
+Parse info.json file to Schema struct
+Params:
+    path = Path of the info.json file
+Returns:
+    Schema
++/
 Schema parseInfoJson(string path)
 {
     const auto data = readText(path);
@@ -84,6 +125,11 @@ Schema parseInfoJson(string path)
     return schema;
 }
 
+/++
+Walk through directories and parse info.json files
+Params:
+    path = Path of the directory
++/
 void walkDirs(string path)
 {
     import std.file : DirEntry, dirEntries, isDir, isFile, SpanMode;
@@ -102,9 +148,12 @@ void walkDirs(string path)
     }
 }
 
+/++
+Prepare data file with the schema structure
++/
 void prepareDataFile()
 {
-    File file = File(dataFile, "w");
+    File file = File(DATA_FILE, "w");
     file.writeln("// This is an auto generated file, do not edit it!");
     file.writeln("module kuliya.data;");
     file.writeln();
@@ -147,17 +196,13 @@ void main()
 {
     try
     {
-        if (exists(dataFile))
-        {
-            remove(dataFile);
-        }
+        if (exists(DATA_FILE))
+            remove(DATA_FILE);
         prepareDataFile();
-        walkDirs(dataPath);
+        walkDirs(DATA_PATH);
     }
     catch (Exception e)
     {
-        import std.stdio : writeln;
-
         writeln("Error: ", e.msg);
         return;
     }