feat: implement automatic memory management and custom JSON serialization

- Add deinit() method to SearchResult for automatic memory management
- Implement custom jsonStringify() method to exclude allocator from JSON output
- Store allocator internally in SearchResult for automatic cleanup
- Simplify API: result.deinit() no longer requires allocator parameter
- Update all examples to use the new simplified API
- Remove dependency on external JSON formatting functions
- Update README.md with new usage patterns and Key Features section
- Fix JSON serialization errors in Zig 0.14.1
- All examples and tests now build and run successfully

Breaking changes:
- SearchResult.deinit() signature changed from deinit(allocator) to deinit()
- Removed formatSearchResultAsJson() and formatSearchResultAsPlainText() functions
- Users should now use std.json.stringify() directly with SearchResult

.github/copilot-instructions.md

@@ -33,3 +33,7 @@
 - The Pi-Finder library is focused on simplicity and performance
 - JSON is the standard output format
 - Any new features should maintain backward compatibility
+
+## Git Usage
+
+- Always use "git --no-pager" with commands that produce output, such as "git log", "git diff", etc.

README.md

@@ -5,11 +5,13 @@ A Zig library for searching numeric sequences in the decimal places of Pi.
 ## Features
 
 - Efficient searching of numeric sequences in Pi decimal places
-- JSON output as standard
-- Optional plain text output format
+- **Automatic memory management** with `result.deinit()`
+- **Custom JSON serialization** using `std.json.stringify`
+- JSON output as standard format
 - Configurable context display with delimiters
+- Performance metrics included in results
 - Reusable module design
-- Performance metrics
+- Compatible with Zig 0.14.1
 
 ## Installation
 
@@ -59,27 +61,74 @@ pub fn main() !void {
         .position = 25,
         .delimiter = "-",
         .delimiter_interval = 2,
+        .prefix = "[",
+        .suffix = "]",
     };
 
     // Search for sequence
     const result = try pi_finder.searchSequence("123456", context_config, allocator);
+    defer result.deinit(); // Automatically frees allocated memory
     
-    // Output as JSON (default format)
-    const json_output = try PiFinder.formatSearchResultAsJson(allocator, result);
-    defer allocator.free(json_output);
+    // Output as JSON using std.json.stringify
+    var json_string = std.ArrayList(u8).init(allocator);
+    defer json_string.deinit();
     
-    std.debug.print("{s}\n", .{json_output});
+    try std.json.stringify(result, .{}, json_string.writer());
+    std.debug.print("{s}\n", .{json_string.items});
 }
 ```
 
-### Using Plain Text Output Format
+### Plain Text Output Example
 
 ```zig
 // After getting the search result
-const plain_text_output = try PiFinder.formatSearchResultAsPlainText(allocator, result);
-defer allocator.free(plain_text_output);
+if (result.success) {
+    std.debug.print("Success: {}\n", .{result.success});
+    std.debug.print("Sequence: {s}\n", .{result.sequence});
+    if (result.position) |pos| {
+        std.debug.print("Position: {}\n", .{pos});
+    }
+    if (result.context) |context| {
+        std.debug.print("Context: {s}\n", .{context});
+    }
+} else {
+    std.debug.print("Search failed: {s}\n", .{result.error_message orelse "Unknown error"});
+}
+```
+
+## Key Features
+
+### Automatic Memory Management
+
+The library uses RAII (Resource Acquisition Is Initialization) pattern:
+
+```zig
+const result = try pi_finder.searchSequence("123456", context_config, allocator);
+defer result.deinit(); // Automatically frees allocated context memory
+```
+
+### Custom JSON Serialization
+
+SearchResult implements custom JSON serialization that excludes internal fields:
 
-std.debug.print("{s}\n", .{plain_text_output});
+```zig
+// The allocator field is automatically excluded from JSON output
+try std.json.stringify(result, .{}, writer);
+```
+
+### Performance Metrics
+
+Every search result includes detailed performance metrics:
+
+```json
+{
+  "performance": {
+    "file_load_time_ms": 327.988,
+    "search_time_ms": 10.766,
+    "file_size_mb": 953.674,
+    "load_speed_mbs": 2948.052
+  }
+}
 ```
 
 ## API
@@ -92,11 +141,6 @@ std.debug.print("{s}\n", .{plain_text_output});
 - `getContext(position, config, sequence, allocator)` - Generates context
 - `searchSequence(sequence, config, allocator)` - Comprehensive search with structured result
 
-### Output Format Functions
-
-- `formatSearchResultAsJson(allocator, result)` - Formats search result as JSON
-- `formatSearchResultAsPlainText(allocator, result)` - Formats search result as plain text
-
 ### ContextConfig
 
 Configuration for context display:
@@ -120,6 +164,11 @@ Structured result containing:
 - `performance` - Performance metrics
 - `context_config` - Used context configuration
 
+**Methods:**
+
+- `deinit()` - Frees any dynamically allocated memory (like context)
+- `jsonStringify(writer)` - Custom JSON serialization (automatically used by `std.json.stringify`)
+
 ## Examples
 
 See the `examples/` directory for complete examples:

examples/birth-date-finder/src/main.zig

@@ -1,5 +1,5 @@
 const std = @import("std");
-const PiFinder = @import("pi-finder");
+const pi = @import("pi-finder");
 
 pub fn main() !void {
     var gpa = std.heap.GeneralPurposeAllocator(.{}){};
@@ -10,7 +10,7 @@ pub fn main() !void {
     const pi_file_path = "../../data/pi-decimal-10_000_000_000.txt";
 
     // Initialize Pi Finder (JSON output is standard)
-    var pi_finder = PiFinder.PiFinder.init(allocator, pi_file_path) catch |err| {
+    var pi_finder = pi.PiFinder.init(allocator, pi_file_path) catch |err| {
         std.debug.print("Error initializing Pi finder: {}\n", .{err});
         return;
     };
@@ -20,7 +20,7 @@ pub fn main() !void {
     const birth_date = "010102"; // 01.01.02
 
     // Context configuration with delimiter '-'
-    const context_config = PiFinder.ContextConfig{
+    const context_config = pi.ContextConfig{
         .size = 50,
         .position = 25,
         .delimiter = "-",
@@ -31,18 +31,12 @@ pub fn main() !void {
 
     // Perform search
     const result = try pi_finder.searchSequence(birth_date, context_config, allocator);
+    defer result.deinit();
 
     // Output result as JSON
-    const json_output = try PiFinder.formatSearchResultAsJson(allocator, result);
+    const json_output = try pi.formatSearchResultAsJson(allocator, result);
     defer allocator.free(json_output);
 
     const stdout = std.io.getStdOut().writer();
     try stdout.print("{s}\n", .{json_output});
-
-    // Clean up if context was allocated
-    if (result.context) |context| {
-        if (context_config.delimiter != null) {
-            allocator.free(context);
-        }
-    }
 }

examples/birth-date-finder/src/plain_text_example.zig

@@ -33,6 +33,7 @@ pub fn main() !void {
 
     // Perform search
     const result = try pi_finder.searchSequence(birth_date, context_config, allocator);
+    defer result.deinit();
 
     // Output result as plain text
     const plain_text_output = try PiFinder.formatSearchResultAsPlainText(allocator, result);
@@ -40,11 +41,4 @@ pub fn main() !void {
 
     const stdout = std.io.getStdOut().writer();
     try stdout.print("{s}\n", .{plain_text_output});
-
-    // Clean up if context was allocated
-    if (result.context) |context| {
-        if (context_config.delimiter != null) {
-            allocator.free(context);
-        }
-    }
 }

examples/birth-date-finder/src/test_multiple.zig

@@ -41,6 +41,7 @@ pub fn main() !void {
 
         // Perform search
         const result = try pi_finder.searchSequence(birth_date, context_config, allocator);
+        defer result.deinit();
 
         // Output result as JSON
         const json_output = try PiFinder.formatSearchResultAsJson(allocator, result);
@@ -48,12 +49,5 @@ pub fn main() !void {
 
         const stdout = std.io.getStdOut().writer();
         try stdout.print("Searching for {s}:\n{s}\n\n", .{ birth_date, json_output });
-
-        // Clean up if context was allocated
-        if (result.context) |context| {
-            if (context_config.delimiter != null) {
-                allocator.free(context);
-            }
-        }
     }
 }

src/pi_finder.zig

@@ -22,6 +22,7 @@ pub const SearchResult = struct {
     error_message: ?[]const u8 = null,
     performance: ?PerformanceMetrics = null,
     context_config: ?ContextConfig = null,
+    allocator: ?std.mem.Allocator = null, // privates Feld, wird nicht serialisiert
 
     pub const PerformanceMetrics = struct {
         file_load_time_ms: f64,
@@ -29,6 +30,49 @@ pub const SearchResult = struct {
         file_size_mb: f64,
         load_speed_mbs: f64,
     };
+
+    /// Frees any dynamically allocated memory in the SearchResult
+    pub fn deinit(self: *const SearchResult) void {
+        if (self.allocator) |allocator| {
+            if (self.context) |context| {
+                allocator.free(context);
+            }
+        }
+    }
+
+    /// Custom JSON Serialisierung - ignoriert das allocator Feld
+    pub fn jsonStringify(self: @This(), writer: anytype) !void {
+        try writer.beginObject();
+
+        try writer.objectField("success");
+        try writer.write(self.success);
+
+        try writer.objectField("sequence");
+        try writer.write(self.sequence);
+
+        try writer.objectField("position");
+        try writer.write(self.position);
+
+        try writer.objectField("context");
+        try writer.write(self.context);
+
+        if (self.error_message != null) {
+            try writer.objectField("error_message");
+            try writer.write(self.error_message);
+        }
+
+        if (self.performance != null) {
+            try writer.objectField("performance");
+            try writer.write(self.performance);
+        }
+
+        if (self.context_config != null) {
+            try writer.objectField("context_config");
+            try writer.write(self.context_config);
+        }
+
+        try writer.endObject();
+    }
 };
 
 /// PiFinder structure with core functionality for searching and formatting sequences
@@ -187,6 +231,7 @@ pub const PiFinder = struct {
                 .position = null,
                 .context = null,
                 .error_message = @errorName(err),
+                .allocator = allocator,
             };
         };
 
@@ -202,6 +247,7 @@ pub const PiFinder = struct {
                     .position = pos,
                     .context = null,
                     .error_message = @errorName(err),
+                    .allocator = allocator,
                 };
             };
 
@@ -221,6 +267,7 @@ pub const PiFinder = struct {
                     .load_speed_mbs = load_speed_mbs,
                 },
                 .context_config = context_cfg,
+                .allocator = allocator,
             };
         } else {
             return SearchResult{
@@ -229,6 +276,7 @@ pub const PiFinder = struct {
                 .position = null,
                 .context = null,
                 .error_message = "Sequence not found in Pi",
+                .allocator = allocator,
             };
         }
     }