fix json export

radar_data_reader/core/app_controller.py

@@ -6,12 +6,13 @@ Orchestrates the interaction between the GUI and the core processing logic.
 """
 import multiprocessing as mp
 import csv
+import json
 import os
 import subprocess
 import sys
 from pathlib import Path
 from typing import List, Any, Dict, Tuple, Optional
-from tkinter import filedialog
+from tkinter import filedialog, messagebox
 import tkinter as tk
 
 from ..utils.config_manager import ConfigManager
@@ -46,10 +47,6 @@ def _get_value_from_path(batch: DataBatch, field: ExportField) -> Any:
         log.warning(f"Could not find attribute for path: {path}")
         return "N/A"
 
-def _write_json_row(file_handle, row_dict: Dict[str, Any]):
-    # Helper to write a JSON object to a file, followed by a newline.
-    json.dump(row_dict, file_handle)
-    file_handle.write("\n")
 
 class AppController:
     """The main controller of the application."""
@@ -66,6 +63,9 @@ class AppController:
         self.output_file_handles: Dict[str, Any] = {}
         self.csv_writers: Dict[str, Any] = {}
         
+        # Buffer for JSON data
+        self.json_data_buffer: List[Dict[str, Any]] = []
+        
         self.last_generated_out_file: Optional[Path] = None
 
     def bind_view(self, view):
@@ -132,10 +132,13 @@ class AppController:
         self.output_file_handles.clear()
         self.csv_writers.clear()
         self.active_export_profiles.clear()
+        self.json_data_buffer.clear() # Clear JSON buffer
+        
         try:
             output_dir = Path(self.view.out_output_dir_var.get())
             basename = self.view.out_basename_var.get()
             profiles = self.config_manager.get_export_profiles()
+            
             if self.view.out_output_csv_var.get():
                 profile = next((p for p in profiles if p.name == self.view.out_csv_profile_var.get()), None)
                 if not profile: raise ValueError(f"CSV profile '{self.view.out_csv_profile_var.get()}' not found.")
@@ -145,12 +148,13 @@ class AppController:
                 self.output_file_handles["csv"] = fh
                 self.csv_writers["csv"] = csv.writer(fh)
                 self.csv_writers["csv"].writerow([f.column_name for f in profile.fields])
+            
             if self.view.out_output_json_var.get():
                 profile = next((p for p in profiles if p.name == self.view.out_json_profile_var.get()), None)
                 if not profile: raise ValueError(f"JSON profile '{self.view.out_json_profile_var.get()}' not found.")
                 self.active_export_profiles["json"] = profile
-                path = (output_dir / basename).with_suffix(".json")
+                # JSON file is no longer opened here, it's written at the end.
-                self.output_file_handles["json"] = open(path, "w", encoding="utf-8")
+            
             return True
         except (IOError, ValueError) as e:
             log.error(f"Failed to prepare output files: {e}")
@@ -175,7 +179,6 @@ class AppController:
         self.config_manager.set("active_out_export_profile_name", self.view.out_csv_profile_var.get())
         self.config_manager.save_config()
         
-        # --- CORRECTED LINE ---
         active_profile = self.active_export_profiles.get("csv") or self.active_export_profiles.get("json")
         worker_args = (Path(filepath_str), self.command_queue, self.result_queue, active_profile)
         self._launch_worker(run_worker_process, worker_args)
@@ -213,7 +216,7 @@ class AppController:
             output_dir = self.view.rec_output_dir_var.get()
         except ValueError as e:
             log.error(f"Configuration error: {e}")
-            tk.messagebox.showerror("Configuration Error", str(e), parent=self.view)
+            messagebox.showerror("Configuration Error", str(e), parent=self.view)
             return
             
         self.is_processing = True
@@ -241,20 +244,42 @@ class AppController:
         self.csv_writers.clear()
 
     def handle_data_batch(self, batch: DataBatch):
-        """Writes a data batch to the currently open output files (CSV/JSON)."""
+        """Writes a data batch to CSV and buffers it for JSON."""
         if self.csv_writers.get("csv"):
             profile = self.active_export_profiles["csv"]
             row_values = [_get_value_from_path(batch, field) for field in profile.fields]
             self.csv_writers["csv"].writerow(row_values)
 
-        if self.output_file_handles.get("json"):
+        if "json" in self.active_export_profiles:
             profile = self.active_export_profiles["json"]
             row_dict = {field.column_name: _get_value_from_path(batch, field) for field in profile.fields}
-            _write_json_row(self.output_file_handles["json"], row_dict)
+            self.json_data_buffer.append(row_dict)
 
         if batch.batch_id % 20 == 0:
-            for fh in self.output_file_handles.values():
+            if "csv" in self.output_file_handles:
-                fh.flush()
+                self.output_file_handles["csv"].flush()
+    
+    def _write_json_buffer_to_file(self):
+        """Writes the buffered JSON data to a file."""
+        if not self.json_data_buffer:
+            if "json" in self.active_export_profiles:
+                log.info("JSON export was enabled, but no data batches were generated. Skipping file creation.")
+            return
+
+        try:
+            output_dir = Path(self.view.out_output_dir_var.get())
+            basename = self.view.out_basename_var.get()
+            path = (output_dir / basename).with_suffix(".json")
+            
+            log.info(f"Writing {len(self.json_data_buffer)} records to JSON file: {path}")
+            with open(path, "w", encoding="utf-8") as f:
+                json.dump(self.json_data_buffer, f, indent=4)
+            log.info("JSON file written successfully.")
+
+        except (IOError, ValueError) as e:
+            log.error(f"Failed to write JSON output file: {e}")
+        finally:
+            self.json_data_buffer.clear()
 
     def open_folder_from_path(self, folder_path_str: str):
         if not folder_path_str: return
@@ -270,6 +295,11 @@ class AppController:
     def handle_worker_completion(self, msg: Dict[str, Any]):
         status = "Interrupted" if msg.get("interrupted") else "Complete"
         log.info(f"--- Process {status}. ---")
+        
+        # Write buffered JSON data before closing files
+        if self.view.out_output_json_var.get():
+            self._write_json_buffer_to_file()
+            
         self._close_all_files()
         self.is_processing = False
         self.worker_process = None