import sys, os
import argparse
from datetime import datetime
import json

# Check if the script is run with the correct arguments
parser = argparse.ArgumentParser(description="Generate event header files")
parser.add_argument('--output', required=True, help='Dir to write headers')
parser.add_argument('--input', required=True, help='Input directory containing event files')
args = parser.parse_args()

# Ensure outdir exists
outputFile = args.output
outputDir = args.output
os.makedirs(outputDir, exist_ok=True)

inputDir = args.input
# Scan for .json files in the input directory
if not os.path.exists(inputDir):
  print(f"Error: Input directory '{inputDir}' does not exist.")
  sys.exit(1)

jsonFiles = [f for f in os.listdir(inputDir) if f.endswith('.json')]
if not jsonFiles or len(jsonFiles) == 0:
  print(f"Error: No JSON files found in '{inputDir}'.")
  sys.exit(1)

# For each language file...
now = datetime.now().strftime("%Y-%m-%d %H:%M:%S")

eventFiles = []

for jsonFile in jsonFiles:
  inputFile = os.path.join(inputDir, jsonFile)
  data = json.load(open(inputFile, 'r', encoding='utf-8'))
  
  if 'key' not in data:
    print(f"Error: JSON file '{inputFile}' does not contain 'key' field.")
    sys.exit(1)

  if 'items' not in data or not isinstance(data['items'], list) or len(data['items']) == 0:
    print(f"Error: JSON file '{inputFile}' does not contain 'items' field.")
    sys.exit(1)

  key = data['key']
  keyUpper = key.upper()

  if jsonFile != f'{key}.json':
    print(f"Error: JSON file '{jsonFile}' does not match expected filename '{key}.json'.")
    sys.exit(1)
  
  outputFile = os.path.join(outputDir, f"{key}.h")

  with open(outputFile, 'w', encoding='utf-8') as f:
    f.write(f"// Generated event header for {jsonFile}\n")
    f.write(f"// Generated at {now}\n")
    f.write("#pragma once\n\n")
    f.write("#include \"event/eventdata.h\"\n\n")
    f.write(f"static const eventdata_t EVENT_{key.upper()} = {{\n")
    f.write(f"  .itemCount = {len(data['items'])},\n")
    f.write(f"  .items = {{\n")
    for i, item in enumerate(data['items']):
      if 'type' not in item:
        print(f"Error: Item {i} in '{jsonFile}' does not contain 'type' field.")
        sys.exit(1)
      
      itemType = item['type']
      f.write(f"    {{\n")

      # Text(s) Type
      if itemType == 'text':
        if 'text' not in item:
          print(f"Error: Item {i} in '{jsonFile}' of type 'text' does not contain 'text' field.")
          sys.exit(1)
        f.write(f"      .type = EVENT_TYPE_TEXT,\n")
        f.write(f"      .text = \"{item['text']}\",\n")


      else:
        print(f"Error: Unknown item type '{itemType}' in item {i} of '{jsonFile}'.")
        sys.exit(1)
      
      f.write(f"    }},\n")
    f.write(f"  }},\n")
    f.write(f"}};\n\n")

    eventFiles.append(key)

# Write the event list header
eventListFile = os.path.join(outputDir, "eventlist.h")
with open(eventListFile, 'w', encoding='utf-8') as f:
    f.write(f"// Generated event list header\n")
    f.write(f"// Generated at {now}\n")
    f.write("#pragma once\n\n")
    f.write("#include \"event/event.h\"\n")
    for event in eventFiles:
        f.write(f"#include \"event/{event}.h\"\n")
    f.write("\n")
    f.write(f"#define EVENT_LIST_COUNT {len(eventFiles)}\n\n")
    f.write("static const eventdata_t* EVENT_LIST[EVENT_LIST_COUNT] = {\n")
    for event in eventFiles:
        f.write(f"  &EVENT_{event.upper()},\n")
    f.write("};\n\n")