import json
from processimage import processImage
import sys
from assethelpers import getAssetRelativePath
import os
import datetime
from args import args

def processTileset(asset):
  print(f"Processing tileset: {asset['path']}")

  # We need to determine how big each tile is. This can either be provided as
  # an arg of tileWidth/tileHeight or as a count of rows/columns.
  # Additionally, if the image has been factored, then the user can provide both
  # tile sizes AND cols/rows to indicate the original size of the image.

  image = processImage(asset)

  tileWidth, tileHeight = None, None
  columns, rows = None, None
  originalWidth, originalHeight = image['width'], image['height']

  if 'tileWidth' in asset['options'] and 'columns' in asset['options']:
    tileWidth = int(asset['options']['tileWidth'])
    columns = int(asset['options']['columns'])
    originalWidth = tileWidth * columns
  elif 'tileWidth' in asset['options']:
    tileWidth = int(asset['options']['tileWidth'])
    columns = image['width'] // tileWidth
  elif 'columns' in asset['options']:
    columns = int(asset['options']['columns'])
    tileWidth = image['width'] // columns
  else:
    print(f"Error: Tileset {asset['path']} must specify either tileWidth or columns")
    sys.exit(1)

  if 'tileHeight' in asset['options'] and 'rows' in asset['options']:
    tileHeight = int(asset['options']['tileHeight'])
    rows = int(asset['options']['rows'])
    originalHeight = tileHeight * rows
  elif 'tileHeight' in asset['options']:
    tileHeight = int(asset['options']['tileHeight'])
    rows = image['height'] // tileHeight
  elif 'rows' in asset['options']:
    rows = int(asset['options']['rows'])
    tileHeight = image['height'] // rows
  else:
    print(f"Error: Tileset {asset['path']} must specify either tileHeight or rows")
    sys.exit(1)
  
  fileNameWithoutExtension = os.path.splitext(os.path.basename(asset['path']))[0]
  now = datetime.datetime.now().strftime("%Y-%m-%d %H:%M:%S")
  tilesetName = fileNameWithoutExtension
  tilesetNameUpper = tilesetName.upper()

  widthScale = originalWidth / image['width']
  heightScale = originalHeight / image['height']

  # Create header
  data = f"// Tileset Generated for {asset['path']} at {now}\n"
  data += f"#pragma once\n"
  data += f"#include \"display/tileset.h\"\n\n"
  data += f"static const tileset_t TILESET_{tilesetNameUpper} = {{\n"
  data += f"  .tileWidth = {tileWidth},\n"
  data += f"  .tileHeight = {tileHeight},\n"
  data += f"  .tileCount = {columns * rows},\n"
  data += f"  .columns = {columns},\n"
  data += f"  .rows = {rows},\n"
  data += f"  .uv = {{ {widthScale / columns}f, {heightScale / rows}f }},\n"
  data += f"  .image = {json.dumps(image['imagePath'])},\n"
  data += f"}};\n"

  # Write Header
  outputFile = os.path.join(args.headers_dir, "display", "tileset", f"tileset_{tilesetName}.h")
  os.makedirs(os.path.dirname(outputFile), exist_ok=True)
  with open(outputFile, 'w') as f:
    f.write(data)
  
  outTileset = {
    "image": image,
    "headerFile": outputFile,
    "files": image['files'],
  }
  return outTileset