import os
from PIL import Image

def image_to_tspl_commands(image_path):
    """
    读取图片并转换为 TSPL 打印指令 (bytes)
    包含: SIZE, GAP, CLS, BITMAP, PRINT
    """
    if not os.path.exists(image_path):
        print(f"错误: 找不到图片 {image_path}")
        return None

    try:
        img = Image.open(image_path)
    except Exception as e:
        print(f"无法打开图片: {e}")
        return None

    # 处理透明背景
    if img.mode in ('RGBA', 'LA') or (img.mode == 'P' and 'transparency' in img.info):
        alpha = img.convert('RGBA').split()[-1]
        bg = Image.new("RGBA", img.size, (255, 255, 255, 255))
        bg.paste(img, mask=alpha)
        img = bg

    # 目标尺寸: 48mm x 30mm @ 203dpi
    # 宽度: 48 * 8 = 384 dots
    # 高度: 30 * 8 = 240 dots
    MAX_WIDTH = 384
    MAX_HEIGHT = 240
    
    # 使用 thumbnail 进行等比缩放，确保不超过最大尺寸
    img.thumbnail((MAX_WIDTH, MAX_HEIGHT), Image.Resampling.LANCZOS)
    
    target_width, target_height = img.size
    print(f"图片缩放后尺寸: {target_width}x{target_height}")
    
    # 转为二值图
    # 1. 先转灰度
    img = img.convert('L')
    # 2. 二值化 (使用默认的抖动算法)
    img = img.convert('1')
    
    # 构造 BITMAP 数据
    width_bytes = (target_width + 7) // 8
    data = bytearray()
    
    # 遍历像素生成数据
    # TSPL BITMAP 数据: 1=Black(Print), 0=White(No Print)
    # PIL '1' mode: 0=Black, 255=White
    
    for y in range(target_height):
        row_bytes = bytearray(width_bytes)
        for x in range(target_width):
            pixel = img.getpixel((x, y))
            
            # 逻辑修正:
            # 我们希望 黑色像素(0) -> 打印(1)
            # 白色像素(255) -> 不打印(0)
            
            should_print = False
            if pixel == 0: # Black
                should_print = True
            
            if should_print:
                byte_index = x // 8
                bit_index = 7 - (x % 8)
                row_bytes[byte_index] |= (1 << bit_index)
        
        data.extend(row_bytes)
        
    # 计算居中偏移
    x_offset = (MAX_WIDTH - target_width) // 2
    y_offset = (MAX_HEIGHT - target_height) // 2
    
    # 生成指令
    cmds = bytearray()
    
    # 1. 初始化
    # CLS
    cmds.extend(b"CLS\r\n")
    # SIZE 48 mm, 30 mm
    cmds.extend(b"SIZE 48 mm, 30 mm\r\n")
    # GAP 2 mm, 0 mm
    cmds.extend(b"GAP 2 mm, 0 mm\r\n")
    # HOME
    cmds.extend(b"HOME\r\n")
    
    # 2. BITMAP
    # BITMAP x, y, width_bytes, height, mode, data
    header = f"BITMAP {x_offset},{y_offset},{width_bytes},{target_height},0,".encode('utf-8')
    cmds.extend(header)
    cmds.extend(data)
    cmds.extend(b"\r\n") # BITMAP data 后面通常不需要回车，但有些文档建议加? 不，binary data后紧跟下一个指令
    # TSPL protocol says: BITMAP ... data ... CR LF is NOT required after data, but next command must start.
    # Usually it's safer to just send data.
    
    # 3. PRINT
    cmds.extend(b"PRINT 1\r\n")
    
    return cmds

def generate_micropython_printer_script(image_path, output_py_path):
    """
    保留此函数以兼容现有 workflow，但内部使用新的逻辑
    """
    cmds = image_to_tspl_commands(image_path)
    if not cmds:
        return

    # 提取 BITMAP 数据部分用于生成脚本 (因为脚本里是用 uart.write 分段发送的)
    # 为了简单，我们重新解析一下 cmds 或者直接重写这部分逻辑
    # 但为了脚本的可读性，还是像之前一样生成
    
    # 重新执行一遍核心逻辑来获取参数 (为了生成漂亮的 python 代码)
    if not os.path.exists(image_path): return
    img = Image.open(image_path)
    if img.mode in ('RGBA', 'LA') or (img.mode == 'P' and 'transparency' in img.info):
        alpha = img.convert('RGBA').split()[-1]
        bg = Image.new("RGBA", img.size, (255, 255, 255, 255))
        bg.paste(img, mask=alpha)
        img = bg
        
    MAX_WIDTH = 384
    MAX_HEIGHT = 240
    img.thumbnail((MAX_WIDTH, MAX_HEIGHT), Image.Resampling.LANCZOS)
    target_width, target_height = img.size
    img = img.convert('L').convert('1')
    
    width_bytes = (target_width + 7) // 8
    data = bytearray()
    for y in range(target_height):
        row_bytes = bytearray(width_bytes)
        for x in range(target_width):
            if img.getpixel((x, y)) == 0:
                byte_index = x // 8
                bit_index = 7 - (x % 8)
                row_bytes[byte_index] |= (1 << bit_index)
        data.extend(row_bytes)
        
    x_offset = (MAX_WIDTH - target_width) // 2
    y_offset = (MAX_HEIGHT - target_height) // 2
    
    hex_data = data.hex()
    
    script_content = f'''from machine import UART
import time
from config import ttl_tx, ttl_rx
from printer_driver import TsplPrinter
import ubinascii

# ==============================================================================
# 图片打印脚本 (自动生成)
# ==============================================================================
# 图片来源: {image_path}
# ==============================================================================

# 1. 初始化
uart = UART(1, baudrate=115200, tx=ttl_tx, rx=ttl_rx)
printer = TsplPrinter(uart)

def print_image():
    print("=== 开始打印图片 ===")
    
    # 2. 设置标签
    printer.cls()
    printer.size(48, 30)
    printer.gap(2, 0)
    
    # 3. 准备图片数据
    img_hex = "{hex_data}"
    img_data = ubinascii.unhexlify(img_hex)
    
    # 4. 发送 BITMAP 指令
    print(f"正在发送图片数据 ({{len(img_data)}} bytes)...")
    
    # BITMAP X, Y, width_bytes, height, mode, data
    # 居中打印
    cmd = f"BITMAP {x_offset},{y_offset},{width_bytes},{target_height},0,".encode('utf-8')
    uart.write(cmd)
    
    chunk_size = 128
    for i in range(0, len(img_data), chunk_size):
        uart.write(img_data[i : i + chunk_size])
        time.sleep(0.005)
        
    uart.write(b'\\r\\n')
    
    # 5. 打印
    printer.print_out(1)
    print("打印完成")

if __name__ == "__main__":
    try:
        print_image()
    except Exception as e:
        print(f"错误: {{e}}")
'''

    with open(output_py_path, 'w', encoding='utf-8') as f:
        f.write(script_content)
    
    print(f"成功生成 MicroPython 脚本: {output_py_path}")

if __name__ == "__main__":
    generate_micropython_printer_script(
        "/Users/jeremygan/Desktop/python_dev/V2_micropython/test_image.png",
        "/Users/jeremygan/Desktop/python_dev/V2_micropython/printer_image_print.py"
    )