game-cards-poker-design/backend/apps/exports/utils.py

from PIL import Image, ImageDraw
import io
import os


def load_image(file_path, scale=1):
    """加载图片并应用缩放"""
    img = Image.open(file_path).convert('RGBA')

    if scale > 1:
        new_size = (int(img.width * scale), int(img.height * scale))
        img = img.resize(new_size, Image.LANCZOS)

    return img


def generate_symmetrical_face_card(original_image_path, scale=1):
    """
    生成JQK中心对称图案
    输入：原始图片路径
    输出：中心对称的图像数组（上半部分、下半部分）
    """
    original = load_image(original_image_path, scale)
    width, height = original.size
    half_height = height // 2

    # 创建上半部分
    top_half = original.crop((0, 0, width, half_height))

    # 创建下半部分并翻转
    bottom_half = original.crop((0, half_height, width, height))
    bottom_half = bottom_half.transpose(Image.FLIP_TOP_BOTTOM)

    return top_half, bottom_half


def render_background(canvas, layer, scale):
    """渲染背景层"""
    if layer.properties:
        properties = layer.properties
        width = canvas.size[0]
        height = canvas.size[1]

        # 解析color（如 '#FF0000' 或 'rgb(255,0,0)'）
        bg_color = properties.get('color', '#FFFFFF')

        # 创建背景矩形
        draw = ImageDraw.Draw(canvas, 'RGBA')
        draw.rectangle(((0, 0), (width, height)), fill=bg_color + 'FF')

        # 如果有纹理或图案路径
        texture_path = properties.get('texture_path')
        if texture_path and os.path.exists(texture_path):
            texture = load_image(texture_path, scale)
            bg_height = height // 4
            for y in range(0, height, bg_height):
                canvas.paste(texture, (0, y), texture)


def render_image_layer(canvas, project, layer, scale):
    """渲染图片层（人像、花色等）"""
    if not layer.file_ref or not layer.file_ref.file_path:
        return

    asset_path = os.path.join(project.media_root, layer.file_ref.file_path)

    if not os.path.exists(asset_path):
        return

    image = load_image(asset_path, scale)

    # 获取位置信息
    properties = layer.properties or {}
    x = properties.get('x', 0)
    y = properties.get('y', 0)
    width = properties.get('width', image.size[0])
    height = properties.get('height', image.size[1])

    # 计算实际坐标
    canvas_width, canvas_height = canvas.size
    actual_x = (x / project.card_width) * canvas_width
    actual_y = (y / project.card_height) * canvas_height

    # 计算实际尺寸
    actual_w = (width / project.card_width) * canvas_width
    actual_h = (height / project.card_height) * canvas_height

    # 裁剪图片
    cropped = image.copy()
    cropped.thumbnail((actual_w, actual_h), Image.LANCZOS)

    # 计算居中位置
    paste_x = actual_x + (actual_w - cropped.size[0]) / 2
    paste_y = actual_y + (actual_h - cropped.size[1]) / 2

    canvas.paste(cropped, (int(paste_x), int(paste_y)), cropped)


def render_text_layer(canvas, layer, scale):
    """渲染文字层"""
    properties = layer.properties or {}

    draw = ImageDraw.Draw(canvas, 'RGBA')

    text = properties.get('text', '')
    x = properties.get('x', 0)
    y = properties.get('y', 0)

    # 解析字体和颜色
    font = properties.get('font', None)
    if font and isinstance(font, dict):
        font_size = int(font.get('size', 24) * scale)
        font_path = font.get('path')

        from PIL import ImageFont
        if font_path and os.path.exists(font_path):
            try:
                custom_font = ImageFont.truetype(font_path, font_size)
            except:
                custom_font = None
        else:
            custom_font = None
    else:
        from PIL import ImageFont
        custom_font = ImageFont.load_default()

    # 转换颜色
    color = properties.get('color', '#000000')
    if color.startswith('#'):
        r = int(color[1:3], 16)
        g = int(color[3:5], 16)
        b = int(color[5:7], 16)
        fill = (r, g, b, 255)
    else:
        fill = (0, 0, 0, 255)

    # 计算实际坐标和尺寸
    canvas_width, canvas_height = canvas.size
    actual_x = (x / project.card_width) * canvas_width
    actual_y = (y / project.card_height) * canvas_height

    bbox = draw.textbbox((0, 0), text, font=custom_font)
    text_width = bbox[2] - bbox[0]
    text_height = bbox[3] - bbox[1]

    # 居中计算
    paste_x = actual_x + (canvas_width * project.card_width * 0.3 - text_width) / 2
    paste_y = actual_y + (canvas_height * project.card_height * 0.5 - text_height) / 2

    draw.text((int(paste_x), int(paste_y)), text, font=custom_font, fill=fill)


def generate_card_png(project, card_key, resolution='standard', scale_map={ 'standard': 1, 'hd': 2, 'ultra-hd': 4 }):
    """
    生成单张牌的PNG图片

    Args:
        project: Project对象
        card_key: 牌面key（如'hearts-A', 'spades-K', 'joker-big'）
        resolution: 分辨率（standard/hd/ultra-hd）
        scale_map: 分辨率对应的缩放比例

    Returns:
        Image对象
    """
    scale = scale_map.get(resolution, 1)

    # 创建基础画布
    # 牌面坐标系
    x_offset = int(50 * scale)
    y_offset = int(50 * scale)
    draw_width = int((project.card_width - 100) * scale)
    draw_height = int((project.card_height - 100) * scale)

    canvas = Image.new('RGBA', (draw_width, draw_height))
    draw = ImageDraw.Draw(canvas, 'RGBA')
    draw.rectangle(((0, 0), (draw_width, draw_height)), fill=(255, 255, 255, 255))

    # 获取卡片类型的所有图层
    layers = CardLayer.objects.filter(
        project=project,
        card_key=card_key,
        visible=True
    ).order_by('z_index')

    # 渲染各图层
    for layer in layers:
        layer_type = layer.layer_type
        if layer_type == 'background':
            render_background(canvas, layer, scale)
        elif layer_type == 'image':
            render_image_layer(canvas, project, layer, scale)
        elif layer_type == 'text':
            render_text_layer(canvas, layer, scale)

    return canvas