package cn.iocoder.yudao.module.crm.service.quotation;

import cn.hutool.core.convert.Convert;
import cn.iocoder.yudao.module.crm.controller.admin.quotation.vo.CrmSaleQuotationRespVO;
import org.springframework.core.io.ClassPathResource;
import org.w3c.dom.Node;

import javax.imageio.ImageIO;
import javax.xml.XMLConstants;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import java.awt.*;
import java.awt.geom.Path2D;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.math.BigDecimal;
import java.math.RoundingMode;
import java.time.format.DateTimeFormatter;
import java.util.HashMap;
import java.util.Map;
import java.util.Objects;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;

/**
 * 销售报价单 Word 导出：基于 {@code templates/quotation/sale-quotation.docx} 模板填写业务槽位，
 * 并在导出时按公司名称实时绘制电子章（不依赖静态章图片资源）。
 */
public final class CrmSaleQuotationDocumentRenderer {

    private static final String W = "http://schemas.openxmlformats.org/wordprocessingml/2006/main";
    private static final String TEMPLATE = "templates/quotation/sale-quotation.docx";
    private static final String SEAL_ENTRY = "word/media/seal.png";

    private CrmSaleQuotationDocumentRenderer() {
    }

    public static byte[] render(CrmSaleQuotationRespVO quotation, String companyName) throws IOException {
        if (quotation == null) {
            throw new IllegalArgumentException("报价单不存在，无法生成报价文件");
        }
        if (quotation.getItems() == null || quotation.getItems().isEmpty()) {
            throw new IllegalArgumentException("报价单没有产品明细，无法生成报价文件");
        }
        byte[] seal = renderSeal(companyName);
        try (var input = new ClassPathResource(TEMPLATE).getInputStream();
             var zip = new ZipInputStream(input);
             var output = new ByteArrayOutputStream();
             var result = new ZipOutputStream(output)) {
            ZipEntry entry;
            while ((entry = zip.getNextEntry()) != null) {
                byte[] content = zip.readAllBytes();
                if ("word/document.xml".equals(entry.getName())) {
                    content = fillDocument(content, quotation, companyName);
                } else if (SEAL_ENTRY.equals(entry.getName())) {
                    content = seal;
                }
                result.putNextEntry(new ZipEntry(entry.getName()));
                result.write(content);
                result.closeEntry();
            }
            result.finish();
            return output.toByteArray();
        }
    }

    private static byte[] fillDocument(byte[] xml, CrmSaleQuotationRespVO quotation, String companyName)
            throws IOException {
        try {
            var factory = DocumentBuilderFactory.newInstance();
            factory.setNamespaceAware(true);
            factory.setFeature("http://apache.org/xml/features/disallow-doctype-decl", true);
            factory.setAttribute(XMLConstants.ACCESS_EXTERNAL_DTD, "");
            factory.setAttribute(XMLConstants.ACCESS_EXTERNAL_SCHEMA, "");
            var document = factory.newDocumentBuilder().parse(new ByteArrayInputStream(xml));

            // 1. 产品明细行
            Node rowTemplate = null;
            var rows = document.getElementsByTagNameNS(W, "tr");
            for (int i = 0; i < rows.getLength(); i++) {
                if (rows.item(i).getTextContent().contains("${itemName}")) {
                    rowTemplate = rows.item(i);
                    break;
                }
            }
            if (rowTemplate == null) {
                throw new IOException("报价单模板缺少产品明细槽位");
            }
            int index = 0;
            for (var item : quotation.getItems()) {
                Node row = rowTemplate.cloneNode(true);
                BigDecimal price = item.getQuotationPrice() == null ? BigDecimal.ZERO : item.getQuotationPrice();
                BigDecimal count = item.getCount() == null ? BigDecimal.ZERO : item.getCount();
                BigDecimal amount = item.getTotalPrice() != null ? item.getTotalPrice()
                        : price.multiply(count).setScale(2, RoundingMode.HALF_UP);
                String name = text(item.getItemName());
                if (name.isBlank()) {
                    name = text(item.getItemCode());
                }
                Map<String, String> values = new HashMap<>();
                values.put("index", String.valueOf(++index));
                values.put("itemName", name);
                values.put("itemSpecification", text(item.getItemSpecification()));
                values.put("unitName", text(item.getItemUnitName()));
                values.put("count", count.stripTrailingZeros().toPlainString());
                values.put("price", money(price));
                values.put("amount", money(amount));
                replace(row, values);
                rowTemplate.getParentNode().insertBefore(row, rowTemplate);
            }
            rowTemplate.getParentNode().removeChild(rowTemplate);

            // 2. 表头与金额
            BigDecimal productTotal = quotation.getTotalProductPrice() == null ? BigDecimal.ZERO
                    : quotation.getTotalProductPrice();
            BigDecimal discount = quotation.getDiscountPrice() == null ? BigDecimal.ZERO
                    : quotation.getDiscountPrice();
            BigDecimal taxRate = quotation.getTaxRate() == null ? BigDecimal.ZERO : quotation.getTaxRate();
            BigDecimal taxPrice = quotation.getTaxPrice() == null ? BigDecimal.ZERO : quotation.getTaxPrice();
            BigDecimal total = quotation.getTotalPrice() == null ? BigDecimal.ZERO : quotation.getTotalPrice();
            Map<String, String> values = new HashMap<>();
            values.put("companyName", text(companyName));
            values.put("customerName", text(quotation.getCustomerName()));
            values.put("quotationNo", text(quotation.getNo()));
            values.put("quotationName", text(quotation.getName()));
            values.put("quotationDate", date(quotation.getQuotationTime()));
            values.put("validUntil", date(quotation.getValidUntil()));
            values.put("contactName", text(quotation.getContactName()));
            values.put("ownerUserName", text(quotation.getOwnerUserName()));
            values.put("productTotal", money(productTotal));
            values.put("discountPrice", money(discount));
            values.put("taxRate", taxRate.stripTrailingZeros().toPlainString());
            values.put("taxPrice", money(taxPrice));
            values.put("totalPrice", money(total));
            values.put("totalUpper", Convert.digitToChinese(total));
            values.put("remark", text(quotation.getRemark()).isBlank() ? "无" : quotation.getRemark());
            replace(document, values);
            if (document.getDocumentElement().getTextContent().contains("${")) {
                throw new IOException("报价单模板存在未填写槽位");
            }

            var transformerFactory = TransformerFactory.newInstance();
            transformerFactory.setAttribute(XMLConstants.ACCESS_EXTERNAL_DTD, "");
            transformerFactory.setAttribute(XMLConstants.ACCESS_EXTERNAL_STYLESHEET, "");
            var output = new ByteArrayOutputStream();
            transformerFactory.newTransformer().transform(new DOMSource(document), new StreamResult(output));
            return output.toByteArray();
        } catch (IOException exception) {
            throw exception;
        } catch (Exception exception) {
            throw new IOException("生成报价单 Word 文件失败", exception);
        }
    }

    // ==================== 电子章绘制 ====================

    /**
     * 按公司名称实时绘制红色圆形电子章：双圆环 + 上方环绕公司名 + 中央五角星 + 下方“报价专用章”。
     * 不依赖任何静态章图片，避免换公司品牌后仍需单独维护图片资源。
     */
    static byte[] renderSeal(String companyName) throws IOException {
        int size = 400;
        var image = new BufferedImage(size, size, BufferedImage.TYPE_INT_ARGB);
        Graphics2D g = image.createGraphics();
        try {
            g.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
            g.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);
            var red = new Color(200, 16, 46);
            g.setColor(red);
            g.setStroke(new BasicStroke(9f));
            g.drawOval(12, 12, size - 24, size - 24);
            g.setStroke(new BasicStroke(3f));
            g.drawOval(38, 38, size - 76, size - 76);

            String name = text(companyName).isBlank() ? "公司" : companyName.trim();
            int fontSize = Math.max(16, Math.min(30, 560 / Math.max(1, name.length())));
            g.setFont(new Font("SimSun", Font.BOLD, fontSize));
            drawArcText(g, name, size / 2, size / 2, size / 2 - 62, 195, 150);

            drawStar(g, size / 2, size / 2 - 8, 34, 14);
            g.setFont(new Font("SimSun", Font.BOLD, 27));
            drawCentered(g, "报价专用章", size / 2, (int) (size * 0.68));
        } finally {
            g.dispose();
        }
        var output = new ByteArrayOutputStream();
        ImageIO.write(image, "png", output);
        return output.toByteArray();
    }

    /** 沿圆弧排布文字，startDeg 起、顺时针 sweepDeg 度；字符基线朝圆心。 */
    private static void drawArcText(Graphics2D g, String text, int cx, int cy, int radius,
                                    double startDeg, double sweepDeg) {
        FontMetrics fm = g.getFontMetrics();
        int[] widths = new int[text.length()];
        double totalWidth = 0;
        for (int i = 0; i < text.length(); i++) {
            widths[i] = Math.max(1, fm.charWidth(text.charAt(i)));
            totalWidth += widths[i];
        }
        double angle = startDeg;
        for (int i = 0; i < text.length(); i++) {
            double span = widths[i] / totalWidth * sweepDeg;
            double center = angle + span / 2;
            double rad = Math.toRadians(center);
            int x = (int) (cx + radius * Math.cos(rad));
            int y = (int) (cy + radius * Math.sin(rad));
            var transform = g.getTransform();
            g.rotate(Math.toRadians(center + 90), x, y);
            g.drawString(String.valueOf(text.charAt(i)), x - widths[i] / 2, y + fm.getAscent() / 2 - 3);
            g.setTransform(transform);
            angle += span;
        }
    }

    private static void drawStar(Graphics2D g, int cx, int cy, int outer, int inner) {
        var path = new Path2D.Double();
        for (int i = 0; i < 10; i++) {
            double r = i % 2 == 0 ? outer : inner;
            double angle = Math.toRadians(-90 + i * 36);
            double x = cx + r * Math.cos(angle);
            double y = cy + r * Math.sin(angle);
            if (i == 0) {
                path.moveTo(x, y);
            } else {
                path.lineTo(x, y);
            }
        }
        path.closePath();
        g.fill(path);
    }

    private static void drawCentered(Graphics2D g, String text, int cx, int baseline) {
        FontMetrics fm = g.getFontMetrics();
        g.drawString(text, cx - fm.stringWidth(text) / 2, baseline);
    }

    // ==================== 工具方法 ====================

    private static void replace(Node node, Map<String, String> values) {
        if (node.getNodeType() == Node.ELEMENT_NODE && "t".equals(node.getLocalName())
                && W.equals(node.getNamespaceURI())) {
            String value = node.getTextContent();
            for (var entry : values.entrySet()) {
                value = value.replace("${" + entry.getKey() + "}", entry.getValue());
            }
            node.setTextContent(value);
            return;
        }
        for (Node child = node.getFirstChild(); child != null; child = child.getNextSibling()) {
            replace(child, values);
        }
    }

    private static String money(BigDecimal value) {
        return value.setScale(2, RoundingMode.HALF_UP).toPlainString();
    }

    private static String date(java.time.LocalDateTime value) {
        return value == null ? "____________" : value.format(DateTimeFormatter.ofPattern("yyyy年MM月dd日"));
    }

    private static String text(String value) {
        return Objects.requireNonNullElse(value, "");
    }
}