yy-admin-master/YY.Admin/Views/Print/PrintPreviewWindow.xaml.cs

using System.Text.Json;
using System.Text.Json.Nodes;
using System.Text.RegularExpressions;
using System.Windows;
using YY.Admin.Core.Entity;
using YY.Admin.Services.Service.Print;

namespace YY.Admin.Views.Print;

public partial class PrintPreviewWindow : HandyControl.Controls.Window
{
    private readonly string _templateJson;

    public PrintPreviewWindow(PrintTemplate template, string? templateJson)
    {
        InitializeComponent();
        _templateJson = templateJson ?? string.Empty;

        TbTemplateName.Text = template.TemplateName ?? "（未命名）";
        TbTemplateCode.Text = $"编码：{template.TemplateCode}  " +
                              $"尺寸：{template.PaperWidthMm ?? 210}×{template.PaperHeightMm ?? 297} mm  " +
                              $"方向：{template.PaperOrientation ?? "纵向"}";

        TbParamJson.Text = BuildMockParamJson(_templateJson);

        Loaded += async (_, _) => await LoadPreviewAsync();
    }

    private async Task LoadPreviewAsync()
    {
        try
        {
            TbStatus.Text = "加载中…";
            await WebView.EnsureCoreWebView2Async();

            if (string.IsNullOrWhiteSpace(_templateJson) || _templateJson == "{}")
            {
                WebView.NavigateToString(BuildEmptyHtml());
                TbStatus.Text = "尚未设计模板内容";
                return;
            }

            await RenderCurrentParamJsonAsync();
        }
        catch (Exception ex)
        {
            TbStatus.Text = $"预览失败：{ex.Message}";
        }
    }

    private static string BuildEmptyHtml() => """
        <!DOCTYPE html>
        <html><head><meta charset="utf-8"/>
        <style>
          body { margin:0; background:#525659; display:flex;
                 align-items:center; justify-content:center; height:100vh;
                 font-family:"Microsoft YaHei",Arial,sans-serif; }
          .card { background:#fff; border-radius:8px; padding:48px 64px;
                  text-align:center; box-shadow:0 6px 24px rgba(0,0,0,.4); }
          .icon { font-size:48px; color:#ccc; margin-bottom:16px; }
          .tip  { font-size:15px; color:#888; }
        </style></head>
        <body>
          <div class="card">
            <div class="icon">📄</div>
            <div class="tip">该模板尚未设计内容</div>
          </div>
        </body></html>
        """;

    /// <summary>
    /// 左侧参数 JSON 重新渲染预览（与后端预览一致：用参数 JSON 驱动模板绑定字段）。
    /// </summary>
    private async Task RenderCurrentParamJsonAsync()
    {
        try
        {
            TbStatus.Text = "渲染中…";

            JsonObject dataObj;
            var text = TbParamJson.Text?.Trim();
            if (string.IsNullOrWhiteSpace(text))
            {
                dataObj = new JsonObject();
            }
            else
            {
                var node = JsonNode.Parse(text);
                if (node is not JsonObject obj)
                {
                    WebView.NavigateToString(BuildErrorHtml("参数JSON必须是对象（JSON Object）"));
                    TbStatus.Text = "参数JSON格式错误";
                    return;
                }
                dataObj = obj;
            }

            var html = NativePrintRenderService.RenderToHtml(_templateJson, dataObj);
            WebView.NavigateToString(html);
            TbStatus.Text = string.Empty;
        }
        catch (Exception ex)
        {
            WebView.NavigateToString(BuildErrorHtml(ex.Message));
            TbStatus.Text = $"渲染失败：{ex.Message}";
        }
        await Task.CompletedTask;
    }

    /// <summary>
    /// 根据模板绑定字段生成参数 JSON（便于用户直接编辑并预览）。
    /// 与 web 端 nativeMockData.ts 保持一致：识别 mergeColumnKeys 让同组相邻行字段值相同，
    /// 以便在预览中触发 rowSpan 合并显示。
    /// </summary>
    private static string BuildMockParamJson(string templateJson)
    {
        if (string.IsNullOrWhiteSpace(templateJson) || templateJson == "{}")
            return "{}";

        try
        {
            var root = JsonNode.Parse(templateJson);
            var obj = new JsonObject();
            var elements = root?["elements"]?.AsArray() ?? new JsonArray();
            var fields = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
            var rng = new Random();

            foreach (var el in elements.OfType<JsonObject>())
            {
                var type = (el["type"]?.ToString() ?? string.Empty).Trim();
                if (type is "table" or "detailTable")
                {
                    var source = (el["source"]?.ToString() ?? "mainTable").Trim();
                    if (!obj.ContainsKey(source))
                    {
                        var columns = el["columns"]?.AsArray() ?? new JsonArray();
                        var colList = columns.OfType<JsonObject>().ToList();

                        // 解析合并字段顺序：根据 mergeColumnKeys 按 column.key 映射到 bindField
                        var mergeKeys = (el["mergeColumnKeys"]?.AsArray() ?? new JsonArray())
                            .Select(n => n?.ToString() ?? string.Empty)
                            .Where(s => !string.IsNullOrEmpty(s))
                            .ToList();
                        var strictGrouping = !string.Equals(
                            el["strictGrouping"]?.ToString() ?? "true", "false",
                            StringComparison.OrdinalIgnoreCase);

                        var mergeFieldOrder = mergeKeys
                            .Select(k => colList.FirstOrDefault(c => string.Equals(c["key"]?.ToString() ?? string.Empty, k, StringComparison.Ordinal)))
                            .Where(c => c != null)
                            .Select(c => (c!["bindField"]?.ToString() ?? c!["field"]?.ToString() ?? string.Empty).Trim())
                            .Where(s => !string.IsNullOrEmpty(s))
                            .ToList();

                        var rows = new JsonArray();
                        JsonObject? prevRow = null;
                        for (var i = 0; i < 8; i++)
                        {
                            var row = new JsonObject();
                            foreach (var col in colList)
                            {
                                var field = (col["bindField"]?.ToString() ?? col["field"]?.ToString() ?? string.Empty).Trim();
                                if (string.IsNullOrWhiteSpace(field)) continue;
                                var contentType = (col["contentType"]?.ToString() ?? "text").Trim().ToLowerInvariant();
                                fields.Add(field);

                                var mergeIndex = mergeFieldOrder.IndexOf(field);
                                var enableMerge = mergeIndex >= 0;

                                if (enableMerge)
                                {
                                    // 父级合并字段在 strictGrouping 下必须与前一行一致，才允许沿用前一行值
                                    var canFollowPrev = !strictGrouping || mergeIndex == 0 || (prevRow != null &&
                                        mergeFieldOrder.Take(mergeIndex).All(parent =>
                                            (prevRow[parent]?.ToString() ?? string.Empty) == (row[parent]?.ToString() ?? string.Empty)));

                                    if (i > 0 && prevRow != null && canFollowPrev && rng.NextDouble() < 0.5)
                                    {
                                        // 沿用前一行此字段值，从而触发合并
                                        var prevVal = prevRow[field];
                                        row[field] = prevVal != null ? JsonNode.Parse(prevVal.ToJsonString()) : (JsonNode?)$"{field}_合并组1";
                                    }
                                    else
                                    {
                                        // 新合并组：随机 0-3 表示组编号
                                        row[field] = $"{field}_合并组{rng.Next(1, 5)}";
                                    }
                                    continue;
                                }

                                row[field] = contentType switch
                                {
                                    "number" => (i + 1) * 123.45,
                                    "amount" => (i + 1) * 24567.89,
                                    "qrcode" => $"QR_{field}_{i + 1}",
                                    "barcode" => $"BAR_{field}_{i + 1}",
                                    "image" => $"https://picsum.photos/seed/{Uri.EscapeDataString(field + "_" + (i + 1))}/260/120",
                                    _ => $"{field}_示例值_{i + 1}"
                                };
                            }
                            rows.Add(row);
                            prevRow = row;
                        }
                        obj[source] = rows;
                    }
                }

                var bind = (el["bindField"]?.ToString() ?? string.Empty).Trim();
                if (!string.IsNullOrWhiteSpace(bind))
                    fields.Add(bind);

                // 提取 text 中的 {{field}} 占位符（支持内嵌）
                var text = el["text"]?.ToString() ?? string.Empty;
                foreach (Match m in Regex.Matches(text, @"\{\{\s*([\w\.]+)\s*\}\}"))
                {
                    var key = m.Groups[1].Value.Trim();
                    if (!string.IsNullOrWhiteSpace(key))
                        fields.Add(key);
                }

                CollectBindFields(el["cells"], fields);
            }

            foreach (var f in fields.OrderBy(x => x, StringComparer.OrdinalIgnoreCase))
            {
                if (f.Equals("pageNo", StringComparison.OrdinalIgnoreCase) || f.Equals("totalPages", StringComparison.OrdinalIgnoreCase))
                    continue;
                if (!obj.ContainsKey(f))
                    obj[f] = $"{f}_示例值";
            }

            return obj.ToJsonString(new JsonSerializerOptions { WriteIndented = true });
        }
        catch
        {
            return "{}";
        }
    }

    private static void CollectBindFields(JsonNode? node, ISet<string> fields)
    {
        if (node == null) return;
        if (node is JsonObject o)
        {
            if (o.TryGetPropertyValue("bindField", out var bindNode))
            {
                var bind = bindNode?.ToString()?.Trim();
                if (!string.IsNullOrWhiteSpace(bind))
                    fields.Add(bind);
            }
            foreach (var kv in o)
                CollectBindFields(kv.Value, fields);
            return;
        }
        if (node is JsonArray arr)
        {
            foreach (var it in arr)
                CollectBindFields(it, fields);
        }
    }

    private static string BuildErrorHtml(string message)
    {
        var esc = message.Replace("&", "&amp;").Replace("<", "&lt;").Replace(">", "&gt;");
        return "<html><head><meta charset=\"utf-8\"/><style>"
             + "body{margin:0;background:#525659;display:flex;align-items:center;"
             + "justify-content:center;height:100vh;font-family:'Microsoft YaHei',Arial,sans-serif;}"
             + ".card{background:#fff;border-radius:8px;padding:32px 48px;text-align:center;"
             + "box-shadow:0 6px 24px rgba(0,0,0,.4);max-width:560px;}"
             + "</style></head><body><div class=\"card\">"
             + "<div style=\"font-size:40px;margin-bottom:12px\">⚠️</div>"
             + "<div style=\"font-size:13px;color:#e74c3c;word-break:break-all;\">渲染失败：" + esc + "</div>"
             + "</div></body></html>";
    }

    private async void RenderByParamJson_Click(object sender, RoutedEventArgs e)
    {
        await RenderCurrentParamJsonAsync();
    }

    private async void GenerateMockJson_Click(object sender, RoutedEventArgs e)
    {
        TbParamJson.Text = BuildMockParamJson(_templateJson);
        await RenderCurrentParamJsonAsync();
    }

    private void CloseButton_Click(object sender, RoutedEventArgs e) => Close();
}