using System.Text.RegularExpressions;
using Oms.Application.Services.Orders.Templates;

namespace Oms.Application.Services.Orders.Templates;

/// <summary>
/// 客户 Excel 表头与标准字段智能匹配。
/// </summary>
public static class OrderTemplateHeaderMatcher
{
    private static readonly Regex NoisePattern = new(@"[\s\*\(\)（）\[\]【】:：,，.。/\\\-_]+", RegexOptions.Compiled);

    private static readonly Dictionary<string, string> Aliases = new(StringComparer.OrdinalIgnoreCase)
    {
        ["客户单号"] = "clientNo",
        ["客户订单号"] = "clientNo",
        ["外部单号"] = "clientNo",
        ["运输方式"] = "productCode",
        ["产品代码"] = "productCode",
        ["产品编码"] = "productCode",
        ["货物属性"] = "cargoAttribute",
        ["出口报关方式"] = "exportCustomsMode",
        ["出口报关"] = "exportCustomsMode",
        ["出口资质备案Id"] = "exportQualificationId",
        ["出口资质备案"] = "exportQualificationId",
        ["资质备案Id"] = "exportQualificationId",
        ["仓库"] = "warehouseId",
        ["仓库ID"] = "warehouseId",
        ["长cm"] = "length",
        ["长"] = "length",
        ["宽cm"] = "width",
        ["宽"] = "width",
        ["高cm"] = "height",
        ["高"] = "height",
        ["实重kg"] = "actualWeight",
        ["实重"] = "actualWeight",
        ["申报币种"] = "declaredCurrency",
        ["申报金额"] = "declaredSum",
        ["申报总金额"] = "declaredSum",
        ["包裹数量"] = "quantity",
        ["收件人名称"] = "receiver.recipientsName",
        ["收件姓名"] = "receiver.recipientsName",
        ["收件人手机"] = "receiver.phone",
        ["收件国家代码"] = "receiver.countryCode",
        ["收件国家"] = "receiver.countryCode",
        ["收件地址1"] = "receiver.streetAddress1",
        ["收件邮编"] = "receiver.zipCode",
        ["发件人姓名"] = "sender.senderName",
        ["申报品名英"] = "items[0].enName",
        ["品名英"] = "items[0].enName",
        ["申报品名中"] = "items[0].cnName",
        ["单价"] = "items[0].unitPrice",
        ["单价元"] = "items[0].unitPrice",
        ["单重"] = "items[0].unitWeight",
        ["单重kg"] = "items[0].unitWeight",
        ["申报数量"] = "items[0].quantity",
        ["总金额"] = "items[0].amount",
        ["总金额元"] = "items[0].amount",
        ["总重量"] = "items[0].weight",
        ["总重量kg"] = "items[0].weight",
    };

    public static string? MatchStandardFieldKey(string? sourceHeader, string? templateKey)
    {
        var normalized = Normalize(sourceHeader);
        if (string.IsNullOrWhiteSpace(normalized))
        {
            return null;
        }

        if (Aliases.TryGetValue(normalized, out var aliasKey))
        {
            return aliasKey;
        }

        var fields = OrderTemplateFieldRegistry.GetFields(templateKey);
        var byLabel = fields.FirstOrDefault(f => Normalize(f.Label) == normalized);
        if (byLabel != null)
        {
            return byLabel.FieldKey;
        }

        return fields.FirstOrDefault(f =>
            normalized.Contains(Normalize(f.Label), StringComparison.OrdinalIgnoreCase) ||
            Normalize(f.Label).Contains(normalized, StringComparison.OrdinalIgnoreCase))?.FieldKey;
    }

    public static OrderTemplateColumnMappingDocument BuildSuggestedMapping(
        string standardTemplateKey,
        IReadOnlyList<string> sourceHeaders)
    {
        var fields = OrderTemplateFieldRegistry.GetFields(standardTemplateKey);
        var usedColumns = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        var mappings = new List<OrderTemplateColumnMappingItem>();

        foreach (var field in fields)
        {
            var matched = sourceHeaders.FirstOrDefault(h =>
            {
                var key = MatchStandardFieldKey(h, standardTemplateKey);
                return string.Equals(key, field.FieldKey, StringComparison.OrdinalIgnoreCase);
            });
            if (!string.IsNullOrWhiteSpace(matched) && usedColumns.Add(matched))
            {
                mappings.Add(new OrderTemplateColumnMappingItem
                {
                    StandardFieldKey = field.FieldKey,
                    SourceColumn = matched,
                    Required = field.Required
                });
            }
        }

        var mappedColumns = mappings.Select(x => x.SourceColumn).ToHashSet(StringComparer.OrdinalIgnoreCase);
        return new OrderTemplateColumnMappingDocument
        {
            StandardTemplateKey = standardTemplateKey,
            HeaderRowIndex = 1,
            DataStartRowIndex = 2,
            Mappings = mappings,
            UnmappedSourceColumns = sourceHeaders.Where(h => !mappedColumns.Contains(h)).ToList()
        };
    }

    public static List<string> ReadHeaderRow(Stream stream)
    {
        stream.Position = 0;
        var firstRow = MiniExcelLibs.MiniExcel.Query(stream, useHeaderRow: false)
            .Take(1)
            .Cast<IDictionary<string, object>>()
            .FirstOrDefault();

        if (firstRow == null)
        {
            return [];
        }

        return firstRow.Values
            .Select(v => v?.ToString()?.Trim())
            .Where(v => !string.IsNullOrWhiteSpace(v))
            .Select(v => v!)
            .Distinct(StringComparer.OrdinalIgnoreCase)
            .ToList();
    }

    public static string NormalizeHeader(string? text)
    {
        if (string.IsNullOrWhiteSpace(text))
        {
            return string.Empty;
        }

        return NoisePattern.Replace(text.Trim(), string.Empty);
    }

    private static string Normalize(string? text) => NormalizeHeader(text);
}