using Fake.Application;
using Microsoft.AspNetCore.Mvc;
using Oms.Application.Dtos.Channels;
using Oms.Application.Dtos.Shared;
using Oms.Application.Labeling;
using Oms.Application.Shared;
using Oms.Domain.ChannelsAggregate.Consts;
using Oms.Domain.ChannelsAggregate.Entities;
using Oms.Domain.ChannelsAggregate.Repositories;

namespace Oms.Application.Services.Channels;

/// <summary>
/// 面单模板 API 服务。
/// </summary>
[ApiExplorerSettings(GroupName = "OMS-Channel")]
public class LabelTemplateService : ApplicationService
{
    private ILabelTemplateRepository LabelTemplateRepository => LazyServiceProvider.GetRequiredService<ILabelTemplateRepository>();
    private LabelPdfGenerationService LabelPdfGenerationService =>
        LazyServiceProvider.GetRequiredService<LabelPdfGenerationService>();

    /// <summary>
    /// 标签模板列表（不含 JSON，供浏览/下拉）。
    /// </summary>
    [HttpGet("/channel/label-template/list")]
    public async Task<OmsItemsResult<LabelTemplateListItemOutput>> GetListAsync(
        [FromQuery] string? keyword = null,
        [FromQuery] string? templateType = null)
    {
        var keywordValue = keyword?.Trim();
        var typeValue = templateType?.Trim();
        var hasKeyword = !string.IsNullOrEmpty(keywordValue);
        var hasType = !string.IsNullOrEmpty(typeValue);

        var entities = await LabelTemplateRepository.GetListAsync(x =>
            (!hasKeyword || x.Name.Contains(keywordValue!)) &&
            (!hasType || x.TemplateType == typeValue));

        var items = entities
            .OrderByDescending(x => x.UpdateTime)
            .ThenByDescending(x => x.Id)
            .Select(x => new LabelTemplateListItemOutput
            {
                Id = x.Id,
                Name = x.Name,
                TemplateType = x.TemplateType,
                CreateTime = x.CreateTime,
                UpdateTime = OmsDocHelper.NullIfDefault(x.UpdateTime)
            })
            .ToList();

        return new OmsItemsResult<LabelTemplateListItemOutput> { Items = items };
    }

    /// <summary>
    /// 标签模板详情（含 TemplateJson，编辑用）。
    /// </summary>
    [HttpGet("/channel/label-template/{id:int}")]
    public async Task<LabelTemplateSaveOutput> GetAsync(int id)
    {
        var entity = await GetEntityOrThrowAsync(id);
        return MapOutput(entity);
    }

    /// <summary>
    /// 设计器字段字典（可拖字段分组）。
    /// </summary>
    [HttpGet("/channel/label-template/field-dictionary")]
    public Task<OmsItemsResult<LabelFieldGroup>> GetFieldDictionaryAsync()
    {
        return Task.FromResult(new OmsItemsResult<LabelFieldGroup>
        {
            Items = LabelFieldDictionary.GetGroups().ToList()
        });
    }

    /// <summary>
    /// 预览 PDF（同一套 ILabelPdfRenderer）。
    /// </summary>
    [HttpPost("/channel/label-template/preview-pdf")]
    public async Task<FileContentResult> PreviewPdfAsync([FromBody] LabelTemplatePreviewInput input)
    {
        string? templateJson = null;
        string? templateType = null;
        if (input.TemplateId is > 0)
        {
            var entity = await GetEntityOrThrowAsync(input.TemplateId.Value);
            templateJson = entity.TemplateJson;
            templateType = entity.TemplateType;
        }
        else
        {
            templateJson = OmsDocHelper.SerializeJson(input.TemplateJson);
        }

        if (string.IsNullOrWhiteSpace(templateJson))
        {
            throw new BusinessException("模板 JSON 为空");
        }

        IReadOnlyDictionary<string, object?>? printData = null;
        if (input.PrintData is { Count: > 0 })
        {
            printData = input.PrintData.ToDictionary(
                x => x.Key,
                x => x.Value,
                StringComparer.OrdinalIgnoreCase);
        }
        else if (string.Equals(templateType, LabelTemplateTypeCodes.Box, StringComparison.OrdinalIgnoreCase))
        {
            printData = InboundBoxLabelPrintDataBuilder.BuildMock();
        }
        else if (string.Equals(templateType, LabelTemplateTypeCodes.Sku, StringComparison.OrdinalIgnoreCase))
        {
            printData = SkuLabelPrintDataBuilder.BuildMock();
        }

        var bytes = await LabelPdfGenerationService.PreviewAsync(templateJson, printData);
        return new FileContentResult(bytes, "application/pdf")
        {
            FileDownloadName = $"label-preview-{DateTime.Now:yyyyMMddHHmmss}.pdf"
        };
    }

    /// <summary>
    /// 保存标签模板。
    /// </summary>
    [HttpPost("/channel/label-template/save")]
    public async Task<LabelTemplateSaveOutput> SaveAsync(LabelTemplateSaveInput input)
    {
        LabelTemplate entity;
        if (input.Id > 0)
        {
            entity = await GetEntityOrThrowAsync(input.Id);
            await ValidateUniqueNameAsync(input.Name, input.TemplateType, entity.Id);
            entity.Name = input.Name;
            entity.TemplateType = input.TemplateType;
            entity.TemplateJson = OmsDocHelper.SerializeJson(input.TemplateJson);
            await LabelTemplateRepository.UpdateAsync(entity);
        }
        else
        {
            await ValidateUniqueNameAsync(input.Name, input.TemplateType, null);
            entity = new LabelTemplate
            {
                Name = input.Name,
                TemplateType = input.TemplateType,
                TemplateJson = OmsDocHelper.SerializeJson(input.TemplateJson)
            };
            entity = await LabelTemplateRepository.InsertAsync(entity);
        }

        return MapOutput(entity);
    }

    /// <summary>
    /// 删除标签模板。
    /// </summary>
    [HttpPost("/channel/label-template/delete")]
    public async Task DeleteAsync(IdInput input)
    {
        var entity = await GetEntityOrThrowAsync(input.Id);
        await LabelTemplateRepository.DeleteAsync(entity);
    }

    private async Task ValidateUniqueNameAsync(string name, string? templateType, int? id)
    {
        var existed = await LabelTemplateRepository.GetByNameAndTypeAsync(name, templateType);
        if (existed != null && existed.Id != id)
        {
            throw new BusinessException("标签模板名称已存在");
        }
    }

    private async Task<LabelTemplate> GetEntityOrThrowAsync(int id)
    {
        var entity = await LabelTemplateRepository.FirstOrDefaultAsync(x => x.Id == id);
        if (entity == null)
        {
            throw new BusinessException("标签模板不存在");
        }

        return entity;
    }

    private static LabelTemplateSaveOutput MapOutput(LabelTemplate entity)
    {
        return new LabelTemplateSaveOutput
        {
            Id = entity.Id,
            Name = entity.Name,
            TemplateType = entity.TemplateType,
            TemplateJson = OmsDocHelper.DeserializeJsonObject(entity.TemplateJson),
            CreateTime = entity.CreateTime,
            UpdateTime = OmsDocHelper.NullIfDefault(entity.UpdateTime)
        };
    }
}