using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.Json;
using System.Text.RegularExpressions;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Authorization;
using Sozsoft.Mcp.Dtos;
using Sozsoft.Mcp.Services;
using Sozsoft.Platform;
using Sozsoft.Platform.Entities;
using Sozsoft.Platform.Enums;
using Sozsoft.Platform.ListForms.Select;
using Volo.Abp;
using Volo.Abp.Domain.Repositories;

namespace Sozsoft.Mcp;

/// <summary>
/// Rapor kategorisi ve <c>DynamicReport</c> sablonu uretimi. Okuma depodan, yazma ekranlarin
/// C/U/D sozlesmesinden (<see cref="IListFormDataAppService"/>) gecer; boylece ekran yetkisi,
/// kiraci filtresi ve seed senkronizasyonu ekrandaki kayitla ayni kalir.
/// </summary>
[Authorize(PlatformConsts.AppCodes.DeveloperKits.McpServers.Invoke)]
public partial class McpReportAppService(
    IMcpServerConfigProvider serverConfigProvider,
    IListFormDataAppService listFormDataAppService,
    IMcpListFormAccessFilter accessFilter,
    IRepository<ReportCategory, Guid> categoryRepository,
    IRepository<ReportTemplate, Guid> templateRepository,
    IRepository<ListForm, Guid> listFormRepository,
    IRepository<ListFormField, Guid> listFormFieldRepository,
    IMcpDevRequestTimesheetRecorder timesheetRecorder)
    : McpAppService(serverConfigProvider), IMcpReportAppService
{
    private const string CategoriesListFormCode = PlatformConsts.AppCodes.Reports.Categories;
    private const string TemplatesListFormCode = PlatformConsts.AppCodes.Reports.ReportTemplates;
    private const string ActiveStatus = "active";
    private const string DefaultButtonText = "Sas.Platform.View";

    [GeneratedRegex(@"\{\{\s*([A-Za-z_][A-Za-z0-9_]*)\s*\}\}")]
    private static partial Regex PlaceholderRegex();

    public async Task<McpOutcome<McpReportCatalogDto>> GetReportTemplatesAsync(string? search)
    {
        if (await EnsureCanReadAsync(McpToolNames.ListReportTemplates) is { } problem)
        {
            return problem;
        }

        var categories = await categoryRepository.GetListAsync();
        var categoryNames = categories.ToDictionary(x => x.Id, x => x.Name);
        var templates = (await templateRepository.GetListAsync())
            .Where(x => string.IsNullOrWhiteSpace(search) ||
                x.Name.Contains(search, StringComparison.OrdinalIgnoreCase) ||
                (x.Description?.Contains(search, StringComparison.OrdinalIgnoreCase) ?? false))
            .OrderBy(x => x.Name)
            .Select(x => new McpReportTemplateSummaryDto
            {
                Id = x.Id,
                Name = x.Name,
                Description = x.Description,
                Category = categoryNames.GetValueOrDefault(x.CategoryId, string.Empty),
                Status = x.Status
            })
            .ToList();

        return new McpReportCatalogDto
        {
            Categories = [.. categories.OrderBy(x => x.Name).Select(ToDto)],
            Templates = templates
        };
    }

    public async Task<McpOutcome<McpReportTemplateDto>> GetReportTemplateAsync(string template)
    {
        if (await EnsureCanReadAsync(McpToolNames.GetReportTemplate) is { } problem)
        {
            return problem;
        }

        var entity = await FindTemplateAsync(template);
        if (entity is null)
        {
            return Problem(McpErrorCodes.ReportTemplateNotFound, template);
        }

        return await ToDtoAsync(entity, null, null);
    }

    public async Task<McpOutcome<McpReportCategoryDto>> SaveReportCategoryAsync(McpReportCategorySaveRequestDto input)
    {
        Check.NotNull(input, nameof(input));
        const string toolName = McpToolNames.SaveReportCategory;

        if (await EnsureToolAllowedAsync(toolName) is { Problem: { } problem })
        {
            return problem;
        }

        if (string.IsNullOrWhiteSpace(input.Name))
        {
            return Problem(McpErrorCodes.ReportNameRequired);
        }

        var name = input.Name.Trim();
        var existing = await categoryRepository.FirstOrDefaultAsync(x => x.Name == name);
        var values = new Dictionary<string, object?>
        {
            ["Name"] = name,
            ["Description"] = input.Description ?? existing?.Description,
            ["Icon"] = input.Icon ?? existing?.Icon
        };

        var saved = existing is null
            ? await InsertAsync(toolName, CategoriesListFormCode, values)
            : await UpdateAsync(toolName, CategoriesListFormCode, existing.Id, values);
        if (!saved.TryGetValue(out var id, out var rejected))
        {
            return rejected;
        }

        await timesheetRecorder.RecordAsync(McpTimesheetTexts.SaveReportCategory, name);

        var category = await categoryRepository.FirstOrDefaultAsync(x => x.Id == id);
        return category is null ? new McpReportCategoryDto { Id = id, Name = name } : ToDto(category);
    }

    public async Task<McpOutcome<McpReportTemplateDto>> SaveReportTemplateAsync(McpReportTemplateSaveRequestDto input)
    {
        Check.NotNull(input, nameof(input));
        const string toolName = McpToolNames.SaveReportTemplate;

        if (await EnsureToolAllowedAsync(toolName) is { Problem: { } problem })
        {
            return problem;
        }

        if (string.IsNullOrWhiteSpace(input.Name))
        {
            return Problem(McpErrorCodes.ReportNameRequired);
        }

        var name = input.Name.Trim();
        var existing = await templateRepository.FirstOrDefaultAsync(x => x.Name == name);
        var htmlContent = string.IsNullOrWhiteSpace(input.HtmlContent) ? existing?.HtmlContent : input.HtmlContent;
        if (string.IsNullOrWhiteSpace(htmlContent))
        {
            return Problem(McpErrorCodes.ReportHtmlRequired);
        }

        var categoryId = existing?.CategoryId;
        if (!string.IsNullOrWhiteSpace(input.Category))
        {
            categoryId = (await FindCategoryAsync(input.Category))?.Id;
            if (categoryId is null)
            {
                return Problem(McpErrorCodes.ReportCategoryNotFound, input.Category);
            }
        }

        if (categoryId is null)
        {
            return Problem(McpErrorCodes.ReportCategoryRequired);
        }

        if (!(await FindListFormAsync(input.ListFormCode)).TryGetValue(out var listForm, out var notFound))
        {
            return notFound;
        }

        if (listForm is not null && await CheckPlaceholdersExistAsync(listForm.ListFormCode, htmlContent) is { } unknown)
        {
            return unknown;
        }

        var values = new Dictionary<string, object?>
        {
            ["Name"] = name,
            ["Description"] = input.Description ?? existing?.Description,
            ["HtmlContent"] = htmlContent,
            ["CategoryId"] = categoryId,
            ["Status"] = input.Status ?? existing?.Status ?? ActiveStatus
        };

        var saved = existing is null
            ? await InsertAsync(toolName, TemplatesListFormCode, values)
            : await UpdateAsync(toolName, TemplatesListFormCode, existing.Id, values);
        if (!saved.TryGetValue(out var id, out var rejected))
        {
            return rejected;
        }

        await timesheetRecorder.RecordAsync(McpTimesheetTexts.SaveReportTemplate, name);

        var template = await templateRepository.FirstOrDefaultAsync(x => x.Id == id);
        if (template is null)
        {
            return Problem(McpErrorCodes.ReportTemplateNotFound, name);
        }

        return await ToDtoAsync(template, listForm, input.ButtonText);
    }

    public async Task<McpProblem?> DeleteReportTemplateAsync(string template)
    {
        const string toolName = McpToolNames.DeleteReportTemplate;

        if (await EnsureToolAllowedAsync(toolName) is { Problem: { } problem })
        {
            return problem;
        }

        var entity = await FindTemplateAsync(template);
        if (entity is null)
        {
            return Problem(McpErrorCodes.ReportTemplateNotFound, template);
        }

        if (!(await BuildRequestAsync(toolName, TemplatesListFormCode, AuthorizationTypeEnum.Delete, null, entity.Id)).TryGetValue(out var request, out var denied))
        {
            return denied;
        }

        await listFormDataAppService.PostDeleteAsync(request);
        await timesheetRecorder.RecordAsync(McpTimesheetTexts.DeleteReportTemplate, entity.Name);

        return null;
    }

    /// <summary>
    /// Okuma depodan yapildigi icin ekranin okuma yetkisi burada istenir; MCP kullanicinin
    /// uygulamada goremedigi sablonu gostermez.
    /// </summary>
    private async Task<McpProblem?> EnsureCanReadAsync(string toolName)
    {
        if (await EnsureToolAllowedAsync(toolName) is { Problem: { } problem })
        {
            return problem;
        }

        var permission = await accessFilter.GetPermissionNameAsync(TemplatesListFormCode, AuthorizationTypeEnum.Read);
        return await CheckPermissionAsync(toolName, permission ?? TemplatesListFormCode);
    }

    private async Task<McpOutcome<Guid>> InsertAsync(string toolName, string listFormCode, Dictionary<string, object?> values)
    {
        if (!(await BuildRequestAsync(toolName, listFormCode, AuthorizationTypeEnum.Create, values, null)).TryGetValue(out var request, out var problem))
        {
            return problem;
        }

        var key = await listFormDataAppService.PostInsertAsync(request);

        // Insert ucu her veri kaynaginda anahtari dondurmez; bu durumda tekil ad uzerinden bulunur.
        if (Guid.TryParse(((object?)key)?.ToString(), out var id))
        {
            return id;
        }

        var name = (string)values["Name"]!;
        return listFormCode == CategoriesListFormCode
            ? (await categoryRepository.FirstAsync(x => x.Name == name)).Id
            : (await templateRepository.FirstAsync(x => x.Name == name)).Id;
    }

    private async Task<McpOutcome<Guid>> UpdateAsync(string toolName, string listFormCode, Guid id, Dictionary<string, object?> values)
    {
        if (!(await BuildRequestAsync(toolName, listFormCode, AuthorizationTypeEnum.Update, values, id)).TryGetValue(out var request, out var problem))
        {
            return problem;
        }

        await listFormDataAppService.PostUpdateAsync(request);
        return id;
    }

    /// <summary>
    /// Ekranin kendi kontrolu reddi adsiz bir hatayla bildirir; yetki burada adiyla istenir ki
    /// istemci hangi yetkinin eksik oldugunu gorsun.
    /// </summary>
    private async Task<McpOutcome<DataRequestDto>> BuildRequestAsync(
        string toolName,
        string listFormCode,
        AuthorizationTypeEnum operation,
        Dictionary<string, object?>? values,
        Guid? key)
    {
        var permission = await accessFilter.GetPermissionNameAsync(listFormCode, operation);
        if (permission is not null && await CheckPermissionAsync(toolName, permission) is { } denied)
        {
            return denied;
        }

        return new DataRequestDto
        {
            ListFormCode = listFormCode,
            Data = JsonSerializer.Serialize(values ?? []),
            Keys = key is null ? [] : [key.Value]
        };
    }

    private async Task<ReportTemplate?> FindTemplateAsync(string template)
    {
        if (string.IsNullOrWhiteSpace(template))
        {
            return null;
        }

        var value = template.Trim();
        return Guid.TryParse(value, out var id)
            ? await templateRepository.FirstOrDefaultAsync(x => x.Id == id)
            : await templateRepository.FirstOrDefaultAsync(x => x.Name == value);
    }

    private async Task<ReportCategory?> FindCategoryAsync(string category)
    {
        var value = category.Trim();
        return Guid.TryParse(value, out var id)
            ? await categoryRepository.FirstOrDefaultAsync(x => x.Id == id)
            : await categoryRepository.FirstOrDefaultAsync(x => x.Name == value);
    }

    /// <summary>Kod verilmediyse null; verilen kodun ekrani yoksa sorun.</summary>
    private async Task<McpOutcome<ListForm?>> FindListFormAsync(string? listFormCode)
    {
        if (string.IsNullOrWhiteSpace(listFormCode))
        {
            return default(ListForm);
        }

        var code = listFormCode.Trim();
        var listForm = await listFormRepository.FirstOrDefaultAsync(x => x.ListFormCode == code);

        return listForm is null ? Problem(McpErrorCodes.ReportListFormNotFound, code) : listForm;
    }

    /// <summary>
    /// Bilinmeyen yer tutucu raporda oldugu gibi basilir; sertifikada "{{AdSoyad}}" gorunmesin
    /// diye kayitta reddedilir.
    /// </summary>
    private async Task<McpProblem?> CheckPlaceholdersExistAsync(string listFormCode, string htmlContent)
    {
        var fieldNames = (await listFormFieldRepository.GetListAsync(x => x.ListFormCode == listFormCode))
            .Select(x => x.FieldName)
            .ToHashSet(StringComparer.OrdinalIgnoreCase);
        var unknown = GetPlaceholders(htmlContent).Where(x => !fieldNames.Contains(x)).ToList();

        return unknown.Count == 0
            ? null
            : Problem(McpErrorCodes.ReportPlaceholdersUnknown, listFormCode, string.Join(", ", unknown));
    }

    private static List<string> GetPlaceholders(string htmlContent)
        => [.. PlaceholderRegex().Matches(htmlContent ?? string.Empty)
            .Select(x => x.Groups[1].Value)
            .Distinct(StringComparer.OrdinalIgnoreCase)];

    private async Task<McpReportTemplateDto> ToDtoAsync(ReportTemplate entity, ListForm? listForm, string? buttonText)
    {
        var category = await categoryRepository.FirstOrDefaultAsync(x => x.Id == entity.CategoryId);
        var viewUrl = $"/admin/reports/DynamicReport/view/{entity.Id}";

        return new McpReportTemplateDto
        {
            Id = entity.Id,
            Name = entity.Name,
            Description = entity.Description,
            Category = category?.Name ?? string.Empty,
            CategoryId = entity.CategoryId,
            Status = entity.Status,
            HtmlContent = entity.HtmlContent,
            Placeholders = GetPlaceholders(entity.HtmlContent),
            ViewUrl = viewUrl,
            RowButton = listForm is null ? null : new McpReportRowButtonDto
            {
                Text = string.IsNullOrWhiteSpace(buttonText) ? DefaultButtonText : buttonText,
                Hint = string.IsNullOrWhiteSpace(buttonText) ? DefaultButtonText : buttonText,
                Url = $"{viewUrl}/{listForm.ListFormCode}?recordId=@{listForm.KeyFieldName}",
                AuthName = listForm.ListFormCode
            }
        };
    }

    private static McpReportCategoryDto ToDto(ReportCategory category) => new()
    {
        Id = category.Id,
        Name = category.Name,
        Description = category.Description,
        Icon = category.Icon
    };
}