using System.Text.Json;
using line_gestao_api.Data;
using line_gestao_api.Dtos;
using line_gestao_api.Services;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using System.Globalization;

namespace line_gestao_api.Controllers;

[ApiController]
[Route("api/historico")]
[Authorize(Roles = "admin")]
public class HistoricoController : ControllerBase
{
    private readonly AppDbContext _db;

    public HistoricoController(AppDbContext db)
    {
        _db = db;
    }

    [HttpGet]
    public async Task<ActionResult<PagedResult<AuditLogDto>>> GetAll(
        [FromQuery] string? pageName,
        [FromQuery] string? action,
        [FromQuery] string? entity,
        [FromQuery] Guid? userId,
        [FromQuery] string? search,
        [FromQuery] DateTime? dateFrom,
        [FromQuery] DateTime? dateTo,
        [FromQuery] int page = 1,
        [FromQuery] int pageSize = 20)
    {
        page = page < 1 ? 1 : page;
        pageSize = pageSize < 1 ? 20 : pageSize;

        var q = _db.AuditLogs
            .AsNoTracking()
            .Where(x =>
                !EF.Functions.ILike(x.RequestPath ?? "", "%import-excel%") ||
                x.Page == AuditLogBuilder.SpreadsheetImportPageName);

        if (!string.IsNullOrWhiteSpace(pageName))
        {
            var p = pageName.Trim();
            q = q.Where(x => EF.Functions.ILike(x.Page, $"%{p}%"));
        }

        if (!string.IsNullOrWhiteSpace(action))
        {
            var a = action.Trim().ToUpperInvariant();
            q = q.Where(x => x.Action == a);
        }

        if (!string.IsNullOrWhiteSpace(entity))
        {
            var e = entity.Trim();
            q = q.Where(x => EF.Functions.ILike(x.EntityName, $"%{e}%"));
        }

        if (userId.HasValue)
        {
            q = q.Where(x => x.UserId == userId.Value);
        }

        if (!string.IsNullOrWhiteSpace(search))
        {
            var s = search.Trim();
            var hasGuidSearch = Guid.TryParse(s, out var searchGuid);
            var hasDateSearch = TryParseSearchDateUtcStart(s, out var searchDateStartUtc);
            var searchDateEndUtc = hasDateSearch ? searchDateStartUtc.AddDays(1) : DateTime.MinValue;
            q = q.Where(x =>
                EF.Functions.ILike(x.UserName ?? "", $"%{s}%") ||
                EF.Functions.ILike(x.UserEmail ?? "", $"%{s}%") ||
                EF.Functions.ILike(x.Action ?? "", $"%{s}%") ||
                EF.Functions.ILike(x.EntityName ?? "", $"%{s}%") ||
                EF.Functions.ILike(x.EntityLabel ?? "", $"%{s}%") ||
                EF.Functions.ILike(x.EntityId ?? "", $"%{s}%") ||
                EF.Functions.ILike(x.Page ?? "", $"%{s}%") ||
                EF.Functions.ILike(x.RequestPath ?? "", $"%{s}%") ||
                EF.Functions.ILike(x.RequestMethod ?? "", $"%{s}%") ||
                EF.Functions.ILike(x.IpAddress ?? "", $"%{s}%") ||
                // ChangesJson is stored as jsonb; applying ILIKE directly causes PostgreSQL 42883.
                (hasGuidSearch && (x.Id == searchGuid || x.UserId == searchGuid)) ||
                (hasDateSearch &&
                 x.OccurredAtUtc >= searchDateStartUtc &&
                 x.OccurredAtUtc < searchDateEndUtc));
        }

        if (dateFrom.HasValue)
        {
            var fromUtc = ToUtc(dateFrom.Value);
            q = q.Where(x => x.OccurredAtUtc >= fromUtc);
        }

        if (dateTo.HasValue)
        {
            var toUtc = ToUtc(dateTo.Value);
            if (dateTo.Value.TimeOfDay == TimeSpan.Zero)
            {
                toUtc = toUtc.Date.AddDays(1).AddTicks(-1);
            }

            q = q.Where(x => x.OccurredAtUtc <= toUtc);
        }

        var total = await q.CountAsync();

        var items = await q
            .OrderByDescending(x => x.OccurredAtUtc)
            .ThenByDescending(x => x.Id)
            .Skip((page - 1) * pageSize)
            .Take(pageSize)
            .ToListAsync();

        return Ok(new PagedResult<AuditLogDto>
        {
            Page = page,
            PageSize = pageSize,
            Total = total,
            Items = items.Select(ToDto).ToList()
        });
    }

    private static AuditLogDto ToDto(Models.AuditLog log)
    {
        return new AuditLogDto
        {
            Id = log.Id,
            OccurredAtUtc = log.OccurredAtUtc,
            Action = log.Action,
            Page = log.Page,
            EntityName = log.EntityName,
            EntityId = log.EntityId,
            EntityLabel = log.EntityLabel,
            UserId = log.UserId,
            UserName = log.UserName,
            UserEmail = log.UserEmail,
            RequestPath = log.RequestPath,
            RequestMethod = log.RequestMethod,
            IpAddress = log.IpAddress,
            Changes = ParseChanges(log.ChangesJson)
        };
    }

    private static List<AuditFieldChangeDto> ParseChanges(string? json)
    {
        if (string.IsNullOrWhiteSpace(json))
        {
            return new List<AuditFieldChangeDto>();
        }

        try
        {
            return JsonSerializer.Deserialize<List<AuditFieldChangeDto>>(json) ?? new List<AuditFieldChangeDto>();
        }
        catch
        {
            return new List<AuditFieldChangeDto>();
        }
    }

    private static DateTime ToUtc(DateTime value)
    {
        if (value.Kind == DateTimeKind.Utc)
            return value;
        if (value.Kind == DateTimeKind.Local)
            return value.ToUniversalTime();

        return DateTime.SpecifyKind(value, DateTimeKind.Utc);
    }

    private static bool TryParseSearchDateUtcStart(string value, out DateTime utcStart)
    {
        utcStart = default;
        if (string.IsNullOrWhiteSpace(value)) return false;

        var s = value.Trim();
        DateTime parsed;

        if (DateTime.TryParse(s, new CultureInfo("pt-BR"), DateTimeStyles.None, out parsed) ||
            DateTime.TryParse(s, CultureInfo.InvariantCulture, DateTimeStyles.None, out parsed))
        {
            utcStart = DateTime.SpecifyKind(parsed.Date, DateTimeKind.Utc);
            return true;
        }

        return false;
    }
}