using System.Globalization;
using System.Text.RegularExpressions;
using line_gestao_api.Data;
using line_gestao_api.Models;
using Microsoft.EntityFrameworkCore;

namespace line_gestao_api.Services;

public static class AutoFillRules
{
    private static readonly Regex FranquiaRegex = new(
        @"(?<val>\d+(?:[.,]\d+)?)\s*(?<unit>GB|MB)",
        RegexOptions.IgnoreCase | RegexOptions.Compiled);

    public sealed record PlanSuggestion(decimal? FranquiaGb, decimal? ValorPlano);

    public static async Task<PlanSuggestion?> ResolvePlanSuggestionAsync(AppDbContext db, string? planoContrato)
    {
        var plan = (planoContrato ?? string.Empty).Trim();
        if (string.IsNullOrWhiteSpace(plan)) return null;

        ResumoPlanoContratoResumo? resumoPlano = await db.ResumoPlanoContratoResumos
            .AsNoTracking()
            .Where(x => x.PlanoContrato != null && EF.Functions.ILike(x.PlanoContrato, plan))
            .OrderByDescending(x => x.UpdatedAt)
            .FirstOrDefaultAsync();

        ResumoMacrophonyPlan? macroPlan = null;
        if (resumoPlano == null)
        {
            macroPlan = await db.ResumoMacrophonyPlans
                .AsNoTracking()
                .Where(x => x.PlanoContrato != null && EF.Functions.ILike(x.PlanoContrato, plan))
                .OrderByDescending(x => x.UpdatedAt)
                .FirstOrDefaultAsync();
        }

        decimal? franquia = resumoPlano?.FranquiaGb ?? resumoPlano?.Gb;
        decimal? valor = resumoPlano?.ValorIndividualComSvas;

        if (macroPlan != null)
        {
            franquia ??= macroPlan.FranquiaGb ?? macroPlan.Gb;
            valor ??= macroPlan.ValorIndividualComSvas;
        }

        franquia ??= ParseFranquiaGbFromPlano(plan);

        return new PlanSuggestion(franquia, valor);
    }

    public static decimal? ParseFranquiaGbFromPlano(string? planoContrato)
    {
        if (string.IsNullOrWhiteSpace(planoContrato)) return null;

        var match = FranquiaRegex.Match(planoContrato);
        if (!match.Success) return null;

        var raw = match.Groups["val"].Value.Replace(",", ".");
        if (!decimal.TryParse(raw, NumberStyles.Any, CultureInfo.InvariantCulture, out var value))
        {
            return null;
        }

        var unit = match.Groups["unit"].Value.ToUpperInvariant();
        if (unit == "MB")
        {
            return Math.Round(value / 1000m, 4);
        }

        return value;
    }
}