using PostFundManagement.Application.Shared;
using PostFundManagement.Domain;
using PostFundManagement.Domain.Abstractions;
using PostFundManagement.Domain.Extensions;
using PostFundManagement.Domain.Models;
using PostFundManagement.Infrastructure.Database;

namespace PostFundManagement.Application.Services.Execution;

public sealed class ExecutionService(IDbContextFactory<ApplicationDbContext> contextFactory, HashService hashService) : IService
{
    public async Task<Result<Risk[]>> GetRisksAsync(Pagination pagination, CancellationToken cancellationToken = default)
    {
        try
        {
            using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            var risks = await context.Risks.AsNoTracking()
                .OrderByDescending(r => r.CreatedAt)
                .Skip((pagination.Page - 1) * pagination.PageSize)
                .Take(pagination.PageSize)
                .ToListAsync(cancellationToken);

            return Result.Ok(risks?.Select(i => i.Map()).ToArray() ?? []);
        }
        catch (Exception ex)
        {
            return Result.Fail(new Error(ex.Message).CausedBy(ex));
        }
    }

    public async ValueTask<Result<Risk[]>> GetProjectRisksAsync(string projectIdHash, CancellationToken cancellationToken = default)
    {
        try
        {
            var decodeResult = hashService.DecodeLongIdHash(projectIdHash);

            if (decodeResult.IsFailed)
                return Result.Fail(decodeResult.Errors);

            using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            var risks = await context.Risks.AsNoTracking()
                .Where(r => r.ProjectId == decodeResult.Value)
                .OrderByDescending(r => r.CreatedAt)
                .ToListAsync(cancellationToken);

            return Result.Ok(risks?.Select(i => i.Map()).ToArray() ?? []);
        }
        catch (Exception ex)
        {
            return Result.Fail(new Error(ex.Message).CausedBy(ex));
        }
    }

    public async ValueTask<Result<Disbursement[]>> GetDisbursementsAsync(Pagination pagination, CancellationToken cancellationToken = default)
    {
        try
        {
            using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            var disbursements = await context.Disbursements.AsNoTracking()
                .OrderByDescending(d => d.CreatedAt)
                .Skip((pagination.Page - 1) * pagination.PageSize)
                .Take(pagination.PageSize)
                .ToListAsync(cancellationToken);

            return Result.Ok(disbursements?.Select(i => i.Map()).ToArray() ?? []);
        }
        catch (Exception ex)
        {
            return Result.Fail(new Error(ex.Message).CausedBy(ex));
        }
    }

    public async ValueTask<Result> CreateRiskAsync(CreateRiskRequest request, Guid userId, CancellationToken cancellationToken = default)
    {
        try
        {
            using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            if (!await context.Projects.AnyAsync(p => p.Id == request.ProjectId, cancellationToken))
                return Result.Fail($"Project with ID {request.ProjectId} does not exist.");

            context.Risks.Add(new Domain.Entities.Risk
            {
                ProjectId = request.ProjectId,
                Likelihood = request.Likelihood,
                Impact = request.Impact,
                Name = request.Name,
                Description = request.Description,
                CreatedBy = userId,
                CreatedAt = DateTime.UtcNow
            });

            return await context.SaveChangesAsync(cancellationToken) > 0
                ? Result.Ok()
                : Result.Fail("Failed to create project risk");
        }
        catch (Exception ex)
        {
            return Result.Fail(new Error(ex.Message).CausedBy(ex));
        }
    }

    public async ValueTask<Result> CreateDisbursementAsync(CreateDisbursementRequest request, Guid userId, CancellationToken cancellationToken = default)
    {
        try
        {
            using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            if (!await context.Projects.AnyAsync(p => p.Id == request.ProjectId, cancellationToken))
                return Result.Fail($"Project with ID {request.ProjectId} does not exist.");

            context.Disbursements.Add(new Domain.Entities.Disbursement
            {
                ProjectId = request.ProjectId,
                MilestoneId = request.MilestoneId,
                Amount = request.Amount,
                Status = ApprovalStatus.Pending,
                CreatedBy = userId,
                CreatedAt = DateTime.UtcNow
            });

            return await context.SaveChangesAsync(cancellationToken) > 0
                ? Result.Ok()
                : Result.Fail("Failed to create disbursement");
        }
        catch (Exception ex)
        {
            return Result.Fail(new Error(ex.Message).CausedBy(ex));
        }
    }

    public async ValueTask<Result> ApproveDisbursementAsync(string disbursementIdHash, Guid userId, CancellationToken cancellationToken = default)
    {
		try
		{
            var decodeResult = hashService.DecodeLongIdHash(disbursementIdHash);

            if (decodeResult.IsFailed)
                return Result.Fail("Invalid disbursementId");

            using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            var totalSaved = await context.Disbursements.Where(d => d.Id == decodeResult.Value)
                .ExecuteUpdateAsync(f =>
                    f.SetProperty(f => f.Status, ApprovalStatus.Approved)
                    .SetProperty(f => f.UpdatedBy, userId)
                    .SetProperty(f => f.UpdatedAt, DateTime.UtcNow), cancellationToken);

            return totalSaved > 0
                ? Result.Ok()
                : Result.Fail("Failed to approve payment");
        }
		catch (Exception ex)
		{
            return Result.Fail(new Error(ex.Message).CausedBy(ex));
        }
    }
}