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

namespace PostFundManagement.Application.Services.Governance;

public sealed class GovernanceService(IDbContextFactory<ApplicationDbContext> contextFactory, HashService hashService,
    ITenantContextService tenantContext) : IGovernanceService
{
    public async Task<Result<Programme[]>> GetProgrammesAsync(string portfolioIdHash, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result<Programme[]>>>)(async () =>
        {
            var decodeResult = hashService.DecodeLongIdHash(portfolioIdHash);

            if (decodeResult.IsFailed)
                return Result.Fail(IdDecodeError.Create()
                    .CausedBy(decodeResult.Errors));

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

            var programmes = await context.Programmes.AsNoTracking()
                .Where(p => p.PortfolioId == decodeResult.Value)
                .OrderByDescending(o => o.CreatedAt)
                .ToListAsync(cancellationToken);

            return Result.Ok(programmes.Select(p => p.Map()).ToArray());
        }));

    public async Task<Result<Portfolio[]>> GetPorfoliosAsync(string organisationIdHash, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result<Portfolio[]>>>)(async () =>
        {
            var decodeResult = hashService.DecodeLongIdHash(organisationIdHash);

            if (decodeResult.IsFailed)
                return Result.Fail(IdDecodeError.Create()
                    .CausedBy(decodeResult.Errors));

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

            var portfolios = await context.Portfolios.AsNoTracking()
                .Where(f => f.Id == decodeResult.Value)
                .OrderByDescending(o => o.CreatedAt)
                .ToListAsync(cancellationToken);

            return Result.Ok(portfolios.Select(p => p.Map()).ToArray());
        }));

    public async Task<Result<Organisation[]>> GetOrganisationsAsync(Pagination pagination, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result<Organisation[]>>>)(async () =>
        {
            await using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            var organisations = await context.TenantOrganisations.AsNoTracking()
                .Include(i => i.Organisation)
                .OrderBy(o => o.Organisation!.Name)
                .Skip((pagination.Page - 1) * pagination.PageSize)
                .Take(pagination.PageSize)
                .ToListAsync(cancellationToken);

            return Result.Ok(organisations.Select(o => o.Organisation!.Map()).ToArray());
        }));

    public async Task<Result<Organisation>> GetOrganisationAsync(string organisationIdHash, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result<Organisation>>>)(async () =>
        {
            var decodeResult = hashService.DecodeLongIdHash(organisationIdHash);

            if (decodeResult.IsFailed)
                return Result.Fail(IdDecodeError.Create()
                    .CausedBy(decodeResult.Errors));

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

            var tenantOrganisation = await context.TenantOrganisations.AsNoTracking()
                .Include(i => i.OrganisationId)
                .FirstOrDefaultAsync(o => o.OrganisationId == decodeResult.Value, cancellationToken);

            return Result.FailIf(tenantOrganisation is null, NotFoundError.New)
                .ToResult(tenantOrganisation!.Organisation!.Map());
        }));

    public async Task<Result<Instrument[]>> GetInstrumentsAsync(string programmeIdHash, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result<Instrument[]>>>)(async () =>
        {
            var decodeResult = hashService.DecodeLongIdHash(programmeIdHash);

            if (decodeResult.IsFailed)
                return Result.Fail(IdDecodeError.Create()
                    .CausedBy(decodeResult.Errors));

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

            var instruments = await context.Instruments.AsNoTracking()
                .Where(i => i.ProgrammeId == decodeResult.Value)
                .OrderByDescending(o => o.CreatedAt)
                .ToListAsync(cancellationToken);

            return Result.Ok(instruments.Select(i => i.Map()).ToArray());
        }));

    public async Task<Result<Dashboard>> GetDashboardAsync(CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result<Dashboard>>>)(async () =>
        {
            await using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            var totalPortfolioValue = await context.Awards.SumAsync(a => a.Amount, cancellationToken);
            var activeAwardsCount = await context.Awards.CountAsync(a => a.Status == ApprovalStatus.Approved, cancellationToken);

            var disbursedAmount = await context.Disbursements.Where(d => d.Status == ApprovalStatus.Approved)
                .SumAsync(d => d.Amount, cancellationToken);

            var totalProjects = await context.Projects.CountAsync(cancellationToken);
            var onTrackProjects = await context.Projects.CountAsync(p => p.Status == ApprovalStatus.Approved, cancellationToken);

            var onTrackPercentage = totalProjects > 0
                ? Math.Round((double)onTrackProjects / totalProjects * 100, 1)
                : 100.0;

            var atRiskCount = await context.Risks.CountAsync(r => r.Impact == RiskImpact.Critical || r.Impact == RiskImpact.Major, cancellationToken);

            var beneficiariesReached = await context.Beneficiaries.SumAsync(b => b.ReachedCount, cancellationToken);

            return Result.Ok(new Dashboard(totalPortfolioValue, activeAwardsCount,
                disbursedAmount, onTrackPercentage, atRiskCount, beneficiariesReached));
        }));

    public async Task<Result> CreateOrganisationAsync(CreateOrganisationRequest request, Guid userId, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result>>)(async () =>
        {
            await using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            var registrationNo = request.RegistrationNo.Clean();

            if (await context.Organisations.AnyAsync(o => o.RegistrationNo == registrationNo, cancellationToken))
                return Result.Fail(CreateError.Create("Organisation with the same registration number already exists"));

            var organisation = context.Organisations.Add(new Domain.Entities.Organisation
            {
                Name = request.Name.Humanize(LetterCasing.Title).Trim(),
                RegistrationNo = registrationNo,
                Email = request.Email.ToLower(CultureInfo.InvariantCulture).Clean(),
                Type = request.Type,
                Status = ActivityStatus.Active,
                CreatedBy = userId,
                CreatedAt = DateTime.UtcNow
            });

            await context.SaveChangesAsync(cancellationToken);

            var mapResult = await CreateTenantOrganisationAsync(hashService.HashEncodeLongId(organisation.Entity.Id).Value,
                hashService.HashEncodeLongId(tenantContext.TenantId).Value, userId, cancellationToken);

            return Result.FailIf(mapResult.IsFailed, CreateError.Create("Failed to create organisation"));
        }));

    public async Task<Result<Organisation>> UpdateOrganisationAsync(UpdateOrganisationRequest request, Guid userId, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result<Organisation>>>)(async () =>
        {
            await using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            var changedTotal = await context.Organisations
                .Where(f => f.Id == request.OrganisationId)
                .ExecuteUpdateAsync(f => f
                    .SetProperty(u => u.Name, request.Name.Humanize(LetterCasing.Title).Trim())
                    .SetProperty(u => u.RegistrationNo, request.RegistrationNo.Clean())
                    .SetProperty(u => u.Email, request.Email.ToLower(CultureInfo.InvariantCulture).Clean())
                    .SetProperty(u => u.Type, request.Type)
                    .SetProperty(u => u.Status, request.Status), cancellationToken);

            var tenantOrganisation = await context.TenantOrganisations.AsNoTracking().FirstOrDefaultAsync(f => f.OrganisationId == request.OrganisationId, cancellationToken);

            if (tenantOrganisation is null)
                return Result.Fail(ValidationError.Create("Failed to find linked tenant organisation"));

            var updateResult = await UpdateTenantOrganisationAsync(hashService.HashEncodeLongId(tenantOrganisation.Id).Value, request.Status, userId, cancellationToken);

            return Result.OkIf(changedTotal > 0 && updateResult.IsSuccess, UpdateError.Create("Failed to update organisation"));
        }));

    public async Task<Result> CreatePortfolioAsync(CreatePortfolioRequest request, Guid userId, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result>>)(async () =>
        {
            await using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            if (!await context.Users.AnyAsync(u => u.Id == request.OwnerId, cancellationToken))
                return Result.Fail(NotFoundError.Create("Owner user not found"));

            if (!await context.Organisations.AnyAsync(u => u.Id == request.OrganisationId, cancellationToken))
                return Result.Fail(NotFoundError.Create("Organisation not found"));

            var name = request.Name.Humanize(LetterCasing.Title).Trim();

            if (await context.Portfolios.AnyAsync(p => p.Name == name && p.OrganisationId == request.OrganisationId, cancellationToken))
                return Result.Fail(ValidationError.Create("A portfolio with the same name exists in this organisation"));

            context.Portfolios.Add(new Domain.Entities.Portfolio
            {
                CreatedAt = DateTime.UtcNow,
                CreatedBy = userId,
                OrganisationId = request.OrganisationId,
                OwnedBy = request.OwnerId,
                Name = name,
                Description = request.Description.Humanize(LetterCasing.Sentence).Trim(),
                TenantId = tenantContext.TenantId
            });

            return Result.OkIf(await context.SaveChangesAsync(cancellationToken) > 0, CreateError.New);
        }));

    public async Task<Result> UpdatePortfolioAsync(UpdatePortfolioRequest request, Guid userId, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result>>)(async () =>
        {
            await using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            if (!await context.Users.AnyAsync(u => u.Id == request.OwnerId, cancellationToken))
                return Result.Fail(NotFoundError.Create("Owner user not found"));

            var changedTotal = await context.Portfolios
                .Where(p => p.Id == request.PortfolioId)
                .ExecuteUpdateAsync(f => f
                    .SetProperty(u => u.Name, request.Name.Humanize(LetterCasing.Title).Trim())
                    .SetProperty(u => u.OwnedBy, request.OwnerId)
                    .SetProperty(u => u.Description, request.Description.Humanize(LetterCasing.Sentence).Trim()), cancellationToken);

            return Result.OkIf(changedTotal > 0, UpdateError.Create("Nothing was saved, no change detected."));
        }));

    public async Task<Result<Programme[]>> GetPortfolioProgrammesAsync(string portfolioIdHash, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result<Programme[]>>>)(async () =>
        {
            var decodeResult = hashService.DecodeLongIdHash(portfolioIdHash);

            if (decodeResult.IsFailed)
                return Result.Fail(IdDecodeError.Create()
                    .CausedBy(decodeResult.Errors));

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

            var programmes = await context.Programmes.AsNoTracking()
                .Where(f => f.PortfolioId == decodeResult.Value)
                .OrderByDescending(o => o.CreatedAt)
                .ToListAsync(cancellationToken);

            return Result.Ok(programmes.Select(p => p.Map()).ToArray());
        }));

    public async Task<Result<Portfolio>> GetPortfolioAsync(string portfolioIdHash, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result<Portfolio>>>)(async () =>
        {
            var decodeResult = hashService.DecodeLongIdHash(portfolioIdHash);

            if (decodeResult.IsFailed)
                return Result.Fail(IdDecodeError.Create()
                    .CausedBy(decodeResult.Errors));

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

            var portfolio = await context.Portfolios.AsNoTracking()
                .FirstOrDefaultAsync(p => p.Id == decodeResult.Value, cancellationToken);

            return Result.FailIf(portfolio is null, NotFoundError.New)
                .ToResult(portfolio!.Map());
        }));

    public async Task<Result> CreateTenantAsync(CreateTenantRequest request, Guid userId, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result>>)(async () =>
        {
            await using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            var requestedName = request.Name.Humanize(LetterCasing.Title).Trim();

            if (await context.Tenants.AnyAsync(t => t.Name == requestedName, cancellationToken))
                return Result.Fail(ValidationError.Create("A tenant with an equivalent name exists."));

            context.Tenants.Add(new Domain.Entities.Tenant
            {
                CreatedAt = DateTime.UtcNow,
                CreatedBy = userId,
                Name = requestedName,
                Status = ActivityStatus.Active
            });

            return Result.OkIf(await context.SaveChangesAsync(cancellationToken) > 0,
                CreateError.Create("Failed to create new tenant"));
        }));

    public async Task<Result<Tenant[]>> GetTenantsAsync(CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result<Tenant[]>>>)(async () =>
        {
            await using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            var tenants = await context.Tenants.AsNoTracking()
                .OrderByDescending(o => o.Id)
                .ToListAsync(cancellationToken);

            return Result.Ok(tenants?.Select(t => t.Map()).ToArray() ?? []);
        }));

    public async Task<Result<Tenant>> GetTenantAsync(string tenantIdHash, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result<Tenant>>>)(async () =>
        {
            var decodeResult = hashService.DecodeLongIdHash(tenantIdHash);

            if (decodeResult.IsFailed)
                return Result.Fail(IdDecodeError.Create()
                    .CausedBy(decodeResult.Errors));

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

            var tenant = await context.Tenants.AsNoTracking().FirstOrDefaultAsync(t => t.Id == decodeResult.Value, cancellationToken);

            return Result.FailIf(tenant is null, NotFoundError.Create("Failed to retrieve tenants"))
                .ToResult(tenant!.Map());
        }));

    public async Task<Result> UpdateTenantAsync(UpdateTenantRequest request, Guid userId, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result>>)(async () =>
        {
            await using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            var requestedName = request.Name.Humanize(LetterCasing.Title).Trim();

            if (await context.Tenants.AnyAsync(t => t.Name == requestedName, cancellationToken))
                return Result.Fail(ValidationError.Create("A tenant with an equivalent name exists."));

            var changedTotal = await context.Tenants
                .Where(f => f.Id == request.TenantId)
                .ExecuteUpdateAsync(f => f
                    .SetProperty(u => u.UpdatedAt, DateTime.UtcNow)
                    .SetProperty(u => u.UpdatedBy, userId)
                    .SetProperty(u => u.Status, request.Status)
                    .SetProperty(u => u.Name, requestedName), cancellationToken);

            return Result.OkIf(changedTotal > 0, UpdateError.Create("No records updated"));
        }));

    public async Task<Result> UpdateTenantUserAsync(UpdateTenantUserRequest request, Guid userId, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result>>)(async () =>
        {
            await using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            var changedTotal = await context.TenantUsers
                .Where(f => f.UserId == request.UserId)
                .ExecuteUpdateAsync(f => f.SetProperty(u => u.Status, request.Status), cancellationToken);

            return Result.OkIf(changedTotal > 0, UpdateError.Create("No records updated"));
        }));

    public async Task<Result> CreateTenantOrganisationAsync(string organisationIdHash, string tenantIdHash, Guid userId, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result>>)(async () =>
        {
            var organisationDecodeResult = hashService.DecodeLongIdHash(organisationIdHash);

            if (organisationDecodeResult.IsFailed)
                return Result.Fail(IdDecodeError.Create()
                    .CausedBy(organisationDecodeResult.Errors));

            var tenantDecodeResult = hashService.DecodeLongIdHash(tenantIdHash);

            if (tenantDecodeResult.IsFailed)
                return Result.Fail(IdDecodeError.Create()
                    .CausedBy(tenantDecodeResult.Errors));

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

            if (await context.TenantOrganisations.AnyAsync(to => to.OrganisationId == organisationDecodeResult.Value && to.TenantId == tenantDecodeResult.Value, cancellationToken))
                return Result.Fail(ValidationError.Create("Already exists"));

            context.TenantOrganisations.Add(new Domain.Entities.TenantOrganisation
            {
                CreatedAt = DateTime.UtcNow,
                CreatedBy = userId,
                OrganisationId = organisationDecodeResult.Value,
                TenantId = tenantDecodeResult.ValueOrDefault
            });

            return Result.OkIf(await context.SaveChangesAsync(cancellationToken) > 0,
                CreateError.Create("Failed to create tenant organisation map"));
        }));

    public async Task<Result> UpdateTenantOrganisationAsync(string tenantOrganisationIdHash, ActivityStatus status, Guid userId, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result>>)(async () =>
        {
            var decodeResult = hashService.DecodeLongIdHash(tenantOrganisationIdHash);

            if (decodeResult.IsFailed)
                return Result.Fail(IdDecodeError.Create()
                    .CausedBy(decodeResult.Errors));

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

            var changedTotal = await context.TenantOrganisations
                .Where(f => f.Id == decodeResult.Value)
                .ExecuteUpdateAsync(f => f.SetProperty(u => u.Status, status), cancellationToken);

            return Result.OkIf(changedTotal > 0, UpdateError.Create("Failed to update tenant organisation map"));
        }));

    public async Task<Result<TenantOrganisation[]>> GetTenantOrganisationsAsync(CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result<TenantOrganisation[]>>>)(async () =>
        {
            await using var context = await contextFactory.CreateDbContextAsync(cancellationToken);

            var tenantOrganisations = await context.TenantOrganisations.AsNoTracking()
                .Include(i => i.Organisation)
                .Include(i => i.Tenant)
                .Where(f => f.TenantId == tenantContext.TenantId)
                .ToListAsync();

            return Result.Ok(tenantOrganisations?.Select(i => i.Map()).ToArray() ?? []);
        }));

    public async Task<Result<TenantOrganisation>> GetTenantOrganisationAsync(string tenantOrganisationIdHash, CancellationToken cancellationToken = default) =>
        await Result.Try((Func<Task<Result<TenantOrganisation>>>)(async () =>
        {
            var decodeResult = hashService.DecodeLongIdHash(tenantOrganisationIdHash);

            if (decodeResult.IsFailed)
                return Result.Fail(IdDecodeError.Create()
                    .CausedBy(decodeResult.Errors));

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

            var tenantOrganisation = await context.TenantOrganisations.AsNoTracking()
                .Include(i => i.Organisation)
                .Include(i => i.Tenant)
                .FirstOrDefaultAsync(f => f.TenantId == tenantContext.TenantId, cancellationToken);

            return Result.FailIf(tenantOrganisation is null, NotFoundError.Create("Failed to find tenant organisation map"))
                .ToResult(tenantOrganisation!.Map());
        }));
}