package network

import (
	"context"
	"errors"
	"time"

	"github.com/itworx/pulse/internal/host"
	"github.com/itworx/pulse/internal/service"
)

type Aggregator struct {
	Host     host.Provider
	Services service.Provider
	Limits   Limits
	Now      func() time.Time
}

func (a Aggregator) Snapshot(ctx context.Context) (Snapshot, error) {
	if ctx == nil {
		return Snapshot{}, errors.New("network context is nil")
	}
	if err := ctx.Err(); err != nil {
		return Snapshot{}, err
	}
	now := time.Now().UTC()
	if a.Now != nil {
		now = a.Now().UTC()
	}
	hostSnapshot := host.UnknownSnapshot(now, "host", "agent", "source_unavailable")
	if a.Host != nil {
		next, err := a.Host.Snapshot(ctx)
		if err != nil {
			if errors.Is(err, context.Canceled) || errors.Is(err, context.DeadlineExceeded) {
				return Snapshot{}, err
			}
			hostSnapshot = host.UnknownSnapshot(now, "host", "agent", "source_unavailable")
		} else {
			hostSnapshot = next
		}
	}
	serviceSnapshot := service.UnknownSnapshot(now, "source_unavailable")
	if a.Services != nil {
		next, err := a.Services.Snapshot(ctx)
		if err != nil {
			if errors.Is(err, context.Canceled) || errors.Is(err, context.DeadlineExceeded) {
				return Snapshot{}, err
			}
			serviceSnapshot = service.UnknownSnapshot(now, "source_unavailable")
		} else {
			serviceSnapshot = next
		}
	}
	return BuildSnapshot(now, hostSnapshot, serviceSnapshot, nil, nil, a.Limits)
}