package watcher

import (
	"context"
	"log/slog"
	"time"

	"sneak.berlin/go/dnswatcher/internal/config"
	"sneak.berlin/go/dnswatcher/internal/resolver"
	"sneak.berlin/go/dnswatcher/internal/state"
)

// NewForTest creates a Watcher without fx for unit testing. A nil cfg
// is an empty configuration.
func NewForTest(
	cfg *config.Config,
	st *state.State,
	res DNSResolver,
	pc PortChecker,
	tc TLSChecker,
	n Notifier,
) *Watcher {
	if cfg == nil {
		cfg = &config.Config{}
	}

	return &Watcher{
		log:       slog.Default(),
		config:    cfg,
		state:     st,
		resolver:  res,
		portCheck: pc,
		tlsCheck:  tc,
		notify:    n,
		firstRun:  true,
	}
}

// SetLogger replaces the watcher's logger, so a test can read what it
// logs.
func (w *Watcher) SetLogger(log *slog.Logger) {
	w.log = log
}

// NewlyDisagreeingPairs exports newlyDisagreeingPairs for testing.
func NewlyDisagreeingPairs(
	prev, current *state.HostnameState,
) [][2]string {
	return newlyDisagreeingPairs(prev, current)
}

// SetFirstRun sets whether the watcher is on its first check, in which
// nothing is compared with the previous check. NewForTest's watcher is.
func (w *Watcher) SetFirstRun(firstRun bool) {
	w.firstRun = firstRun
}

// UpdateHostnameState exports updateHostnameState for testing.
func (w *Watcher) UpdateHostnameState(
	ctx context.Context,
	hostname string,
	newState *state.HostnameState,
) {
	w.updateHostnameState(ctx, hostname, newState)
}

// DetectHostnameChanges exports detectHostnameChanges for testing.
func (w *Watcher) DetectHostnameChanges(
	ctx context.Context,
	hostname string,
	prev, current *state.HostnameState,
) {
	w.detectHostnameChanges(ctx, hostname, prev, current)
}

// ResolveNameserverAddresses exports resolveNameserverAddresses for
// testing.
func (w *Watcher) ResolveNameserverAddresses(
	ctx context.Context,
	nameservers []string,
	prev map[string][]string,
) map[string][]string {
	return w.resolveNameserverAddresses(ctx, nameservers, prev)
}

// ResolveCNAMEAddresses exports resolveCNAMEAddresses for testing.
func (w *Watcher) ResolveCNAMEAddresses(
	ctx context.Context,
	hostname string,
	current, prev *state.HostnameState,
) {
	w.resolveCNAMEAddresses(ctx, hostname, current, prev)
}

// DetectNSAddressChanges exports detectNSAddressChanges for testing.
func (w *Watcher) DetectNSAddressChanges(
	ctx context.Context,
	domain string,
	prev, current map[string][]string,
) {
	w.detectNSAddressChanges(ctx, domain, prev, current)
}

// MaybeSendTestNotification exports maybeSendTestNotification for
// testing.
func (w *Watcher) MaybeSendTestNotification(ctx context.Context) {
	w.maybeSendTestNotification(ctx)
}

// CheckAllPorts exports checkAllPorts for testing.
func (w *Watcher) CheckAllPorts(ctx context.Context) {
	w.checkAllPorts(ctx)
}

// RunTLSChecks exports runTLSChecks for testing.
func (w *Watcher) RunTLSChecks(ctx context.Context) {
	w.runTLSChecks(ctx)
}

// BuildHostnameState exports buildHostnameState for testing.
func BuildHostnameState(
	results map[string]*resolver.NameserverResponse,
	now time.Time,
) *state.HostnameState {
	return buildHostnameState(results, now)
}