package aghtest

import (
	"context"
	"io"
	"io/fs"
	"net/netip"

	"github.com/AdguardTeam/AdGuardHome/internal/aghos"
	"github.com/AdguardTeam/AdGuardHome/internal/client"
	"github.com/AdguardTeam/AdGuardHome/internal/next/agh"
	"github.com/AdguardTeam/AdGuardHome/internal/rdns"
	"github.com/AdguardTeam/AdGuardHome/internal/whois"
	"github.com/AdguardTeam/dnsproxy/upstream"
	"github.com/miekg/dns"
)

// Interface Mocks
//
// Keep entities in this file in alphabetic order.

// Standard Library

// Package fs

// FS is a fake [fs.FS] implementation for tests.
type FS struct {
	OnOpen func(name string) (fs.File, error)
}

// type check
var _ fs.FS = (*FS)(nil)

// Open implements the [fs.FS] interface for *FS.
func (fsys *FS) Open(name string) (fs.File, error) {
	return fsys.OnOpen(name)
}

// type check
var _ fs.GlobFS = (*GlobFS)(nil)

// GlobFS is a fake [fs.GlobFS] implementation for tests.
type GlobFS struct {
	// FS is embedded here to avoid implementing all it's methods.
	FS
	OnGlob func(pattern string) ([]string, error)
}

// Glob implements the [fs.GlobFS] interface for *GlobFS.
func (fsys *GlobFS) Glob(pattern string) ([]string, error) {
	return fsys.OnGlob(pattern)
}

// type check
var _ fs.StatFS = (*StatFS)(nil)

// StatFS is a fake [fs.StatFS] implementation for tests.
type StatFS struct {
	// FS is embedded here to avoid implementing all it's methods.
	FS
	OnStat func(name string) (fs.FileInfo, error)
}

// Stat implements the [fs.StatFS] interface for *StatFS.
func (fsys *StatFS) Stat(name string) (fs.FileInfo, error) {
	return fsys.OnStat(name)
}

// Package io

// Writer is a fake [io.Writer] implementation for tests.
type Writer struct {
	OnWrite func(b []byte) (n int, err error)
}

var _ io.Writer = (*Writer)(nil)

// Write implements the [io.Writer] interface for *Writer.
func (w *Writer) Write(b []byte) (n int, err error) {
	return w.OnWrite(b)
}

// Module adguard-home

// Package aghos

// FSWatcher is a fake [aghos.FSWatcher] implementation for tests.
type FSWatcher struct {
	OnEvents func() (e <-chan struct{})
	OnAdd    func(name string) (err error)
	OnClose  func() (err error)
}

// type check
var _ aghos.FSWatcher = (*FSWatcher)(nil)

// Events implements the [aghos.FSWatcher] interface for *FSWatcher.
func (w *FSWatcher) Events() (e <-chan struct{}) {
	return w.OnEvents()
}

// Add implements the [aghos.FSWatcher] interface for *FSWatcher.
func (w *FSWatcher) Add(name string) (err error) {
	return w.OnAdd(name)
}

// Close implements the [aghos.FSWatcher] interface for *FSWatcher.
func (w *FSWatcher) Close() (err error) {
	return w.OnClose()
}

// Package agh

// ServiceWithConfig is a fake [agh.ServiceWithConfig] implementation for tests.
type ServiceWithConfig[ConfigType any] struct {
	OnStart    func() (err error)
	OnShutdown func(ctx context.Context) (err error)
	OnConfig   func() (c ConfigType)
}

// type check
var _ agh.ServiceWithConfig[struct{}] = (*ServiceWithConfig[struct{}])(nil)

// Start implements the [agh.ServiceWithConfig] interface for
// *ServiceWithConfig.
func (s *ServiceWithConfig[_]) Start() (err error) {
	return s.OnStart()
}

// Shutdown implements the [agh.ServiceWithConfig] interface for
// *ServiceWithConfig.
func (s *ServiceWithConfig[_]) Shutdown(ctx context.Context) (err error) {
	return s.OnShutdown(ctx)
}

// Config implements the [agh.ServiceWithConfig] interface for
// *ServiceWithConfig.
func (s *ServiceWithConfig[ConfigType]) Config() (c ConfigType) {
	return s.OnConfig()
}

// Package client

// AddressProcessor is a fake [client.AddressProcessor] implementation for
// tests.
type AddressProcessor struct {
	OnProcess func(ip netip.Addr)
	OnClose   func() (err error)
}

// type check
var _ client.AddressProcessor = (*AddressProcessor)(nil)

// Process implements the [client.AddressProcessor] interface for
// *AddressProcessor.
func (p *AddressProcessor) Process(ip netip.Addr) {
	p.OnProcess(ip)
}

// Close implements the [client.AddressProcessor] interface for
// *AddressProcessor.
func (p *AddressProcessor) Close() (err error) {
	return p.OnClose()
}

// AddressUpdater is a fake [client.AddressUpdater] implementation for tests.
type AddressUpdater struct {
	OnUpdateAddress func(ip netip.Addr, host string, info *whois.Info)
}

// type check
var _ client.AddressUpdater = (*AddressUpdater)(nil)

// UpdateAddress implements the [client.AddressUpdater] interface for
// *AddressUpdater.
func (p *AddressUpdater) UpdateAddress(ip netip.Addr, host string, info *whois.Info) {
	p.OnUpdateAddress(ip, host, info)
}

// Package rdns

// Exchanger is a fake [rdns.Exchanger] implementation for tests.
type Exchanger struct {
	OnExchange func(ip netip.Addr) (host string, err error)
}

// type check
var _ rdns.Exchanger = (*Exchanger)(nil)

// Exchange implements [rdns.Exchanger] interface for *Exchanger.
func (e *Exchanger) Exchange(ip netip.Addr) (host string, err error) {
	return e.OnExchange(ip)
}

// Module dnsproxy

// Package upstream

// UpstreamMock is a fake [upstream.Upstream] implementation for tests.
//
// TODO(a.garipov): Replace with all uses of Upstream with UpstreamMock and
// rename it to just Upstream.
type UpstreamMock struct {
	OnAddress  func() (addr string)
	OnExchange func(req *dns.Msg) (resp *dns.Msg, err error)
	OnClose    func() (err error)
}

// type check
var _ upstream.Upstream = (*UpstreamMock)(nil)

// Address implements the [upstream.Upstream] interface for *UpstreamMock.
func (u *UpstreamMock) Address() (addr string) {
	return u.OnAddress()
}

// Exchange implements the [upstream.Upstream] interface for *UpstreamMock.
func (u *UpstreamMock) Exchange(req *dns.Msg) (resp *dns.Msg, err error) {
	return u.OnExchange(req)
}

// Close implements the [upstream.Upstream] interface for *UpstreamMock.
func (u *UpstreamMock) Close() (err error) {
	return u.OnClose()
}