package app

import (
	"context"
	"strings"
	"testing"

	"gitea.maximumdirect.net/eric/distributor/internal/config"
	"gitea.maximumdirect.net/eric/distributor/internal/storage"
	"gitea.maximumdirect.net/eric/distributor/internal/storage/fake"
)

func TestBackendFactoryOpensLocalSource(t *testing.T) {
	factory := newBackendFactory()
	backend, err := factory.openSource(context.Background(), config.Backend{
		Backend: config.BackendLocal,
		Path:    t.TempDir(),
	})
	if err != nil {
		t.Fatalf("openSource() error = %v", err)
	}
	if backend == nil {
		t.Fatal("openSource() backend = nil")
	}
}

func TestBackendFactoryOpensLocalDestination(t *testing.T) {
	factory := newBackendFactory()
	backend, err := factory.openDestination(context.Background(), config.Destination{
		Backend: config.BackendLocal,
		Path:    t.TempDir(),
	})
	if err != nil {
		t.Fatalf("openDestination() error = %v", err)
	}
	if backend == nil {
		t.Fatal("openDestination() backend = nil")
	}
}

func TestBackendFactoryOpensDirectLocalPath(t *testing.T) {
	factory := newBackendFactory()
	backend, err := factory.openLocalPath(context.Background(), t.TempDir())
	if err != nil {
		t.Fatalf("openLocalPath() error = %v", err)
	}
	if backend == nil {
		t.Fatal("openLocalPath() backend = nil")
	}
}

func TestBackendFactoryOpensSSHSourceWithRegisteredOpener(t *testing.T) {
	factory := &backendFactory{registry: storage.NewRegistry()}
	var got storage.OpenConfig
	if err := factory.registry.Register(config.BackendSSH, func(ctx context.Context, cfg storage.OpenConfig) (storage.Backend, error) {
		got = cfg
		return fake.New(), nil
	}); err != nil {
		t.Fatalf("Register() error = %v", err)
	}

	backend, err := factory.openSource(context.Background(), config.Backend{
		Backend: config.BackendSSH,
		Host:    "source.example.com",
		User:    "reports",
		Port:    22,
		Path:    "/reports",
		SSH:     config.SSH{HostKeyPolicy: config.HostKeyPolicyAcceptNew},
	})
	if err != nil {
		t.Fatalf("openSource() error = %v", err)
	}
	if backend == nil {
		t.Fatal("openSource() backend = nil")
	}
	if got[sshHostKey] != "source.example.com" || got[storagePathKey] != "/reports" {
		t.Fatalf("open config = %#v, want SSH source fields", got)
	}
}

func TestBackendFactoryOpensSSHDestinationWithRegisteredOpener(t *testing.T) {
	factory := &backendFactory{registry: storage.NewRegistry()}
	var got storage.OpenConfig
	if err := factory.registry.Register(config.BackendSSH, func(ctx context.Context, cfg storage.OpenConfig) (storage.Backend, error) {
		got = cfg
		return fake.New(), nil
	}); err != nil {
		t.Fatalf("Register() error = %v", err)
	}

	backend, err := factory.openDestination(context.Background(), config.Destination{
		Backend: config.BackendSSH,
		Host:    "destination.example.com",
		User:    "deploy",
		Port:    2222,
		Path:    "/archive",
		SSH:     config.SSH{HostKeyPolicy: config.HostKeyPolicyStrict},
	})
	if err != nil {
		t.Fatalf("openDestination() error = %v", err)
	}
	if backend == nil {
		t.Fatal("openDestination() backend = nil")
	}
	if got[sshHostKey] != "destination.example.com" || got[sshPortKey] != "2222" || got[sshHostKeyPolicyKey] != "strict" {
		t.Fatalf("open config = %#v, want SSH destination fields", got)
	}
}

func TestBackendFactorySetsReadOnlyKnownHostsForDryRunSSH(t *testing.T) {
	factory := &backendFactory{
		registry:           storage.NewRegistry(),
		readOnlyKnownHosts: true,
	}
	var got storage.OpenConfig
	if err := factory.registry.Register(config.BackendSSH, func(ctx context.Context, cfg storage.OpenConfig) (storage.Backend, error) {
		got = cfg
		return fake.New(), nil
	}); err != nil {
		t.Fatalf("Register() error = %v", err)
	}

	_, err := factory.openDestination(context.Background(), config.Destination{
		Backend: config.BackendSSH,
		Host:    "destination.example.com",
		User:    "deploy",
		Port:    22,
		Path:    "/archive",
		SSH:     config.SSH{HostKeyPolicy: config.HostKeyPolicyAcceptNew},
	})
	if err != nil {
		t.Fatalf("openDestination() error = %v", err)
	}
	if got[sshReadOnlyHostsKey] != "true" {
		t.Fatalf("open config %s = %q, want true", sshReadOnlyHostsKey, got[sshReadOnlyHostsKey])
	}
}

func TestBackendFactoryUsesPersistentKnownHostsByDefault(t *testing.T) {
	factory := &backendFactory{registry: storage.NewRegistry()}
	var got storage.OpenConfig
	if err := factory.registry.Register(config.BackendSSH, func(ctx context.Context, cfg storage.OpenConfig) (storage.Backend, error) {
		got = cfg
		return fake.New(), nil
	}); err != nil {
		t.Fatalf("Register() error = %v", err)
	}

	_, err := factory.openDestination(context.Background(), config.Destination{
		Backend: config.BackendSSH,
		Host:    "destination.example.com",
		User:    "deploy",
		Port:    22,
		Path:    "/archive",
		SSH:     config.SSH{HostKeyPolicy: config.HostKeyPolicyAcceptNew},
	})
	if err != nil {
		t.Fatalf("openDestination() error = %v", err)
	}
	if got[sshReadOnlyHostsKey] != "false" {
		t.Fatalf("open config %s = %q, want false", sshReadOnlyHostsKey, got[sshReadOnlyHostsKey])
	}
}

func TestBackendFactoryRejectsUnsupportedSource(t *testing.T) {
	factory := newBackendFactory()
	_, err := factory.openSource(context.Background(), config.Backend{
		Backend: "ftp",
	})
	if err == nil || !strings.Contains(err.Error(), "source backend ftp is not implemented for execution") {
		t.Fatalf("openSource() error = %v, want not implemented", err)
	}
}

func TestBackendFactoryRejectsUnsupportedDestination(t *testing.T) {
	factory := newBackendFactory()
	_, err := factory.openDestination(context.Background(), config.Destination{
		Backend: "ftp",
	})
	if err == nil || !strings.Contains(err.Error(), "backend ftp is not implemented for execution") {
		t.Fatalf("openDestination() error = %v, want not implemented", err)
	}
}

func TestBackendFactoryOpensS3DestinationWithRegisteredOpener(t *testing.T) {
	factory := &backendFactory{
		registry:    storage.NewRegistry(),
		environment: config.NewEnvironment(nil, func(string) (string, bool) { return "", false }),
	}
	var got storage.OpenConfig
	if err := factory.registry.Register(config.BackendS3, func(ctx context.Context, cfg storage.OpenConfig) (storage.Backend, error) {
		got = cfg
		return fake.New(), nil
	}); err != nil {
		t.Fatalf("Register() error = %v", err)
	}
	forcePathStyle := false
	backend, err := factory.openDestination(context.Background(), config.Destination{
		Backend:   config.BackendS3,
		Endpoint:  "https://s3.example.com",
		Bucket:    "reports",
		Prefix:    "archive",
		Region:    config.DefaultS3Region,
		ForcePath: &forcePathStyle,
	})
	if err != nil {
		t.Fatalf("openDestination() error = %v", err)
	}
	if backend == nil {
		t.Fatal("openDestination() backend = nil")
	}
	assertOpenConfig(t, got, map[string]string{
		s3EndpointKey:       "https://s3.example.com",
		s3BucketKey:         "reports",
		s3PrefixKey:         "archive",
		s3RegionKey:         config.DefaultS3Region,
		s3ForcePathStyleKey: "false",
	})
}

func TestBackendFactoryResolvesS3CredentialsThroughSecretsAwareEnvironment(t *testing.T) {
	factory := &backendFactory{
		registry: storage.NewRegistry(),
		environment: config.NewEnvironment(map[string]string{
			"ACCESS_KEY_ID":     "secret-access",
			"SECRET_ACCESS_KEY": "secret-secret",
		}, func(string) (string, bool) { return "", false }),
	}
	var got storage.OpenConfig
	if err := factory.registry.Register(config.BackendS3, func(ctx context.Context, cfg storage.OpenConfig) (storage.Backend, error) {
		got = cfg
		return fake.New(), nil
	}); err != nil {
		t.Fatalf("Register() error = %v", err)
	}
	forcePathStyle := true
	_, err := factory.openSource(context.Background(), config.Backend{
		Backend:   config.BackendS3,
		Endpoint:  "https://s3.example.com",
		Bucket:    "reports",
		Region:    config.DefaultS3Region,
		ForcePath: &forcePathStyle,
		Creds: config.Credentials{
			AccessKeyIDEnv:     "ACCESS_KEY_ID",
			SecretAccessKeyEnv: "SECRET_ACCESS_KEY",
		},
	})
	if err != nil {
		t.Fatalf("openSource() error = %v", err)
	}
	assertOpenConfig(t, got, map[string]string{
		s3AccessKeyIDKey:  "secret-access",
		s3SecretAccessKey: "secret-secret",
	})
}

func TestBackendFactoryResolvesCredentialsThroughEnvironment(t *testing.T) {
	factory := newBackendFactoryWithEnvironment(config.NewEnvironment(map[string]string{
		"ACCESS_KEY_ID":     "secret-access",
		"SECRET_ACCESS_KEY": "secret-secret",
	}, func(string) (string, bool) {
		return "", false
	}))

	creds, err := factory.resolveCredentials(config.Credentials{
		AccessKeyIDEnv:     "ACCESS_KEY_ID",
		SecretAccessKeyEnv: "SECRET_ACCESS_KEY",
	})
	if err != nil {
		t.Fatalf("resolveCredentials() error = %v", err)
	}
	if creds.AccessKeyID != "secret-access" || creds.SecretAccessKey != "secret-secret" {
		t.Fatalf("resolved credentials = %#v", creds)
	}
}

func TestBackendFactoryBuildsSSHSourceOpenConfig(t *testing.T) {
	cfg := sourceOpenConfig(config.Backend{
		Backend: config.BackendSSH,
		Host:    "source.example.com",
		User:    "reports",
		Port:    2222,
		Path:    "/reports",
		SSH: config.SSH{
			KeyFile:       "/home/reports/.ssh/id_ed25519",
			KnownHosts:    "/home/reports/.ssh/known_hosts",
			HostKeyPolicy: config.HostKeyPolicyStrict,
		},
	})

	assertOpenConfig(t, cfg, map[string]string{
		storagePathKey:      "/reports",
		sshHostKey:          "source.example.com",
		sshUserKey:          "reports",
		sshPortKey:          "2222",
		sshKeyFileKey:       "/home/reports/.ssh/id_ed25519",
		sshKnownHostsKey:    "/home/reports/.ssh/known_hosts",
		sshHostKeyPolicyKey: "strict",
	})
}

func TestBackendFactoryBuildsSSHDestinationOpenConfig(t *testing.T) {
	cfg := destinationOpenConfig(config.Destination{
		Backend: config.BackendSSH,
		Host:    "destination.example.com",
		User:    "deploy",
		Port:    22,
		Path:    "/srv/archive",
		SSH: config.SSH{
			HostKeyPolicy: config.HostKeyPolicyAcceptNew,
		},
	})

	assertOpenConfig(t, cfg, map[string]string{
		storagePathKey:      "/srv/archive",
		sshHostKey:          "destination.example.com",
		sshUserKey:          "deploy",
		sshPortKey:          "22",
		sshHostKeyPolicyKey: "accept-new",
	})
}

func assertOpenConfig(t *testing.T, got map[string]string, want map[string]string) {
	t.Helper()
	for key, wantValue := range want {
		if gotValue := got[key]; gotValue != wantValue {
			t.Fatalf("open config %s = %q, want %q", key, gotValue, wantValue)
		}
	}
}