package cabana

import (
	"context"
	"encoding/json"
	"errors"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"testing/fstest"

	"git.golem15.com/golem15/summercms/modules/compass"
	"git.golem15.com/golem15/summercms/modules/lagoon"
	"git.golem15.com/golem15/summercms/modules/pact"
)

// secretSettings is a settings model with one lagoon.Encrypted column and
// one plain string column, for the write-only password compile gate.
type secretSettings struct {
	ID     uint             `gorm:"column:id;primaryKey"`
	APIKey lagoon.Encrypted `gorm:"column:api_key;type:text"`
	Token  string           `gorm:"column:token"`
	Notes  string           `gorm:"column:notes"`
}

func (secretSettings) TableName() string        { return "cabana_secret_settings" }
func (secretSettings) Fillable() []string       { return []string{"api_key", "token", "notes"} }
func (secretSettings) Rules() map[string]string { return map[string]string{} }

// SecretFallbacks maps each secret field to the config key the application
// reads when the column is empty; SUMMER_* variables map onto those keys.
func (secretSettings) SecretFallbacks() map[string]string {
	return map[string]string{"api_key": "acme.secret.api_key"}
}

func secretSettingsItem(fields string) (pact.SettingsItem, fstest.MapFS) {
	fsys := fstest.MapFS{"models/settings/fields.yaml": &fstest.MapFile{Data: []byte(fields)}}
	item := pact.SettingsItem{Code: "secret", Label: "Secret", Form: "models/settings/fields.yaml", Model: "SecretSettings", NewModel: func() any { return &secretSettings{} }}
	return item, fsys
}

// TestSettingsSecretCompile checks the D-13 boot gate without a database: a
// password field on a settings form binds a lagoon.Encrypted column as a
// write-only secret, keeps its tab, and is refused on any other column type
// naming the field.
func TestSettingsSecretCompile(t *testing.T) {
	item, fsys := secretSettingsItem("fields:\n    api_key:\n        label: API key\n        type: password\n        tab: Keys\n    notes:\n        type: richeditor\n")
	setting, err := compileSetting("acme.unit", item, fsys)
	if err != nil {
		t.Fatal(err)
	}
	if len(setting.Secrets) != 1 || setting.Secrets[0] != "api_key" {
		t.Fatalf("secrets = %v", setting.Secrets)
	}
	names := map[string]bool{}
	for _, w := range setting.Writable {
		names[w.Name] = true
	}
	if !names["api_key"] || !names["notes"] {
		t.Fatalf("writable = %+v", setting.Writable)
	}
	if setting.Form.Fields[0].Tab != "Keys" {
		t.Fatalf("tab dropped: %+v", setting.Form.Fields[0])
	}
	data := withoutSecrets(setting, map[string]any{"api_key": lagoon.NewEncrypted("x"), "notes": "n"})
	if _, leaked := data["api_key"]; leaked || data["notes"] != "n" {
		t.Fatalf("projection = %#v", data)
	}
	if (secretSettings{}).SecretFallbacks()["api_key"] != "acme.secret.api_key" {
		t.Fatal("fallback key")
	}
	states := secretStates(setting, &secretSettings{}, nil)
	if states["api_key"] != SecretEmpty {
		t.Fatalf("states = %v", states)
	}
	states = secretStates(setting, &secretSettings{APIKey: lagoon.NewEncrypted("sk")}, nil)
	if states["api_key"] != SecretStored {
		t.Fatalf("states = %v", states)
	}

	item, fsys = secretSettingsItem("fields:\n    token:\n        type: password\n")
	_, err = compileSetting("acme.unit", item, fsys)
	if err == nil || !strings.Contains(err.Error(), "field token: password on a settings form needs a lagoon.Encrypted column") {
		t.Fatalf("password on a string column: %v", err)
	}

	body := map[string]any{"api_key": "", "notes": "n"}
	if err := liftSecretValues(setting, body); err != nil {
		t.Fatal(err)
	}
	if _, kept := body["api_key"]; kept {
		t.Fatalf("empty string did not keep the stored value: %#v", body)
	}
	body = map[string]any{"api_key": nil}
	if err := liftSecretValues(setting, body); err != nil {
		t.Fatal(err)
	}
	if value, present := body["api_key"]; !present || value != nil {
		t.Fatalf("null did not stay as the clear: %#v", body)
	}
	if err := liftSecretValues(setting, map[string]any{"api_key": 5}); err == nil {
		t.Fatal("a non-string secret was accepted")
	}
}

// secretTwoFields compiles the unit settings form with the secret on the
// Keys tab, an untabbed plain token text field and a richeditor.
func secretTwoFields(t *testing.T) *CompiledSetting {
	t.Helper()
	item, fsys := secretSettingsItem("fields:\n    api_key:\n        label: API key\n        type: password\n        tab: Keys\n    token:\n        type: text\n    notes:\n        type: richeditor\n")
	setting, err := compileSetting("acme.unit", item, fsys)
	if err != nil {
		t.Fatal(err)
	}
	return setting
}

// secretConfig is a compass config whose environment sets the given
// SUMMER_* variables.
func secretConfig(t *testing.T, environ ...string) *compass.Config {
	t.Helper()
	dir := t.TempDir()
	if err := os.WriteFile(filepath.Join(dir, "app.yaml"), []byte("name: cabana-secrets\nlocale: en\n"), 0o644); err != nil {
		t.Fatal(err)
	}
	cfg, err := compass.Open(compass.Options{Dir: dir, Environ: environ})
	if err != nil {
		t.Fatal(err)
	}
	return cfg
}

// TestSettingsSecretProjection checks the D-13 read side without a
// database: the data projection never carries a password field (whatever
// it holds), every other column stays; the three states stored, env and
// empty come from the model and the fallback config key; the meta is
// omitted from the JSON when there is nothing to report; and no marshalled
// result contains the plaintext.
func TestSettingsSecretProjection(t *testing.T) {
	setting := secretTwoFields(t)
	const plaintext = "sk_live_projection"
	model := &secretSettings{APIKey: lagoon.NewEncrypted(plaintext), Token: "tok", Notes: "<p>n</p>"}
	data := withoutSecrets(setting, projectSetting(setting, model))
	if _, leaked := data["api_key"]; leaked {
		t.Fatalf("api_key in data: %#v", data)
	}
	if data["token"] != "tok" || data["notes"] != "<p>n</p>" {
		t.Fatalf("other columns dropped: %#v", data)
	}

	envCfg := secretConfig(t, "SUMMER_ACME__SECRET__API_KEY=sk_env_value")
	emptyCfg := secretConfig(t)
	for _, tc := range []struct {
		name  string
		model *secretSettings
		cfg   *compass.Config
		want  string
	}{
		{"stored without config", &secretSettings{APIKey: lagoon.NewEncrypted(plaintext)}, nil, SecretStored},
		{"stored wins over env", &secretSettings{APIKey: lagoon.NewEncrypted(plaintext)}, envCfg, SecretStored},
		{"env when the column is empty", &secretSettings{}, envCfg, SecretEnv},
		{"empty when the fallback is unset", &secretSettings{}, emptyCfg, SecretEmpty},
		{"empty without config", &secretSettings{}, nil, SecretEmpty},
	} {
		t.Run(tc.name, func(t *testing.T) {
			states := secretStates(setting, tc.model, tc.cfg)
			if len(states) != 1 || states["api_key"] != tc.want {
				t.Fatalf("states = %v, want api_key %s", states, tc.want)
			}
			result := SettingsResult{Exists: true, Data: withoutSecrets(setting, projectSetting(setting, tc.model)), Meta: settingsMeta(context.Background(), nil, states, nil)}
			raw, err := json.Marshal(result)
			if err != nil {
				t.Fatal(err)
			}
			if strings.Contains(string(raw), plaintext) || strings.Contains(string(raw), "sk_env_value") {
				t.Fatalf("result leaks a secret: %s", raw)
			}
			if !strings.Contains(string(raw), `"meta":{"secrets":{"api_key":"`+tc.want+`"}}`) {
				t.Fatalf("meta = %s", raw)
			}
		})
	}

	// A form without a password field: no states, no meta key at all.
	item, fsys := secretSettingsItem("fields:\n    token:\n        type: text\n")
	plain, err := compileSetting("acme.unit", item, fsys)
	if err != nil {
		t.Fatal(err)
	}
	if states := secretStates(plain, &secretSettings{}, envCfg); states != nil {
		t.Fatalf("states without a password field = %v", states)
	}
	raw, err := json.Marshal(SettingsResult{Data: withoutSecrets(plain, map[string]any{"token": "t"}), Meta: settingsMeta(context.Background(), nil, nil, nil)})
	if err != nil {
		t.Fatal(err)
	}
	if strings.Contains(string(raw), "meta") {
		t.Fatalf("meta not omitted: %s", raw)
	}
}

// TestSettingsSecretPut checks the D-13 write side without a database: an
// absent key and an empty string keep the stored value (the key never
// reaches Fill), null clears it, a new string replaces it, anything else
// is a 422 on the field before anything is written; a required password
// field is not required on a save; and the states after the fill are what
// the response meta reports.
func TestSettingsSecretPut(t *testing.T) {
	setting := secretTwoFields(t)
	const stored, replaced = "sk_old", "sk_new"
	fill := func(t *testing.T, model *secretSettings, body map[string]any) {
		t.Helper()
		if err := liftSecretValues(setting, body); err != nil {
			t.Fatal(err)
		}
		if err := lagoon.Fill(model, settingWritable(setting), projectSettingBody(setting, body), false); err != nil {
			t.Fatal(err)
		}
	}

	t.Run("absent keeps", func(t *testing.T) {
		model := &secretSettings{APIKey: lagoon.NewEncrypted(stored)}
		fill(t, model, map[string]any{"token": "t"})
		if model.APIKey.Reveal() != stored || model.Token != "t" {
			t.Fatalf("model = %+v", model)
		}
	})
	t.Run("empty string keeps", func(t *testing.T) {
		model := &secretSettings{APIKey: lagoon.NewEncrypted(stored)}
		body := map[string]any{"api_key": "", "token": "t"}
		fill(t, model, body)
		if _, present := body["api_key"]; present {
			t.Fatalf("empty string reached the projection: %#v", body)
		}
		if model.APIKey.Reveal() != stored {
			t.Fatalf("api_key = %q", model.APIKey.Reveal())
		}
	})
	t.Run("null clears", func(t *testing.T) {
		model := &secretSettings{APIKey: lagoon.NewEncrypted(stored)}
		fill(t, model, map[string]any{"api_key": nil})
		if model.APIKey.Reveal() != "" {
			t.Fatalf("api_key = %q, want cleared", model.APIKey.Reveal())
		}
		if got := secretStates(setting, model, nil)["api_key"]; got != SecretEmpty {
			t.Fatalf("state after clear = %s", got)
		}
	})
	t.Run("string replaces", func(t *testing.T) {
		model := &secretSettings{APIKey: lagoon.NewEncrypted(stored)}
		fill(t, model, map[string]any{"api_key": replaced})
		if model.APIKey.Reveal() != replaced {
			t.Fatalf("api_key = %q", model.APIKey.Reveal())
		}
		if got := secretStates(setting, model, nil)["api_key"]; got != SecretStored {
			t.Fatalf("state after replace = %s", got)
		}
	})
	for _, bad := range []any{5, true, []any{"x"}, map[string]any{"v": "x"}} {
		t.Run("non-string is 422", func(t *testing.T) {
			err := liftSecretValues(setting, map[string]any{"api_key": bad})
			var verr *ValidationError
			if !errors.As(err, &verr) {
				t.Fatalf("%#v: err = %v", bad, err)
			}
			if _, ok := verr.Details["api_key"]; !ok || len(verr.Details) != 1 {
				t.Fatalf("details = %#v", verr.Details)
			}
		})
	}
	t.Run("required password is not required on save", func(t *testing.T) {
		item, fsys := secretSettingsItem("fields:\n    api_key:\n        type: password\n        required: true\n    token:\n        type: text\n        required: true\n")
		req, err := compileSetting("acme.unit", item, fsys)
		if err != nil {
			t.Fatal(err)
		}
		err = requireSettingInputs(req, map[string]any{})
		var verr *ValidationError
		if !errors.As(err, &verr) {
			t.Fatalf("err = %v", err)
		}
		if _, ok := verr.Details["api_key"]; ok {
			t.Fatalf("absent password reported required: %#v", verr.Details)
		}
		if _, ok := verr.Details["token"]; !ok {
			t.Fatalf("required text not reported: %#v", verr.Details)
		}
	})
}