package adminapi

import (
	"context"
	"errors"
	"strings"
	"testing"
	"time"

	"gitea.mynodes.xyz/ilker/llmgw/internal/store"
)

type memSettings struct{ versions []store.SettingsVersion }

func (m *memSettings) ClusterSettings(context.Context) (store.SettingsVersion, error) {
	if len(m.versions) == 0 {
		return store.SettingsVersion{}, nil
	}
	return m.versions[len(m.versions)-1], nil
}

func (m *memSettings) ClusterSettingsAt(_ context.Context, v int64) (store.SettingsVersion, error) {
	if v < 1 || int(v) > len(m.versions) {
		return store.SettingsVersion{}, nil
	}
	return m.versions[v-1], nil
}

func (m *memSettings) ClusterSettingsHistory(context.Context, int) ([]store.SettingsVersion, error) {
	var out []store.SettingsVersion
	for i := len(m.versions) - 1; i >= 0; i-- {
		out = append(out, m.versions[i])
	}
	return out, nil
}

func (m *memSettings) PutClusterSettings(_ context.Context, base int64, body, by, note string) (int64, error) {
	if base != int64(len(m.versions)) {
		return 0, store.ErrSettingsChanged
	}
	m.versions = append(m.versions, store.SettingsVersion{Version: base + 1, Body: body, By: by, Note: note, At: time.Now()})
	return base + 1, nil
}

func TestSettingsAreCheckedKeptAndRolledBack(t *testing.T) {
	a, _ := setup(t, testModels())
	st := &memSettings{}
	a.SetSettings(&Settings{Store: st, Check: func(b []byte) error {
		if strings.Contains(string(b), "listen") {
			return errors.New("listen is each machine's")
		}
		return nil
	}})
	var v SettingsView
	if code := call(t, a, "PUT", "/api/v1/settings", `{"base":0,"body":"router:\n  retries: 2\n"}`, &v); code != 200 || v.Version != 1 {
		t.Fatalf("first: %d %+v", code, v)
	}
	if code := call(t, a, "PUT", "/api/v1/settings", `{"base":1,"body":"listen: :1\n"}`, nil); code != 400 {
		t.Errorf("a document the check refuses: %d", code)
	}
	if code := call(t, a, "PUT", "/api/v1/settings", `{"base":0,"body":"router: {}\n"}`, nil); code != 409 {
		t.Errorf("a change from an old version: %d", code)
	}
	if code := call(t, a, "PUT", "/api/v1/settings", `{"base":1,"body":"router:\n  retries: 5\n"}`, nil); code != 200 {
		t.Fatalf("second: %d", code)
	}
	if code := call(t, a, "POST", "/api/v1/settings/rollback", `{"version":1}`, &v); code != 200 ||
		v.Version != 3 || v.Body != "router:\n  retries: 2\n" || v.Note != "back to version 1" {
		t.Errorf("rollback: %d %+v", code, v)
	}
	var h []SettingsView
	if code := call(t, a, "GET", "/api/v1/settings/history", "", &h); code != 200 || len(h) != 3 || h[0].Version != 3 {
		t.Errorf("history: %d %+v", code, h)
	}
	if code := call(t, a, "GET", "/api/v1/settings?version=9", "", nil); code != 404 {
		t.Errorf("a version that is not there: %d", code)
	}
}