package tokens

import (
	"context"
	"errors"
	"sync/atomic"
	"testing"
	"time"

	"git.hangman-lab.top/hzhang/Plexum-fabric-channel-plugin/internal/fabric"
)

func fakeSession(guildNodes ...string) *fabric.Session {
	s := &fabric.Session{User: fabric.SessionUser{ID: "u1", Email: "u@x"}}
	for _, g := range guildNodes {
		s.Guilds = append(s.Guilds, fabric.GuildInfo{NodeID: g, Endpoint: "http://" + g})
		s.GuildAccessTokens = append(s.GuildAccessTokens, fabric.GuildAccessToken{
			GuildNodeID: g, Token: "tok-" + g,
		})
	}
	return s
}

func TestGetFirstLogsIn(t *testing.T) {
	var calls atomic.Int32
	c := New(0, func(context.Context, string) (*fabric.Session, error) {
		calls.Add(1)
		return fakeSession("g1"), nil
	})
	s, err := c.Get(context.Background(), "alice")
	if err != nil || s.User.ID != "u1" {
		t.Fatalf("get err=%v", err)
	}
	if calls.Load() != 1 {
		t.Errorf("calls = %d", calls.Load())
	}
}

func TestGetWithinTTLReusesCached(t *testing.T) {
	var calls atomic.Int32
	c := New(time.Minute, func(context.Context, string) (*fabric.Session, error) {
		calls.Add(1)
		return fakeSession("g1"), nil
	})
	c.Get(context.Background(), "alice")
	c.Get(context.Background(), "alice")
	c.Get(context.Background(), "alice")
	if calls.Load() != 1 {
		t.Errorf("calls = %d (TTL fresh)", calls.Load())
	}
}

func TestGetAfterTTLReLogs(t *testing.T) {
	var calls atomic.Int32
	c := New(10*time.Millisecond, func(context.Context, string) (*fabric.Session, error) {
		calls.Add(1)
		return fakeSession("g1"), nil
	})
	c.Get(context.Background(), "alice")
	time.Sleep(20 * time.Millisecond)
	c.Get(context.Background(), "alice")
	if calls.Load() != 2 {
		t.Errorf("calls = %d, want 2 after TTL expiry", calls.Load())
	}
}

func TestInvalidateForcesReLogin(t *testing.T) {
	var calls atomic.Int32
	c := New(time.Minute, func(context.Context, string) (*fabric.Session, error) {
		calls.Add(1)
		return fakeSession("g1"), nil
	})
	c.Get(context.Background(), "alice")
	c.Invalidate("alice")
	c.Get(context.Background(), "alice")
	if calls.Load() != 2 {
		t.Errorf("calls = %d, want 2 after Invalidate", calls.Load())
	}
}

func TestLoginErrorBubbles(t *testing.T) {
	sentinel := errors.New("boom")
	c := New(0, func(context.Context, string) (*fabric.Session, error) {
		return nil, sentinel
	})
	_, err := c.Get(context.Background(), "alice")
	if !errors.Is(err, sentinel) {
		t.Errorf("err = %v", err)
	}
}

func TestGuildTokenHappy(t *testing.T) {
	c := New(time.Minute, func(context.Context, string) (*fabric.Session, error) {
		return fakeSession("g1", "g2"), nil
	})
	tok, err := c.GuildToken(context.Background(), "alice", "g2")
	if err != nil || tok != "tok-g2" {
		t.Errorf("token=%q err=%v", tok, err)
	}
}

func TestGuildTokenMissingGuildRetriesThenErrors(t *testing.T) {
	var calls atomic.Int32
	c := New(time.Minute, func(context.Context, string) (*fabric.Session, error) {
		calls.Add(1)
		return fakeSession("g1"), nil
	})
	_, err := c.GuildToken(context.Background(), "alice", "missing")
	if err == nil {
		t.Fatal("expected error")
	}
	// First Get + post-invalidate Get = 2 logins
	if calls.Load() != 2 {
		t.Errorf("calls = %d, want 2 (initial + retry)", calls.Load())
	}
}

func TestPeekDoesNotLogin(t *testing.T) {
	var calls atomic.Int32
	c := New(time.Minute, func(context.Context, string) (*fabric.Session, error) {
		calls.Add(1)
		return fakeSession("g1"), nil
	})
	if c.Peek("alice") != nil {
		t.Errorf("Peek on empty should be nil")
	}
	if calls.Load() != 0 {
		t.Errorf("Peek should not call Login")
	}
}