package tests

import (
	"context"
	"log/slog"
	"sync/atomic"
	"testing"
	"time"

	"github.com/jfraeys/fetch_ml/internal/logging"
	"github.com/jfraeys/fetch_ml/internal/network"
)

func newTestLogger() *logging.Logger {
	return logging.NewLogger(slog.LevelInfo, false)
}

func TestSSHPool_GetBlocksUntilConnectionReturned(t *testing.T) {
	logger := newTestLogger()
	maxConns := 2
	created := atomic.Int32{}
	p := network.NewSSHPool(maxConns, func() (*network.SSHClient, error) {
		created.Add(1)
		return &network.SSHClient{}, nil
	}, logger)
	t.Cleanup(p.Close)

	ctx := context.Background()
	conn1, err := p.Get(ctx)
	if err != nil {
		t.Fatalf("first Get failed: %v", err)
	}
	conn2, err := p.Get(ctx)
	if err != nil {
		t.Fatalf("second Get failed: %v", err)
	}

	if got := created.Load(); got != int32(maxConns) {
		t.Fatalf("expected %d creations, got %d", maxConns, got)
	}

	blocked := make(chan error, 1)
	go func() {
		conn, err := p.Get(ctx)
		if err == nil && conn != nil {
			p.Put(conn)
		}
		blocked <- err
	}()

	select {
	case err := <-blocked:
		t.Fatalf("expected call to block, got err=%v", err)
	case <-time.After(50 * time.Millisecond):
	}

	p.Put(conn1)

	select {
	case err := <-blocked:
		if err != nil {
			t.Fatalf("blocked Get returned error: %v", err)
		}
	case <-time.After(time.Second):
		t.Fatal("expected blocked Get to proceed after Put")
	}

	p.Put(conn2)
}

func TestSSHPool_GetReturnsContextErrorWhenWaiting(t *testing.T) {
	logger := newTestLogger()
	p := network.NewSSHPool(1, func() (*network.SSHClient, error) {
		return &network.SSHClient{}, nil
	}, logger)
	t.Cleanup(p.Close)

	ctx := context.Background()
	conn, err := p.Get(ctx)
	if err != nil {
		t.Fatalf("initial Get failed: %v", err)
	}

	waitCtx, cancel := context.WithTimeout(context.Background(), 50*time.Millisecond)
	defer cancel()

	_, err = p.Get(waitCtx)
	if err != context.DeadlineExceeded {
		t.Fatalf("expected deadline exceeded, got %v", err)
	}

	p.Put(conn)
}

func TestSSHPool_ReusesReturnedConnections(t *testing.T) {
	logger := newTestLogger()
	p := network.NewSSHPool(1, func() (*network.SSHClient, error) {
		return &network.SSHClient{}, nil
	}, logger)
	t.Cleanup(p.Close)

	ctx := context.Background()
	conn, err := p.Get(ctx)
	if err != nil {
		t.Fatalf("first Get failed: %v", err)
	}

	p.Put(conn)

	conn2, err := p.Get(ctx)
	if err != nil {
		t.Fatalf("second Get failed: %v", err)
	}

	if conn2 != conn {
		t.Fatalf("expected pooled connection reuse, got different pointer")
	}

	p.Put(conn2)
}