package main

import (
	"bytes"
	"context"
	"encoding/json"
	"os"
	"path/filepath"
	"testing"
	"time"

	"proxy-pool/internal/loadgen"
)

func TestExecutePassesBoundedWorkloadAndWritesJSON(t *testing.T) {
	var received loadgen.Options
	var stdout, stderr bytes.Buffer
	code := execute(context.Background(), []string{
		"-target", "https://target.example/path", "-proxy", "http://gateway.example:8080", "-method", "post",
		"-requests", "3", "-concurrency", "2", "-timeout", "2s", "-header", "X-Run: fixed", "-body", `{"count":1}`,
	}, func(_ context.Context, options loadgen.Options) (loadgen.Report, error) {
		received = options
		return loadgen.Report{
			Requests: 3, Completed: 3, Succeeded: 3, Duration: time.Second,
			RateStartsGenerated: 3, RateStartsDropped: 1,
		}, nil
	}, &stdout, &stderr)
	if code != 0 || received.TargetURL != "https://target.example/path" || received.ProxyURL != "http://gateway.example:8080" ||
		received.Method != "post" || received.Requests != 3 || received.Duration != 0 || received.Concurrency != 2 ||
		received.Headers.Get("X-Run") != "fixed" || string(received.RequestBody) != `{"count":1}` || stderr.Len() != 0 {
		t.Fatalf("execute() = %d; options=%+v stderr=%q", code, received, stderr.String())
	}
	var report loadgen.Report
	if err := json.Unmarshal(stdout.Bytes(), &report); err != nil || report.Succeeded != 3 ||
		report.RateStartsGenerated != 3 || report.RateStartsDropped != 1 {
		t.Fatalf("JSON report = (%+v, %v)", report, err)
	}
}

func TestExecuteRejectsInvalidWorkload(t *testing.T) {
	var stdout, stderr bytes.Buffer
	code := execute(context.Background(), []string{"-target", "http://target.example"}, loadgen.Run, &stdout, &stderr)
	if code != 2 || stdout.Len() != 0 || stderr.Len() == 0 {
		t.Fatalf("execute() = %d stdout=%q stderr=%q", code, stdout.String(), stderr.String())
	}
}

func TestExecutePassesCONNECTScenario(t *testing.T) {
	var received loadgen.Options
	var stdout, stderr bytes.Buffer
	code := execute(context.Background(), []string{
		"-scenario", "connect", "-target", "https://target.example/health", "-proxy", "http://gateway.example:8080",
		"-requests", "2", "-concurrency", "1", "-timeout", "2s", "-hold", "30s",
	}, func(_ context.Context, options loadgen.Options) (loadgen.Report, error) {
		received = options
		return loadgen.Report{Requests: 2, Completed: 2, Succeeded: 2, Duration: time.Second}, nil
	}, &stdout, &stderr)
	if code != 0 || received.Scenario != loadgen.ScenarioConnect || received.TunnelHold != 30*time.Second ||
		received.ProxyURL != "http://gateway.example:8080" || stderr.Len() != 0 {
		t.Fatalf("execute() = %d; options=%+v stderr=%q", code, received, stderr.String())
	}
}

func TestExecutePassesExtractScenario(t *testing.T) {
	var received loadgen.Options
	var stdout, stderr bytes.Buffer
	code := execute(context.Background(), []string{
		"-scenario", "extract", "-target", "http://controller.example:8081/api/v1/proxies/extract",
		"-requests", "2", "-concurrency", "1", "-timeout", "2s", "-extract-count", "3", "-extract-fulfillment", "allOrNothing",
	}, func(_ context.Context, options loadgen.Options) (loadgen.Report, error) {
		received = options
		return loadgen.Report{Requests: 2, Completed: 2, Succeeded: 2, Duration: time.Second}, nil
	}, &stdout, &stderr)
	if code != 0 || received.Scenario != loadgen.ScenarioExtract || received.Method != "" || received.ExtractCount != 3 ||
		received.ExtractFulfillment != "allOrNothing" || stderr.Len() != 0 {
		t.Fatalf("execute() = %d; options=%+v stderr=%q", code, received, stderr.String())
	}
}

func TestExecuteWritesReportFile(t *testing.T) {
	t.Parallel()

	path := filepath.Join(t.TempDir(), "load-report.json")
	if err := os.WriteFile(path, []byte("incomplete"), 0o600); err != nil {
		t.Fatalf("WriteFile(): %v", err)
	}
	var stdout, stderr bytes.Buffer
	code := execute(context.Background(), []string{
		"-target", "https://target.example/health", "-requests", "1", "-concurrency", "1", "-output", path,
	}, func(_ context.Context, _ loadgen.Options) (loadgen.Report, error) {
		return loadgen.Report{Requests: 1, Completed: 1, Succeeded: 1, Duration: time.Second}, nil
	}, &stdout, &stderr)
	if code != 0 || stderr.Len() != 0 {
		t.Fatalf("execute() = %d, stderr=%q", code, stderr.String())
	}
	content, err := os.ReadFile(path)
	if err != nil {
		t.Fatalf("ReadFile(): %v", err)
	}
	var report loadgen.Report
	if err := json.Unmarshal(content, &report); err != nil || report.Succeeded != 1 || string(content) == "incomplete" {
		t.Fatalf("report file = (%q, %+v, %v)", content, report, err)
	}
}