package cc

import (
	"context"
	"errors"
	"testing"
)

func withRunner(fn func(ctx context.Context, cwd string, args []string) ([]byte, []byte, error)) func() {
	orig := RunClaude
	RunClaude = fn
	return func() { RunClaude = orig }
}

func TestSpawnClaude_CleanJSON(t *testing.T) {
	restore := withRunner(func(_ context.Context, _ string, _ []string) ([]byte, []byte, error) {
		return []byte(`{"result":"ok","session_id":"abc123"}`), nil, nil
	})
	defer restore()

	res, err := SpawnClaude(context.Background(), Opts{Prompt: "hello"})
	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if res.SessionID != "abc123" {
		t.Errorf("SessionID = %q, want abc123", res.SessionID)
	}
	if res.ResultText != "ok" {
		t.Errorf("ResultText = %q, want ok", res.ResultText)
	}
}

func TestSpawnClaude_NDJSONTail(t *testing.T) {
	ndjson := `{"type":"progress","data":"thinking"}
{"type":"progress","data":"still thinking"}
{"result":"done","session_id":"sess99"}`

	restore := withRunner(func(_ context.Context, _ string, _ []string) ([]byte, []byte, error) {
		return []byte(ndjson), nil, nil
	})
	defer restore()

	res, err := SpawnClaude(context.Background(), Opts{Prompt: "go"})
	if err != nil {
		t.Fatalf("unexpected error: %v", err)
	}
	if res.SessionID != "sess99" {
		t.Errorf("SessionID = %q, want sess99", res.SessionID)
	}
	if res.ResultText != "done" {
		t.Errorf("ResultText = %q, want done", res.ResultText)
	}
}

func TestSpawnClaude_NonZeroExit(t *testing.T) {
	restore := withRunner(func(_ context.Context, _ string, _ []string) ([]byte, []byte, error) {
		return nil, []byte("something went wrong"), errors.New("exit status 1")
	})
	defer restore()

	_, err := SpawnClaude(context.Background(), Opts{Prompt: "hi"})
	if err == nil {
		t.Fatal("expected error, got nil")
	}
	var ce *ClaudeError
	if !errors.As(err, &ce) {
		t.Errorf("expected ClaudeError, got %T: %v", err, err)
	}
}

func TestSpawnClaude_Timeout(t *testing.T) {
	restore := withRunner(func(ctx context.Context, _ string, _ []string) ([]byte, []byte, error) {
		// Respect context cancellation — as the real runner would.
		<-ctx.Done()
		return nil, nil, ctx.Err()
	})
	defer restore()

	_, err := SpawnClaude(context.Background(), Opts{Prompt: "slow", TimeoutMs: 1})
	if err == nil {
		t.Fatal("expected timeout error, got nil")
	}
	var te *ClaudeTimeoutError
	if !errors.As(err, &te) {
		t.Errorf("expected ClaudeTimeoutError, got %T: %v", err, err)
	}
}