//go:build linux || freebsd
// +build linux freebsd

package file

import (
	"bytes"
	"context"
	"net/url"
	"os"
	"path/filepath"
	"testing"

	"codeberg.org/petrbalvin/goget/internal/core"
)

func TestDownloadFile(t *testing.T) {
	tmp := t.TempDir()
	src := filepath.Join(tmp, "src.txt")
	dst := filepath.Join(tmp, "dst.txt")
	os.WriteFile(src, []byte("hello world"), 0644)

	proto := NewProtocol()
	u := &url.URL{Scheme: "file", Path: src}
	result, err := proto.Download(context.Background(), &core.DownloadRequest{
		URL:    u,
		Output: dst,
	})
	if err != nil {
		t.Fatal(err)
	}
	if result.BytesDownloaded != 11 {
		t.Errorf("bytes = %d, want 11", result.BytesDownloaded)
	}
	data, _ := os.ReadFile(dst)
	if string(data) != "hello world" {
		t.Errorf("content = %q, want %q", data, "hello world")
	}
}

func TestDownloadFileToWriter(t *testing.T) {
	tmp := t.TempDir()
	src := filepath.Join(tmp, "src.txt")
	os.WriteFile(src, []byte("test"), 0644)

	var buf bytes.Buffer
	proto := NewProtocol()
	u := &url.URL{Scheme: "file", Path: src}
	_, err := proto.Download(context.Background(), &core.DownloadRequest{
		URL:    u,
		Output: "-",
		Writer: &buf,
	})
	if err != nil {
		t.Fatal(err)
	}
	if buf.String() != "test" {
		t.Errorf("content = %q, want %q", buf.String(), "test")
	}
}

func TestDownloadFileNotFound(t *testing.T) {
	proto := NewProtocol()
	u := &url.URL{Scheme: "file", Path: "/nonexistent/path"}
	_, err := proto.Download(context.Background(), &core.DownloadRequest{
		URL:    u,
		Output: "/tmp/out",
	})
	if err == nil {
		t.Error("expected error for nonexistent file")
	}
}

func TestDownloadDirectory(t *testing.T) {
	tmp := t.TempDir()
	srcDir := filepath.Join(tmp, "srcdir")
	dstDir := filepath.Join(tmp, "dstdir")
	os.MkdirAll(filepath.Join(srcDir, "sub"), 0755)
	os.WriteFile(filepath.Join(srcDir, "a.txt"), []byte("a"), 0644)
	os.WriteFile(filepath.Join(srcDir, "sub/b.txt"), []byte("b"), 0644)

	proto := NewProtocol()
	u := &url.URL{Scheme: "file", Path: srcDir}
	result, err := proto.Download(context.Background(), &core.DownloadRequest{
		URL:    u,
		Output: dstDir,
	})
	if err != nil {
		t.Fatal(err)
	}
	if result.ChunksCount != 2 {
		t.Errorf("files = %d, want 2", result.ChunksCount)
	}
	if result.BytesDownloaded != 2 {
		t.Errorf("bytes = %d, want 2", result.BytesDownloaded)
	}
	// Verify files exist
	if _, err := os.Stat(filepath.Join(dstDir, "a.txt")); err != nil {
		t.Error("a.txt not found")
	}
	if _, err := os.Stat(filepath.Join(dstDir, "sub", "b.txt")); err != nil {
		t.Error("sub/b.txt not found")
	}
}

func TestResumeFile(t *testing.T) {
	tmp := t.TempDir()
	src := filepath.Join(tmp, "src.txt")
	dst := filepath.Join(tmp, "dst.txt")
	os.WriteFile(src, []byte("hello world"), 0644)
	os.WriteFile(dst, []byte("hello"), 0644) // partial: 5 bytes

	proto := NewProtocol()
	u := &url.URL{Scheme: "file", Path: src}
	result, err := proto.Download(context.Background(), &core.DownloadRequest{
		URL:    u,
		Output: dst,
		Resume: true,
	})
	if err != nil {
		t.Fatal(err)
	}
	if !result.Resumed {
		t.Error("expected Resumed=true")
	}
	if result.BytesDownloaded != 11 {
		t.Errorf("bytes = %d, want 11", result.BytesDownloaded)
	}
}