package cmd

import (
	"fmt"
	"io"
	"mime"
	"os"
	"path/filepath"

	"github.com/kb-search/kb/internal/api"
	"github.com/spf13/cobra"
)

var exportCmd = &cobra.Command{
	Use:   "export <id>",
	Short: "Download original document file",
	Args:  cobra.ExactArgs(1),
	RunE:  runExport,
}

func init() {
	exportCmd.Flags().StringP("output", "o", "", "output file path (default: original filename to current directory)")
	rootCmd.AddCommand(exportCmd)
}

func runExport(cmd *cobra.Command, args []string) error {
	client := api.NewClient()
	resp, err := client.Get("/api/v1/documents/" + args[0] + "/file")
	if err != nil {
		fmt.Fprintln(os.Stderr, err)
		os.Exit(1)
	}
	if err := api.CheckError(resp); err != nil {
		fmt.Fprintln(os.Stderr, err)
		os.Exit(1)
	}
	defer resp.Body.Close()

	outPath, _ := cmd.Flags().GetString("output")

	if outPath == "" {
		// Try to get filename from Content-Disposition header
		cd := resp.Header.Get("Content-Disposition")
		if cd != "" {
			_, params, err := mime.ParseMediaType(cd)
			if err == nil && params["filename"] != "" {
				outPath = params["filename"]
			}
		}
		if outPath == "" {
			outPath = "document-" + args[0]
		}
	}

	if outPath == "-" {
		_, err := io.Copy(os.Stdout, resp.Body)
		return err
	}

	outPath = filepath.Clean(outPath)
	f, err := os.Create(outPath)
	if err != nil {
		return fmt.Errorf("failed to create output file: %w", err)
	}
	defer f.Close()

	n, err := io.Copy(f, resp.Body)
	if err != nil {
		return fmt.Errorf("failed to write file: %w", err)
	}

	fmt.Fprintf(os.Stderr, "Saved %s (%d bytes)\n", outPath, n)
	return nil
}