package web

import (
	"fmt"
	"net/http"
	"os"
	"path/filepath"
	"time"
)

func (s *Server) handleExportPage(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "text/html; charset=utf-8")
	if err := exportPage.ExecuteTemplate(w, "base", nil); err != nil {
		s.serverError(w, "render export page", err)
	}
}

func (s *Server) handleExportDB(w http.ResponseWriter, r *http.Request) {
	includeBlobs := r.URL.Query().Get("blobs") != "false" // default: include

	// Snapshot to a fresh temp path (VACUUM INTO requires the file not exist).
	tmpDir, err := os.MkdirTemp("", "hsa-export-")
	if err != nil {
		s.serverError(w, "export tempdir", err)
		return
	}
	defer os.RemoveAll(tmpDir)
	snapPath := filepath.Join(tmpDir, "snapshot.db")

	if err := s.store.SnapshotTo(snapPath, includeBlobs); err != nil {
		s.serverError(w, "export snapshot", err)
		return
	}

	f, err := os.Open(snapPath)
	if err != nil {
		s.serverError(w, "open snapshot", err)
		return
	}
	defer f.Close()

	suffix := ""
	if !includeBlobs {
		suffix = "-metadata"
	}
	filename := fmt.Sprintf("hsa-export-%s%s.db", time.Now().Format(dateLayout), suffix)

	w.Header().Set("Content-Type", "application/octet-stream")
	w.Header().Set("Content-Disposition", fmt.Sprintf("attachment; filename=%q", filename))
	if fi, err := f.Stat(); err == nil {
		w.Header().Set("Content-Length", fmt.Sprintf("%d", fi.Size()))
	}
	http.ServeContent(w, r, filename, time.Now(), f)
}