package rss

import (
	"errors"
	"fmt"
	"os"
	"path/filepath"
	"strings"
)

var processedItemsDir string

//nolint:gochecknoinits
func init() {
	userHomeDir, err := os.UserHomeDir()
	if err != nil {
		panic("Failed to get user's home directory: " + err.Error())
	}

	processedItemsDir = strings.Replace("~/.rsser", "~", userHomeDir, 1)

	if err := os.MkdirAll(processedItemsDir, 0o755); err != nil {
		panic("Failed to create ~/.rsser: " + err.Error())
	}
}

func (r *RSS) addProcessedItem(domain, guid string) error {
	file, err := os.OpenFile(
		filepath.Join(processedItemsDir, domain),
		os.O_APPEND|os.O_CREATE|os.O_WRONLY,
		0o644,
	)
	if err != nil {
		return fmt.Errorf("add processed item: %w", err)
	}
	defer file.Close()

	if _, err := file.WriteString(guid + "\n"); err != nil {
		return fmt.Errorf("add processed item: %w", err)
	}

	return nil
}

func (r *RSS) checkItemWasProcessed(domain, guid string) (bool, error) {
	fileDataBytes, err := os.ReadFile(filepath.Join(processedItemsDir, domain))
	if err != nil {
		if errors.Is(err, os.ErrNotExist) {
			return false, nil
		}

		return false, fmt.Errorf("check item processing: %w", err)
	}

	fileData := string(fileDataBytes)

	for line := range strings.Lines(fileData) {
		if line == guid+"\n" {
			return true, nil
		}
	}

	return false, nil
}