package cmd

import (
	"fmt"
	"os"
	"sort"

	"github.com/spf13/cobra"
	"github.com/yeho/doks/internal/registry"
)

var listTagFilter string

var listCmd = &cobra.Command{
	Use:   "list",
	Short: "List all registered documents",
	Long:  `Display all documents registered in doks, optionally filtered by tag.`,
	Run: func(cmd *cobra.Command, args []string) {
		reg, err := registry.Load(cfg.RegistryPath())
		if err != nil {
			fmt.Fprintf(os.Stderr, "Error loading registry: %v\n", err)
			os.Exit(1)
		}

		entries := reg.List()
		if len(entries) == 0 {
			fmt.Println("No documents registered")
			return
		}

		// Sort by key
		sort.Slice(entries, func(i, j int) bool {
			return entries[i].Key < entries[j].Key
		})

		// Filter by tag if specified
		if listTagFilter != "" {
			filtered := make([]*registry.Entry, 0)
			for _, entry := range entries {
				if hasTag(entry.Tags, listTagFilter) {
					filtered = append(filtered, entry)
				}
			}
			entries = filtered
		}

		if len(entries) == 0 {
			fmt.Printf("No documents found with tag '%s'\n", listTagFilter)
			return
		}

		// Print entries
		for _, entry := range entries {
			symlink := ""
			if entry.HasSymlink {
				symlink = " [symlinked]"
			}
			tags := ""
			if len(entry.Tags) > 0 {
				tags = fmt.Sprintf(" [%s]", joinStrings(entry.Tags, ", "))
			}
			fmt.Printf("  %s%s%s\n", entry.Key, tags, symlink)
			if entry.Description != "" {
				fmt.Printf("    %s\n", entry.Description)
			}
		}
	},
}

func init() {
	rootCmd.AddCommand(listCmd)
	listCmd.Flags().StringVarP(&listTagFilter, "tag", "t", "", "Filter by tag")
}

func hasTag(tags []string, target string) bool {
	for _, tag := range tags {
		if tag == target {
			return true
		}
	}
	return false
}

func joinStrings(strs []string, sep string) string {
	if len(strs) == 0 {
		return ""
	}
	result := strs[0]
	for i := 1; i < len(strs); i++ {
		result += sep + strs[i]
	}
	return result
}