package cmd

import (
	"path/filepath"

	"github.com/spf13/cobra"
	"github.com/warrenronsiek/ctask/internal/config"
	"github.com/warrenronsiek/ctask/internal/workspace"
)

// completionFilter selects which workspaces a command's tab-completion should
// surface. It does not affect lookup — that's still the resolver's job — only
// what the user sees as candidates while typing.
type completionFilter int

const (
	completionActive completionFilter = iota
	completionArchived
	completionAny
)

// completeWorkspaces returns a Cobra ValidArgsFunction that enumerates
// workspace directory basenames matching the requested filter. Basenames are
// emitted (not bare slugs) because the resolver's exact-match step accepts
// basenames unambiguously, while bare slugs can collide across categories or
// dates.
//
// On any internal error we surface ShellCompDirectiveError so the shell shows
// nothing rather than a partial / misleading list.
func completeWorkspaces(filter completionFilter) func(*cobra.Command, []string, string) ([]string, cobra.ShellCompDirective) {
	return func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
		// Only the first positional argument is a workspace name.
		if len(args) > 0 {
			return nil, cobra.ShellCompDirectiveNoFileComp
		}

		roots := config.SearchRoots()
		results, err := workspace.ListWorkspaces(roots, workspace.ListOpts{
			IncludeArchived: filter != completionActive,
		})
		if err != nil {
			return nil, cobra.ShellCompDirectiveError
		}

		var names []string
		for _, ws := range results {
			switch filter {
			case completionActive:
				if ws.Meta.Status == "archived" {
					continue
				}
			case completionArchived:
				if ws.Meta.Status != "archived" {
					continue
				}
			case completionAny:
				// no filter
			}
			names = append(names, filepath.Base(ws.Path))
		}
		return names, cobra.ShellCompDirectiveNoFileComp
	}
}