package cmd

import (
	"io"
	"text/template"

	"go.fifitido.net/cmd/opt"
)

func WriteBashCompletions(out io.Writer, rootCmd *Command) error {
	return bashTpl.Execute(out, map[string]any{
		"RootCmd":    rootCmd,
		"GlobalOpts": opt.Globals(),
	})
}

var bashTpl = template.Must(template.New("bash").Funcs(tplFuncs).Parse(`
{{- $rootCmd := .RootCmd -}}
{{- $progName := $rootCmd.Name -}}
{{- $varName := under $rootCmd.Name -}}

{{- define "cmd" }}
  {{ $currIdx := .Index }}
  {{ $nextIdx := inc .Index }}
  "{{ .Cmd.Name }}")
	case ${COMP_WORDS[{{ $currIdx }}]} in
		{{ range .Cmd.Subcommands -}}
		{{ template "cmd" (map "Cmd" . "Index" $nextIdx) -}}
		{{ end }}
		*)
			COMPREPLY=($(compgen -W "{{ join .Cmd.Subcommands.Names " " }} {{ join .Cmd.Opts.Names " "  }}" -- $curr))
	esac
  ;;
{{ end -}}

_{{$varName}}_completions()
{
	local curr prev
	COMPREPLY=()
	curr=${COMP_WORDS[COMP_CWORD]}
	prev=${COMP_WORDS[COMP_CWORD-1]}

    case ${COMP_WORDS[1]} in
		{{ range .RootCmd.Subcommands -}}
		{{ template "cmd" (map "Cmd" . "Index" 2) -}}
		{{ end }}

		*)
		    COMPREPLY=($(compgen -W "{{ join .RootCmd.Subcommands.Names " " }} {{ join .RootCmd.Opts.Names " "  }}" -- $curr))
	esac
}

complete -F _{{$varName}}_completions {{$progName}}
`))