use builtin;
use str;

set edit:completion:arg-completer[fmerge] = {|@words|
    fn spaces {|n|
        builtin:repeat $n ' ' | str:join ''
    }
    fn cand {|text desc|
        edit:complex-candidate $text &display=$text' '(spaces (- 14 (wcswidth $text)))$desc
    }
    var command = 'fmerge'
    for word $words[1..-1] {
        if (str:has-prefix $word '-') {
            break
        }
        set command = $command';'$word
    }
    var completions = [
        &'fmerge'= {
            cand -e 'enables experimental features'
            cand --experimental 'enables experimental features'
            cand -h 'Print help'
            cand --help 'Print help'
            cand -V 'Print version'
            cand --version 'Print version'
            cand man 'Renders the manual.'
            cand autocomplete 'Renders shell completion scripts.'
            cand merge 'Merge.'
            cand help 'Print this message or the help of the given subcommand(s)'
        }
        &'fmerge;man'= {
            cand -o 'o'
            cand --out 'out'
            cand -f 'f'
            cand --format 'format'
            cand -h 'Print help'
            cand --help 'Print help'
            cand -V 'Print version'
            cand --version 'Print version'
        }
        &'fmerge;autocomplete'= {
            cand -o 'o'
            cand --out 'out'
            cand -s 's'
            cand --shell 'shell'
            cand -h 'Print help'
            cand --help 'Print help'
            cand -V 'Print version'
            cand --version 'Print version'
        }
        &'fmerge;merge'= {
            cand -f 'f'
            cand --file 'file'
            cand -r 'r'
            cand --regex 'regex'
            cand -h 'Print help'
            cand --help 'Print help'
            cand -V 'Print version'
            cand --version 'Print version'
        }
        &'fmerge;help'= {
            cand man 'Renders the manual.'
            cand autocomplete 'Renders shell completion scripts.'
            cand merge 'Merge.'
            cand help 'Print this message or the help of the given subcommand(s)'
        }
        &'fmerge;help;man'= {
        }
        &'fmerge;help;autocomplete'= {
        }
        &'fmerge;help;merge'= {
        }
        &'fmerge;help;help'= {
        }
    ]
    $completions[$command]
}