factor/basis/help/markup/markup.factor

! Copyright (C) 2005, 2009 Slava Pestov.
! See http://factorcode.org/license.txt for BSD license.
USING: accessors arrays definitions generic io kernel assocs
hashtables namespaces make parser prettyprint sequences strings
io.styles vectors words math sorting splitting classes slots fry
sets vocabs help.stylesheet help.topics vocabs.loader quotations
combinators call see ;
IN: help.markup

PREDICATE: simple-element < array
    [ t ] [ first word? not ] if-empty ;

SYMBOL: last-element
SYMBOL: span
SYMBOL: block

: last-span? ( -- ? ) last-element get span eq? ;
: last-block? ( -- ? ) last-element get block eq? ;

: ($span) ( quot -- )
    last-block? [ nl ] when
    span last-element set
    call ; inline

GENERIC: print-element ( element -- )

M: simple-element print-element [ print-element ] each ;
M: string print-element [ write ] ($span) ;
M: array print-element unclip execute( arg -- ) ;
M: word print-element { } swap execute( arg -- ) ;
M: f print-element drop ;

: print-element* ( element style -- )
    [ print-element ] with-style ;

: with-default-style ( quot -- )
    default-span-style get [
        last-element off
        default-block-style get swap with-nesting
    ] with-style ; inline

: print-content ( element -- )
    [ print-element ] with-default-style ;

: ($block) ( quot -- )
    last-element get [ nl ] when
    span last-element set
    call
    block last-element set ; inline

! Some spans

: $snippet ( children -- )
    [ snippet-style get print-element* ] ($span) ;

! for help-lint
ALIAS: $slot $snippet

: $emphasis ( children -- )
    [ emphasis-style get print-element* ] ($span) ;

: $strong ( children -- )
    [ strong-style get print-element* ] ($span) ;

: $url ( children -- )
    [
        dup first href associate url-style get assoc-union
        print-element*
    ] ($span) ;

: $nl ( children -- )
    nl nl drop ;

! Some blocks
: ($heading) ( children quot -- )
    last-element get [ nl ] when ($block) ; inline

: $heading ( element -- )
    [ heading-style get print-element* ] ($heading) ;

: $subheading ( element -- )
    [ strong-style get print-element* ] ($heading) ;

: ($code-style) ( presentation -- hash )
    presented associate code-style get assoc-union ;

: ($code) ( presentation quot -- )
    [
        snippet-style get [
            last-element off
            [ ($code-style) ] dip with-nesting
        ] with-style
    ] ($block) ; inline

: $code ( element -- )
    "\n" join dup <input> [ write ] ($code) ;

: $syntax ( element -- ) "Syntax" $heading $code ;

: $description ( element -- )
    "Word description" $heading print-element ;

: $class-description ( element -- )
    "Class description" $heading print-element ;

: $error-description ( element -- )
    "Error description" $heading print-element ;

: $var-description ( element -- )
    "Variable description" $heading print-element ;

: $contract ( element -- )
    "Generic word contract" $heading print-element ;

: $examples ( element -- )
    "Examples" $heading print-element ;

: $example ( element -- )
    1 cut* swap "\n" join dup <input> [
        input-style get format nl print-element
    ] ($code) ;

: $unchecked-example ( element -- )
    #! help-lint ignores these.
    $example ;

: $markup-example ( element -- )
    first dup unparse " print-element" append 1array $code
    print-element ;

: $warning ( element -- )
    [
        warning-style get [
            last-element off
            "Warning" $heading print-element
        ] with-nesting
    ] ($heading) ;

! Images
: $image ( element -- )
    [ [ "" ] dip first image associate format ] ($span) ;

! Some links
: write-link ( string object -- )
    link-style get [ write-object ] with-style ;

: ($link) ( article -- )
    [ [ article-name ] [ >link ] bi write-link ] ($span) ;

: $link ( element -- )
    first ($link) ;

: ($definition-link) ( word -- )
    [ article-name ] keep write-link ;

: $definition-link ( element -- )
    first ($definition-link) ;

: ($long-link) ( object -- )
    [ article-title ] [ >link ] bi write-link ;

: $long-link ( object -- )
    first ($long-link) ;

: ($subsection) ( element quot -- )
    [
        subsection-style get [
            bullet get write bl
            call
        ] with-style
    ] ($block) ; inline

: $subsection ( element -- )
    [ first ($long-link) ] ($subsection) ;

: ($vocab-link) ( text vocab -- )
    >vocab-link write-link ;

: $vocab-subsection ( element -- )
    [
        first2 dup vocab-help dup [
            2nip ($long-link)
        ] [
            drop ($vocab-link)
        ] if
    ] ($subsection) ;

: $vocab-link ( element -- )
    first dup vocab-name swap ($vocab-link) ;

: $vocabulary ( element -- )
    first vocabulary>> [
        "Vocabulary" $heading nl dup ($vocab-link)
    ] when* ;

: textual-list ( seq quot -- )
    [ ", " print-element ] swap interleave ; inline

: $links ( topics -- )
    [ [ ($link) ] textual-list ] ($span) ;

: $vocab-links ( vocabs -- )
    [ vocab ] map $links ;

: $see-also ( topics -- )
    "See also" $heading $links ;

: related-words ( seq -- )
    dup '[ _ "related" set-word-prop ] each ;

: $related ( element -- )
    first dup "related" word-prop remove
    [ $see-also ] unless-empty ;

: ($grid) ( style quot -- )
    [
        table-content-style get [
            swap [ last-element off call ] tabular-output
        ] with-style
    ] ($block) ; inline

: $list ( element -- )
    list-style get [
        [
            [
                bullet get write-cell
                [ print-element ] with-cell
            ] with-row
        ] each
    ] ($grid) ;

: $table ( element -- )
    table-style get [
        [
            [
                [ [ print-element ] with-cell ] each
            ] with-row
        ] each
    ] ($grid) ;

: a/an ( str -- str )
    [ first ] [ length ] bi 1 =
    "afhilmnorsx" "aeiou" ? member? "an" "a" ? ;

GENERIC: ($instance) ( element -- )

M: word ($instance)
    dup name>> a/an write bl ($link) ;

M: string ($instance)
    dup a/an write bl $snippet ;

M: f ($instance)
    drop { f } $link ;

: $instance ( element -- ) first ($instance) ;

: $or ( element -- )
    dup length {
        { 1 [ first ($instance) ] }
        { 2 [ first2 [ ($instance) " or " print-element ] [ ($instance) ] bi* ] }
        [
            drop
            unclip-last
            [ [ ($instance) ", " print-element ] each ]
            [ "or " print-element ($instance) ]
            bi*
        ]
    } case ;

: $maybe ( element -- )
    f suffix $or ;

: $quotation ( element -- )
    { "a " { $link quotation } " with stack effect " } print-element
    $snippet ;

: values-row ( seq -- seq )
    unclip \ $snippet swap ?word-name 2array
    swap dup first word? [ \ $instance prefix ] when 2array ;

: $values ( element -- )
    "Inputs and outputs" $heading
    [ values-row ] map $table ;

: $side-effects ( element -- )
    "Side effects" $heading "Modifies " print-element
    [ $snippet ] textual-list ;

: $errors ( element -- )
    "Errors" $heading print-element ;

: $notes ( element -- )
    "Notes" $heading print-element ;

: ($see) ( word quot -- )
    [
        snippet-style get [
            code-style get swap with-nesting
        ] with-style
    ] ($block) ; inline

: $see ( element -- ) first [ see* ] ($see) ;

: $synopsis ( element -- ) first [ synopsis write ] ($see) ;

: $definition ( element -- )
    "Definition" $heading $see ;

: $methods ( element -- )
    first methods [
        "Methods" $heading
        [ see-all ] ($see)
    ] unless-empty ;

: $value ( object -- )
    "Variable value" $heading
    "Current value in global namespace:" print-element
    first dup [ pprint-short ] ($code) ;

: $curious ( element -- )
    "For the curious..." $heading print-element ;

: $references ( element -- )
    "References" $heading
    unclip print-element [ \ $link swap ] { } map>assoc $list ;

: $shuffle ( element -- )
    drop
    "Shuffle word. Re-arranges the stack according to the stack effect pattern." $description ;

: $low-level-note ( children -- )
    drop
    "Calling this word directly is not necessary in most cases. Higher-level words call it automatically." $notes ;

: $values-x/y ( children -- )
    drop { { "x" number } { "y" number } } $values ;

: $parsing-note ( children -- )
    drop
    "This word should only be called from parsing words."
    $notes ;

: $io-error ( children -- )
    drop
    "Throws an error if the I/O operation fails." $errors ;

FROM: prettyprint.private => with-pprint ;

: $prettyprinting-note ( children -- )
    drop {
        "This word should only be called from inside the "
        { $link with-pprint } " combinator."
    } $notes ;

GENERIC: elements* ( elt-type element -- )

M: simple-element elements*
    [ elements* ] with each ;

M: object elements* 2drop ;

M: array elements*
    [ [ elements* ] with each ] 2keep
    [ first eq? ] keep swap [ , ] [ drop ] if ;

: elements ( elt-type element -- seq ) [ elements* ] { } make ;

: collect-elements ( element seq -- elements )
    swap '[ _ elements [ rest ] map concat ] map concat prune ;

: <$link> ( topic -- element )
    1array \ $link prefix ;

: <$snippet> ( str -- element )
    1array \ $snippet prefix ;