|
sourcecode:
|
module HTML.LaTeX
( showLatexExps, showLatexExp, showLatexDoc, showLatexDocs
, showLatexDocsWithPackages, showLatexDocWithPackages
, germanLatexDoc, htmlSpecialChars2tex
) where
import Data.List ( intercalate )
import HTML.Base
--- Transforms HTML expressions into LaTeX string representation.
showLatexExps :: [BaseHtml] -> String
showLatexExps hexps = concat (map showLatexExp hexps)
--- Transforms an HTML expression into LaTeX string representation.
showLatexExp :: BaseHtml -> String
showLatexExp (BaseText s) = "{" ++ specialchars2tex s ++ "}"
showLatexExp (BaseStruct tag attrs htmlexp)
| tag=="html" = showLatexExps htmlexp
| tag=="head" = "" -- ignore header
| tag=="body" = showLatexExps htmlexp
| tag=="form" = showLatexExps htmlexp
| tag=="h1" = "\\section*{" ++ showLatexExps htmlexp ++ "}\n"
| tag=="h2" = "\\subsection*{" ++ showLatexExps htmlexp ++ "}\n"
| tag=="h3" = "\\subsubsection*{" ++ showLatexExps htmlexp ++ "}\n"
| tag=="h4" = "\\paragraph*{" ++ showLatexExps htmlexp ++ "}\n"
| tag=="h5" = "\\subparagraph*{" ++ showLatexExps htmlexp ++ "}\n"
| tag=="p" = showLatexExps htmlexp ++ "\\par\n"
| tag=="b" = "{\\bf " ++ showLatexExps htmlexp ++ "}"
| tag=="em" = "\\emph{" ++ showLatexExps htmlexp ++ "}"
| tag=="i" = "{\\it " ++ showLatexExps htmlexp ++ "}"
| tag=="tt" = "{\\tt " ++ showLatexExps htmlexp ++ "}"
| tag=="code" = "{\\tt " ++ showLatexExps htmlexp ++ "}"
| tag=="center" = latexEnvironment "center" (showLatexExps htmlexp)
| tag=="pre" = latexEnvironment "verbatim" (textOf htmlexp)
| tag=="font" = showLatexExps htmlexp -- ignore font changes
| tag=="address" = showLatexExps htmlexp
| tag=="blink" = showLatexExps htmlexp
| tag=="sub" = "$_{\\mbox{" ++ showLatexExps htmlexp ++ "}}$"
| tag=="sup" = "$^{\\mbox{" ++ showLatexExps htmlexp ++ "}}$"
| tag=="a" = showLatexExps htmlexp ++
-- add href attribute as footnote, if present:
maybe ""
(\url->"\\footnote{\\tt "++specialchars2tex url++"}\n")
(findHtmlAttr "href" attrs)
| tag=="ul" = latexEnvironment "itemize" (showLatexExps htmlexp)
| tag=="ol" = latexEnvironment "enumerate" (showLatexExps htmlexp)
| tag=="li" = "\\item\n" ++ showLatexExps htmlexp ++ "\n"
| tag=="dl" = latexEnvironment "description" (showLatexExps htmlexp)
| tag=="dt" = "\\item[" ++ showLatexExps htmlexp ++ "]~\\\\\n"
| tag=="dd" = showLatexExps htmlexp
-- tables will be set using the longtable environment,
-- (The package longtable is added by default to every latex document)
| tag=="table" = attrLatexEnv "longtable" (latexTabFormat htmlexp)
(showLatexTableContents htmlexp)
| tag=="tr" = let cells = map showLatexExp htmlexp
in intercalate " & " cells ++ "\\\\\n"
| tag=="td" = showLatexExps htmlexp
| tag=="br" = "\\par\n"
| tag=="hr" = "\\vspace{2ex}\\hrule\n"
| tag=="img" = "{" ++ maybe "{\\tt<IMAGE>}" specialchars2tex
(findHtmlAttr "alt" attrs)
++ "}"
| tag=="input" && maybe "" id (findHtmlAttr "type" attrs) == "hidden" = ""
| otherwise = "{\\tt<"++tag++">}" ++ showLatexExps htmlexp ++
"{\\tt</"++tag++">}"
showLatexExp (BaseAction _) = error "HTML.LaTeX.showLatexExp: BaseAction"
-- create latex environment of name "env" with content "content"
latexEnvironment :: String -> String -> String
latexEnvironment env content = attrLatexEnv env "" content
-- create latex environment of name "env" with content "content"
-- adding the parameters "attr"
attrLatexEnv :: String -> String -> String -> String
attrLatexEnv env attr content
= "\\begin{"++env++"}"++attr++"\n"
++content
++"\n\\end{"++env++"}\n"
-- yield the format of a table, e.g. {lll} from list of html rows.
-- for longtables we set the chunksize big enough
-- to avoid having to rerun latex for inaccurat tables.
latexTabFormat :: [BaseHtml] -> String
latexTabFormat rows = "{" ++ replicate breadth 'l' ++ "}"
++ "\\setcounter{LTchunksize}{" ++ show (length rows + 5) ++ "}%"
where
breadth = foldl max 0 (map getBreadth rows)
-- retrieve the breadth of an Html row
getBreadth :: BaseHtml -> Int
getBreadth row = case row of
BaseStruct "tr" _ tds -> length tds
_ -> error "getBreadth: no row given"
-- tranlate expressions inside tables
showLatexTableContents :: [BaseHtml] -> String
showLatexTableContents hexps = concatMap showLatexTableContent hexps
-- tranlate expressions inside tables
showLatexTableContent :: BaseHtml -> String
showLatexTableContent (BaseText s) = "{" ++ specialchars2tex s ++ "}"
showLatexTableContent (BaseStruct tag attrs htmlexp)
| tag=="html" = showLatexTableContents htmlexp
| tag=="head" = "" -- ignore header
| tag=="body" = showLatexTableContents htmlexp
| tag=="form" = showLatexTableContents htmlexp
| tag=="p" = showLatexTableContents htmlexp ++ "\\par\n"
| tag=="b" = "{\\bf " ++ showLatexTableContents htmlexp ++ "}"
| tag=="em" = "\\emph{" ++ showLatexTableContents htmlexp ++ "}"
| tag=="i" = "{\\it " ++ showLatexTableContents htmlexp ++ "}"
| tag=="tt" = "{\\tt " ++ showLatexTableContents htmlexp ++ "}"
| tag=="font" = showLatexTableContents htmlexp -- ignore font changes
| tag=="address" = showLatexTableContents htmlexp
| tag=="blink" = showLatexTableContents htmlexp
| tag=="a" = showLatexTableContents htmlexp ++
-- add href attribute as footnote, if present:
maybe ""
(\url->"\\footnote{\\tt "++specialchars2tex url++"}\n")
(findHtmlAttr "href" attrs)
| tag=="tr" = let cells = map showLatexTableContent htmlexp
in intercalate " & " cells ++ "\\\\\n"
| tag=="td" = showLatexTableContents htmlexp
| tag=="br" = "\\par\n"
| tag=="hr" = "\\vspace{2ex}\\hrule\n"
| tag=="img" = "{" ++ maybe "{\\tt<IMAGE>}" specialchars2tex
(findHtmlAttr "alt" attrs)
++ "}"
| tag=="input" && maybe "" id (findHtmlAttr "type" attrs) == "hidden" = ""
| otherwise = "{\\tt<"++tag++">}" ++ showLatexTableContents htmlexp ++
"{\\tt</"++tag++">}"
showLatexTableContent (BaseAction _) =
error "HTML.LaTeX.showLatexTableContent: BaseAction"
-- find a specific tag field in a list of HTML attributes:
findHtmlAttr :: String -> [(String,String)] -> Maybe String
findHtmlAttr _ [] = Nothing
findHtmlAttr atag ((t,f):attrs) =
if atag==t then Just f
else findHtmlAttr atag attrs
--- Convert special characters into TeX representation, if necessary.
specialchars2tex :: String -> String
specialchars2tex = htmlSpecialChars2tex . escapeLaTeXSpecials
escapeLaTeXSpecials :: String -> String
escapeLaTeXSpecials [] = []
escapeLaTeXSpecials (c:cs)
| c=='^' = "{\\tt\\char94}" ++ escapeLaTeXSpecials cs
| c=='~' = "{\\tt\\char126}" ++ escapeLaTeXSpecials cs
| c=='\\' = "{\\textbackslash}" ++ escapeLaTeXSpecials cs
| c=='<' = "{\\tt\\char60}" ++ escapeLaTeXSpecials cs
| c=='>' = "{\\tt\\char62}" ++ escapeLaTeXSpecials cs
| c=='_' = "\\_" ++ escapeLaTeXSpecials cs
| c=='#' = "\\#" ++ escapeLaTeXSpecials cs
| c=='$' = "\\$" ++ escapeLaTeXSpecials cs
| c=='%' = "\\%" ++ escapeLaTeXSpecials cs
| c=='{' = "\\{" ++ escapeLaTeXSpecials cs
| c=='}' = "\\}" ++ escapeLaTeXSpecials cs
| otherwise = c : escapeLaTeXSpecials cs
--- Convert special HTML characters into their LaTeX representation,
--- if necessary.
htmlSpecialChars2tex :: String -> String
htmlSpecialChars2tex [] = []
htmlSpecialChars2tex (c:cs)
| c==chr 228 = "{\\\"a}" ++ htmlSpecialChars2tex cs
| c==chr 246 = "{\\\"o}" ++ htmlSpecialChars2tex cs
| c==chr 252 = "{\\\"u}" ++ htmlSpecialChars2tex cs
| c==chr 196 = "{\\\"A}" ++ htmlSpecialChars2tex cs
| c==chr 214 = "{\\\"O}" ++ htmlSpecialChars2tex cs
| c==chr 220 = "{\\\"U}" ++ htmlSpecialChars2tex cs
| c==chr 223 = "{\\ss}" ++ htmlSpecialChars2tex cs
| c=='&' = let (special,rest) = break (==';') cs
in if null rest
then "\\&" ++ htmlSpecialChars2tex special -- wrong format
else htmlspecial2tex special ++
htmlSpecialChars2tex (tail rest)
| otherwise = c : htmlSpecialChars2tex cs
htmlspecial2tex :: String -> String
htmlspecial2tex special
| special=="Auml" = "{\\\"A}"
| special=="Euml" = "{\\\"E}"
| special=="Iuml" = "{\\\"I}"
| special=="Ouml" = "{\\\"O}"
| special=="Uuml" = "{\\\"U}"
| special=="auml" = "{\\\"a}"
| special=="euml" = "{\\\"e}"
| special=="iuml" = "{\\\"\\i}"
| special=="ouml" = "{\\\"o}"
| special=="uuml" = "{\\\"u}"
| special=="szlig" = "{\\ss}"
| special=="Aacute" = "{\\\'A}"
| special=="Eacute" = "{\\\'E}"
| special=="Iacute" = "{\\\'I}"
| special=="Oacute" = "{\\\'O}"
| special=="Uacute" = "{\\\'U}"
| special=="aacute" = "{\\\'a}"
| special=="eacute" = "{\\\'e}"
| special=="iacute" = "{\\\'\\i}"
| special=="oacute" = "{\\\'o}"
| special=="uacute" = "{\\\'u}"
| special=="Agrave" = "{\\`A}"
| special=="Egrave" = "{\\`E}"
| special=="Igrave" = "{\\`I}"
| special=="Ograve" = "{\\`O}"
| special=="Ugrave" = "{\\`U}"
| special=="agrave" = "{\\`a}"
| special=="egrave" = "{\\`e}"
| special=="igrave" = "{\\`\\i}"
| special=="ograve" = "{\\`o}"
| special=="ugrave" = "{\\`u}"
| special=="Acirc" = "{\\^A}"
| special=="Ecirc" = "{\\^E}"
| special=="Icirc" = "{\\^I}"
| special=="Ocirc" = "{\\^O}"
| special=="Ucirc" = "{\\^U}"
| special=="acirc" = "{\\^a}"
| special=="ecirc" = "{\\^e}"
| special=="icirc" = "{\\^\\i}"
| special=="ocirc" = "{\\^o}"
| special=="ucirc" = "{\\^u}"
| special=="Oslash" = "{\\O}"
| special=="oslash" = "{\\o}"
| special=="amp" = "{\\&}"
| special=="ntilde" = "{\\~n}"
| special=="otilde" = "{\\~o}"
| special=="ccedil" = "{\\c{c}}"
| special=="nbsp" = "~"
| special=="quot" = "\""
| special=="lt" = "{$<$}"
| special=="gt" = "{$>$}"
| otherwise = "\\&"++special++";"
------------------------------------------------------------------------------
--- Transforms HTML expressions into a string representation of a complete
--- LaTeX document.
showLatexDoc :: [BaseHtml] -> String
showLatexDoc htmlexps = showLatexDocs [htmlexps]
--- Transforms HTML expressions into a string representation of a complete
--- LaTeX document.
--- The variable "packages" holds the packages to add to the latex document
--- e.g. "ngerman"
showLatexDocWithPackages :: [BaseHtml] -> [String] -> String
showLatexDocWithPackages hexps packages
= showLatexDocsWithPackages [hexps] packages
--- Transforms a list of HTML expressions into a string representation
--- of a complete LaTeX document where each list entry appears
--- on a separate page.
showLatexDocs :: [[BaseHtml]] -> String
showLatexDocs htmlexps_list = showLatexDocsWithPackages htmlexps_list []
--- Transforms a list of HTML expressions into a string representation
--- of a complete LaTeX document where each list entry appears
--- on a separate page.
--- The variable "packages" holds the packages to add to the latex document
--- (e.g., "ngerman").
showLatexDocsWithPackages :: [[BaseHtml]] -> [String] -> String
showLatexDocsWithPackages htmlexps_list packages =
"\\documentclass[12pt]{article}\n"++
concatMap (\p->"\\usepackage{"++p++"}\n") packages++
-- Package longtable is added by default.
"\\usepackage{longtable}"++
"\\nonstopmode\n"++
"\\setlength{\\topmargin}{ -1.5cm}\n"++
"\\setlength{\\oddsidemargin}{0.0cm}\n"++
"\\setlength{\\evensidemargin}{0.0cm}\n"++
"\\setlength{\\marginparwidth}{0.0cm}\n"++
"\\setlength{\\marginparsep}{0.0cm}\n"++
"\\setlength{\\textwidth}{16.5cm}\n"++
"\\setlength{\\textheight}{24.0cm}\n"++
"\\pagestyle{empty}\n"++
"\\begin{document}\n\\sloppy\n"++
"\\addtolength{\\baselineskip}{0.0ex}\n"++
"\\setlength{\\parindent}{0.0ex}\n"++
"\\addtolength{\\parskip}{0.5ex}\n"++
intercalate "\\newpage\n" (map showLatexExps htmlexps_list) ++
"\\end{document}\n"
--- show german latex document
germanLatexDoc :: [BaseHtml] -> String
germanLatexDoc hexps = showLatexDocWithPackages hexps ["ngerman"]
------------------------------------------------------------------------------
|