# R program to create html from .csv file and template.
# This program is indended to be called from the shell file "cgihtml".
# It creates cgihtmllog.tmp with comments.

# Shell file "cgihtml" writes user's request to "cgihtmlInfile.tmp"
# and "cgihtmlOutfile.tmp" and "cgireadDBfilename.tmp"

# Get csv filename
dataName=scan("cgireadDBfile.tmp", what="", quiet=TRUE)
if (!file.exists(dataName)) {
  write(paste("Can't open",dataName), file="cgihtmllog.tmp")
  quit(save="no")
}
baseName=dataName
i=nc=nchar(dataName)
while (i>1) {
  if (substring(dataName,i,i)==".") {
    baseName=substring(dataName,1,i-1)
    break
  }
  i=i-1
}
csvName=paste(baseName,".csv",sep="")
if (!file.exists(csvName)) {
  write(paste("Can't open", csvName), file="cgihtmllog.tmp")
  quit(save="no")
}
data=read.table(csvName, header=TRUE, sep=",", as.is=TRUE)
if (any(names(data)=="category")) data=data[order(data$category),]

# Read filenames from these files and verify that they exist.
if (!file.exists("cgihtmlInfile.tmp")) {
  write("Can't open cgihtmlInfile.tmp", file="cgihtmllog.tmp")
  quit(save="no")
}
templateName=scan("cgihtmlInfile.tmp", what="", quiet=TRUE)
if (!file.exists(templateName)) {
  write(paste("Can't open",templateName), file="cgihtmllog.tmp")
  quit(save="no")
}
if (!file.exists("cgihtmlOutfile.tmp")) {
  write("Can't open cgihtmlOutfile.tmp", file="cgihtmllog.tmp")
  quit(save="no")
}
outName=scan("cgihtmlOutfile.tmp", what="", quiet=TRUE)

# Read data from template file (one field per line)
lines=scan(templateName, sep="\n", strip.white=TRUE, what="", quiet=TRUE)
lines=lines[nchar(lines)>0]
nl=length(lines)
if (nl==0) {
  write(paste(templateName, "is empty."), file="cgihtmllog.tmp")
  quit(save="no")
}

# Record lines with equal signs (start of field) and positions of equal signs
tableloc=as.numeric(regexpr("^TABLE",lines))
if (sum(tableloc==1)!=1) {
  write(paste(templateName,"must have exactly one TABLE line."), file="cgihtmllog.tmp")
  quit(save="no")
}
tableloc=seq(along=lines)[tableloc==1]

# Create html file
write(lines[1:(tableloc-1)], file=outName, ncolumns=1, append=FALSE)


write("<table border=5>",  file=outName, ncolumns=1, append=TRUE)
tmp=paste(names(data),collapse="</th><th>")
write(paste("<tr><th>",tmp,"</th></tr>"),  file=outName, ncolumns=1, append=TRUE)
for (i in 1:nrow(data)) {
  tmp=paste(unlist(data[i,]),collapse="</td><td>")
  write(paste("<tr><td>",tmp,"</th></td>"),  file=outName, ncolumns=1, append=TRUE)
}
write("</table>",  file=outName, ncolumns=1, append=TRUE)



write(lines[(tableloc+1):length(lines)], file=outName, ncolumns=1, append=TRUE)
write(paste("Successfully created", outName), file="cgihtmllog.tmp")