#!/bin/sh
true = [[

# Shell/Lua script to convert from MobileDB to JFile

input="$1"
output="$2"
if [ -z "$input" ]; input="-"; fi
if [ -z "$output" ]; output="-"; fi

pdbconv unpack "$input" m2j.ascii$$
echo "dofile('m2j.ascii$$'); dofile('$0'); Database = m2j(Database)" |
pdbconv pack - "$output"
rc="$?"
rm -f m2j.ascii$$

exit $rc
]]

$debug
function searchcat(recs, c)
  local i
  i = 1  
  while recs[i] and recs[i].category ~= c do
    i = i + 1
  end
  if not recs[i] then error("MDB had no record with category " .. c) 
  else return recs[i].data
  end
end

function m2j(mdb)
  local jdb, f, r, r2, i, j, fnames, numfields, nxt
  if mdb.type ~= "Mdb1" or mdb.creator ~= "Mdb1" then
    error("Source database is not a MobileDB database")
  end
  jdb = { name = "J: " .. gsub(mdb.name, "^[MJ]: ", ""), 
          version = 1, type = "JbDb", creator = "JBas",
	  dates = mdb.dates,
          appInfo = { version = 452, fields = { } },
          records = { }  -- records and fields have to get filled in
        }

  fnames = searchcat(mdb.records, 1)
  fwidths = searchcat(mdb.records, 6)
 
  fnames = fnames.fields
  fwidths = fwidths.fields


-- write("fnames = ") show(fnames)
-- write("fwidths = ") show(fwidths)

  i = 1
  -- for now, all MobileDB stuff is strings.  We could do better by recognizing
  -- and converting integers and dates
  while fnames[i] do
    jdb.appInfo.fields[i] =
       { type = "string", typenum = 1, width = fwidths[i], name = fnames[i] }
    i = i + 1
  end
  numfields = i - 1

-- write("database has ", numfields, " fields\n")
  nxt = 1
  i = 1
  while mdb.records[i] do
    if mdb.records[i].data.type == "Data record" then
      r = mdb.records[i].data.fields
-- write("converting record "); show(r)
      r2 = { }
      j = 1
      while j <= numfields do
-- write("converting field ", j, "\n")
        if r[j] then r2[j] = r[j] else r2[j] = "" end
        j = j + 1
      end
-- write("new fields is ") show(r2)
      jdb.records[nxt] = { category = 0, data = r2 }
-- write("result is ") show(jdb.records[nxt])
      nxt = nxt + 1
    end
    i = i + 1
  end

  return jdb
end

 -- for debugging
function show(x, indent)
  local i, v, i2, pfx, nl
  nl = ""
  if not indent then indent = ""; nl = "\n" end
  if type(x) == "table" then
    write("{\n")
    if x[1] then
      i = 1
      pfx = indent .. "  "
      while x[i] do
        write(pfx); show(x[i], indent .. "  ")
        pfx = ",\n" .. indent .. "  "
        i = i + 1
      end
    else
      i = nil
      pfx = indent .. "  "
      repeat
        i, v = next(x, i)
        if i ~= nil then
          write(pfx, i, " = "); show(v, indent .. "  ")
          pfx = ",\n" .. indent .. "  "
        end
      until (i == nil)
    end
    write ("\n", indent, "}")
  elseif type(x) == "string" then
    write(format('%q', x))
  elseif type(x) == "number" then
    write(x)
  elseif type(x) == "nil" then
    write("nil")
  else 
    print(x)
  end
  write(nl)
end