require 'formula'

class SqliteFunctions < Formula
  url 'http://www.sqlite.org/contrib/download/extension-functions.c?get=25', :using  => NoUnzipCurlDownloadStrategy
  md5 '3a32bfeace0d718505af571861724a43'
  version '2010-01-06'
end

class SqliteDocs < Formula
  url 'http://www.sqlite.org/sqlite-doc-3070900.zip'
  sha1 '2d4a25f75cc6b7251f1b49b828f9fd1d699fc8a2'
  version '3.7.9'
end

class Sqlite < Formula
  homepage 'http://sqlite.org/'
  url 'http://www.sqlite.org/sqlite-autoconf-3070900.tar.gz'
  sha1 'a9da98a4bde4d9dae5c29a969455d11a03600e11'
  version '3.7.9'

  depends_on 'readline' => :optional

  def options
  [
    ["--with-docs", "Install HTML documentation"],
    ["--with-rtree", "Enable the R*Tree index module"],
    ["--with-fts", "Enable the FTS Module"],
    ["--universal", "Build a universal binary"],
    ["--with-functions", "Enable more math and string functions for SQL queries"]
  ]
  end

  def install
    # O2 and O3 leads to corrupt/invalid rtree indexes
    # http://groups.google.com/group/spatialite-users/browse_thread/thread/8e1cfa79f2d02a00#
    ENV.Os

    ENV.append 'CPPFLAGS', "-DSQLITE_ENABLE_RTREE" if ARGV.include? "--with-rtree"
    ENV.append 'CPPFLAGS', "-DSQLITE_ENABLE_FTS3 -DSQLITE_ENABLE_FTS3_PARENTHESIS" if ARGV.include? "--with-fts"

    # enable these options by default
    ENV.append 'CPPFLAGS', "-DSQLITE_ENABLE_COLUMN_METADATA"
    ENV.append 'CPPFLAGS', "-DSQLITE_ENABLE_STAT3"

    ENV.universal_binary if ARGV.build_universal?

    system "./configure", "--prefix=#{prefix}", "--disable-dependency-tracking",
                          (ARGV.include? "--with-functions") ? "--enable-dynamic-extensions" : ""
    system "make install"

    if ARGV.include? "--with-functions"
      d=Pathname.getwd
      SqliteFunctions.new.brew { mv 'extension-functions.c?get=25', d + 'extension-functions.c' }
      system ENV.cc, "-fno-common", "-dynamiclib", "extension-functions.c", "-o", "libsqlitefunctions.dylib", *ENV.cflags.split
      lib.install "libsqlitefunctions.dylib"
    end

    SqliteDocs.new.brew { doc.install Dir['*'] } if ARGV.include? "--with-docs"
  end

  if ARGV.include? "--with-functions"
    def caveats
      <<-EOS.undent
        Usage instructions for applications calling the sqlite3 API functions:

          In your application, call sqlite3_enable_load_extension(db,1) to
          allow loading external libraries.  Then load the library libsqlitefunctions
          using sqlite3_load_extension; the third argument should be 0.
          See http://www.sqlite.org/cvstrac/wiki?p=LoadableExtensions.
          Select statements may now use these functions, as in
          SELECT cos(radians(inclination)) FROM satsum WHERE satnum = 25544;

        Usage instructions for the sqlite3 program:

          If the program is built so that loading extensions is permitted,
          the following will work:
           sqlite> SELECT load_extension('#{lib}/libsqlitefunctions.dylib');
           sqlite> select cos(radians(45));
           0.707106781186548
      EOS
    end
  end
end