#!/usr/bin/env rake

require 'uri'
require 'tempfile'
require 'rbconfig'
require 'rake/clean'
require 'rake/extensiontask'
require 'rake/extensioncompiler'

MISCDIR = BASEDIR + 'misc'

NUM_CPUS = if File.exist?('/proc/cpuinfo')
  File.read('/proc/cpuinfo').scan('processor').length
elsif RUBY_PLATFORM.include?( 'darwin' )
  `system_profiler SPHardwareDataType | grep 'Cores' | awk '{print $5}'`.chomp
else
  1
end

# Cross-compilation constants
OPENSSL_VERSION            = ENV['OPENSSL_VERSION'] || '1.0.0e'
POSTGRESQL_VERSION         = ENV['POSTGRESQL_VERSION'] || '9.1.1'

COMPILE_HOME               = Pathname( "./build" ).expand_path
STATIC_SOURCESDIR          = COMPILE_HOME + 'sources'
STATIC_BUILDDIR            = COMPILE_HOME + 'builds'

# Static OpenSSL build vars
STATIC_OPENSSL_BUILDDIR    = STATIC_BUILDDIR + "openssl-#{OPENSSL_VERSION}"

OPENSSL_SOURCE_URI         =
  URI( "http://www.openssl.org/source/openssl-#{OPENSSL_VERSION}.tar.gz" )
OPENSSL_TARBALL            = STATIC_SOURCESDIR + File.basename( OPENSSL_SOURCE_URI.path )
OPENSSL_MAKEFILE           = STATIC_OPENSSL_BUILDDIR + 'Makefile'

LIBSSLEAY32                = STATIC_OPENSSL_BUILDDIR + 'libssleay32.a'
LIBEAY32                   = STATIC_OPENSSL_BUILDDIR + 'libeay32.a'

OPENSSL_PATCHES            = Rake::FileList[ MISCDIR + "openssl-#{OPENSSL_VERSION}.*.patch" ]

# Static PostgreSQL build vars
STATIC_POSTGRESQL_BUILDDIR = STATIC_BUILDDIR + "postgresql-#{POSTGRESQL_VERSION}"
POSTGRESQL_SOURCE_URI      = begin
  uristring = "http://ftp9.us.postgresql.org/pub/mirrors/postgresql/source/" +
    "v%s/postgresql-%s.tar.bz2" % [ POSTGRESQL_VERSION, POSTGRESQL_VERSION ]
  URI( uristring )
end
POSTGRESQL_TARBALL         = STATIC_SOURCESDIR + File.basename( POSTGRESQL_SOURCE_URI.path )

STATIC_POSTGRESQL_SRCDIR   = STATIC_POSTGRESQL_BUILDDIR + 'src'
STATIC_POSTGRESQL_LIBDIR   = STATIC_POSTGRESQL_SRCDIR + 'interfaces/libpq'
STATIC_POSTGRESQL_INCDIR   = STATIC_POSTGRESQL_SRCDIR + 'include'

POSTGRESQL_GLOBAL_MAKEFILE = STATIC_POSTGRESQL_SRCDIR + 'Makefile.global'
POSTGRESQL_SHLIB_MAKEFILE  = STATIC_POSTGRESQL_SRCDIR + 'Makefile.shlib'
POSTGRESQL_SHLIB_MF_ORIG   = STATIC_POSTGRESQL_SRCDIR + 'Makefile.shlib.orig'
POSTGRESQL_LIB             = STATIC_POSTGRESQL_LIBDIR + 'libpq.a'

CROSS_PREFIX = Rake::ExtensionCompiler.mingw_host


# clean intermediate files and folders
CLEAN.include( STATIC_BUILDDIR.to_s )


ENV['RUBY_CC_VERSION'] ||= '1.8.7:1.9.3'

def download(url, save_to)
  part = save_to+".part"
  sh "wget #{url.to_s.inspect} -O #{part.inspect} || curl #{url.to_s.inspect} -o #{part.inspect}"
  FileUtils.mv part, save_to
end

def run(*args)
  sh *args
end

#####################################################################
### C R O S S - C O M P I L A T I O N - T A S K S
#####################################################################


directory STATIC_SOURCESDIR.to_s

#
# Static OpenSSL build tasks
#
directory STATIC_OPENSSL_BUILDDIR.to_s

# openssl source file should be stored there
file OPENSSL_TARBALL => STATIC_SOURCESDIR do |t|
  download( OPENSSL_SOURCE_URI, t.name )
end

# Extract the openssl builds
file STATIC_OPENSSL_BUILDDIR => OPENSSL_TARBALL do |t|
  puts "extracting %s to %s" % [ OPENSSL_TARBALL, STATIC_OPENSSL_BUILDDIR.parent ]
  STATIC_OPENSSL_BUILDDIR.mkpath
  run 'tar', '-xzf', OPENSSL_TARBALL.to_s, '-C', STATIC_OPENSSL_BUILDDIR.parent.to_s
  OPENSSL_MAKEFILE.unlink if OPENSSL_MAKEFILE.exist?

  OPENSSL_PATCHES.each do |patchfile|
    puts "  applying patch #{patchfile}..."
    run 'patch', '-Np1', '-d', STATIC_OPENSSL_BUILDDIR.to_s,
      '-i', File.expand_path( patchfile, BASEDIR )
  end
end

CMD_PRELUDE = [
  'env',
  "CC=#{CROSS_PREFIX}-gcc",
  "CFLAGS=-DDSO_WIN32",
  "AR=#{CROSS_PREFIX}-ar",
  "RANLIB=#{CROSS_PREFIX}-ranlib"
]


# generate the makefile in a clean build location
file OPENSSL_MAKEFILE => STATIC_OPENSSL_BUILDDIR do |t|
  Dir.chdir( STATIC_OPENSSL_BUILDDIR ) do
    cmd = CMD_PRELUDE.dup
    cmd << "./Configure" << 'mingw'

    run( *cmd )
  end
end

desc "compile static openssl libraries"
task :openssl_libs => [ LIBSSLEAY32, LIBEAY32 ]

task :compile_static_openssl => OPENSSL_MAKEFILE do |t|
  Dir.chdir( STATIC_OPENSSL_BUILDDIR ) do
    cmd = CMD_PRELUDE.dup
    cmd << 'make' << "-j#{NUM_CPUS}" << 'build_libs'

    run( *cmd )
  end
end

desc "compile static #{LIBEAY32}"
file LIBEAY32 => :compile_static_openssl do |t|
  FileUtils.cp( STATIC_OPENSSL_BUILDDIR + 'libcrypto.a', LIBEAY32.to_s )
end

desc "compile static #{LIBSSLEAY32}"
file LIBSSLEAY32 => :compile_static_openssl do |t|
  FileUtils.cp( STATIC_OPENSSL_BUILDDIR + 'libssl.a', LIBSSLEAY32.to_s )
end



#
# Static PostgreSQL build tasks
#
directory STATIC_POSTGRESQL_BUILDDIR.to_s


# postgresql source file should be stored there
file POSTGRESQL_TARBALL => STATIC_SOURCESDIR do |t|
  download( POSTGRESQL_SOURCE_URI, t.name )
end

# Extract the postgresql sources
file STATIC_POSTGRESQL_BUILDDIR => POSTGRESQL_TARBALL do |t|
  puts "extracting %s to %s" % [ POSTGRESQL_TARBALL, STATIC_POSTGRESQL_BUILDDIR.parent ]
  STATIC_POSTGRESQL_BUILDDIR.mkpath
  run 'tar', '-xjf', POSTGRESQL_TARBALL.to_s, '-C', STATIC_POSTGRESQL_BUILDDIR.parent.to_s
  mv POSTGRESQL_SHLIB_MAKEFILE, POSTGRESQL_SHLIB_MF_ORIG
end

# generate the makefile in a clean build location
file POSTGRESQL_GLOBAL_MAKEFILE => [ STATIC_POSTGRESQL_BUILDDIR, :openssl_libs ] do |t|
  options = [
    '--target=i386-mingw32',
    "--host=#{Rake::ExtensionCompiler.mingw_host}",
    '--with-openssl',
    '--without-zlib',
    '--disable-shared',
  ]

  Dir.chdir( STATIC_POSTGRESQL_BUILDDIR ) do
    configure_path = STATIC_POSTGRESQL_BUILDDIR + 'configure'
    cmd = [ configure_path.to_s, *options ]
    cmd << "CFLAGS=-L#{STATIC_OPENSSL_BUILDDIR}"
    cmd << "LDFLAGS=-L#{STATIC_OPENSSL_BUILDDIR}"
    cmd << "LDFLAGS_SL=-L#{STATIC_OPENSSL_BUILDDIR}"
    cmd << "LIBS=-lwsock32 -lws2_32 -lgdi32"
    cmd << "CPPFLAGS=-I#{STATIC_OPENSSL_BUILDDIR}/include"

    run( *cmd )
  end
end


# patch the Makefile.shlib -- depend on the build dir so it's only
# rewritten if the tarball is re-extracted.
file POSTGRESQL_SHLIB_MAKEFILE => POSTGRESQL_SHLIB_MF_ORIG do |t|
  tf = Tempfile.new( POSTGRESQL_SHLIB_MAKEFILE.basename )
  POSTGRESQL_SHLIB_MF_ORIG.open( File::RDONLY ) do |ifh|
    ifh.each_line do |line|
      tf.print( line.sub(/^(\s*haslibarule\s*=\s*yes)/, "# \\1 ") )
    end
  end
  tf.close

  FileUtils.mv( tf.path, t.name, :verbose => $puts )
end


# make libpq.a
task POSTGRESQL_LIB => [ POSTGRESQL_GLOBAL_MAKEFILE, POSTGRESQL_SHLIB_MAKEFILE ] do |t|
  Dir.chdir( POSTGRESQL_LIB.dirname ) do
    sh 'make', "-j#{NUM_CPUS}", POSTGRESQL_LIB.basename.to_s, 'PORTNAME=win32'
  end
end


#desc 'compile static libpg.a'
task :static_libpq => POSTGRESQL_LIB

desc 'cross compile pg for win32'
task :cross do
  ENV['CROSS_COMPILING'] = 'yes'
end
task :cross => [ :mingw32, :static_libpq ]

task :mingw32 do
  # Use Rake::ExtensionCompiler helpers to find the proper host
  unless Rake::ExtensionCompiler.mingw_host then
    warn "You need to install mingw32 cross compile functionality to be able to continue."
    warn "Please refer to your distribution/package manager documentation about installation."
    fail
  end
end