'''
Copyright 2010 Expert Sleepers. All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are
permitted provided that the following conditions are met:

   1. Redistributions of source code must retain the above copyright notice, this list of
      conditions and the following disclaimer.

   2. Redistributions in binary form must reproduce the above copyright notice, this list
      of conditions and the following disclaimer in the documentation and/or other materials
      provided with the distribution.

THIS SOFTWARE IS PROVIDED BY EXPERT SLEEPERS ``AS IS'' AND ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL EXPERT SLEEPERS OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

The views and conclusions contained in the software and documentation are those of the
authors and should not be interpreted as representing official policies, either expressed
or implied, of Expert Sleepers.
'''

'''
Calibration data reading/writing class.
v1.0.0 (14/1/2010)
v1.0.1 (3/3/2010) - removed use of 'with' and 'format' for Python 2.5 compatibility
'''

import sys

class CalibrationData:

	def __init__(self):
		self.clear()
		
	def clear(self):
		self._values = [0.0] * 129
		self._valid = [False] * 129
		
	def value(self, index):
		if index < 0 or index >= 129:
			raise RuntimeError( 'index %d out of range' % index )
		if isinstance( index, int ):
			return self._values[ index ]
		i = int( index )
		f = index - float( i )
		v0 = self._values[ i ]
		v1 = self._values[ i+1 ]
		return v0 + f * ( v1 - v0 )
	
	def dump(self):
		print self._values
		print self._valid
		for i, v in enumerate( self._valid ):
			if v:
				print '%d: %f' % ( i, self._values[i] )

	def load(self, filename):
		self.clear()
		file = open( filename, 'r' )
		lines = file.readlines()
		file.close()
		if lines[0] != 'Silent Way Calibration Data\n':
			raise RuntimeError( 'failed to read header' )
		if lines[1] != 'version: 1\n':
			raise RuntimeError( 'failed to read version' )
		for line in lines[2:]:
			bits = line[:-1].split( ' ' )
			index = int( bits[0] )
			value = float( bits[1] )
			if index < 0 or index >= 129:
				raise RuntimeError( 'index %d out of range' % index )
			if abs( value ) > 1.0:
				raise RuntimeError( 'value %f out of range' % value )
			self._valid[ index ] = True
			self._values[ index ] = value
		# fill in gaps
		valid = [ i for i, v in enumerate( self._valid ) if v ]
		firstValid = valid[0]
		lastValid = valid[-1]
		for i in range( firstValid, lastValid+1 ):
			if not self._valid[ i ]:
				low = i-1
				high = i+1
				while not self._valid[low]:
					low -= 1
				while not self._valid[high]:
					high += 1
				v0 = self._values[ low ]
				v1 = self._values[ high ]
				self._values[ i ] = v0 + ( v1 - v0 ) * ( i - low )/float( high - low )
			
	def save(self, filename):
		file = open( filename, 'w' )
		file.write( 'Silent Way Calibration Data\n' )
		file.write( 'version: 1\n' )
		for i in range( 0, 129 ):
			if self._valid[ i ]:
				file.write( '%d %.8f\n' % ( i, self._values[ i ] ) )
		file.close()

if __name__ == '__main__':
	# simple test - load and save a file
	cd = CalibrationData()
	cd.load( sys.argv[1] )
	cd.dump()
	print cd.value( 15 )
	print cd.value( 10.5 )
	cd.save( sys.argv[2] )