#!/usr/bin/env python

# ------------------------------------------------------------------------------

#
# Disclaimer:
#
# DTN grants you an nonexclusive copyright license to use this code and you can
# use it to prepare similar functions tailored to your own needs.
#
# The code is provided for illustrative purposes only and has not been tested under
# all conditions.  For that reason, DTN provides this code to you "AS IS" without
# any warranties of any kind.
#

# ------------------------------------------------------------------------------

#
# Retrieve a daily history report and present result as a SVG chart.
#

# Imports
import PXWeb

# ------------------------------------------------------------------------------

# PXWeb access credentials
USER = 'YOUR_USER'
PSWD = 'YOUR_PASSWORD'

# Search pattern to send to PXWeb
PATTERN = '@C`## 20'

# Max number of history entries to return for each symbol
LIMIT = 500

# GetDailyHistory request string and CSV fields for response
FIELDS = ( 'Date', 'Open', 'Close', 'High', 'Low', 'OI', 'Volume' )

# Name of output file
OUT_FILE = 'result.svg'

# ------------------------------------------------------------------------------

# Chart size
WIDTH = 900
HEIGHT = 400

# Coordinates at origin
X0 = 30
Y0 = 60

# Grid count and title on X axis
GRID_COUNT = 10
X_TITLE = 'DAYS BEFORE {}'

# SVG objects
SVG_LINE = '<line x1="{}" y1="{}" x2="{}" y2="{}" stroke-dasharray="1px"/>\n'
SVG_POLYLINE = '<polyline id="{0}" cursor="pointer" stroke="grey" stroke-width="1" points="{1}" onclick="show( \'{0}\' )"><title>{0}</title></polyline>\n'
SVG_RECT = '<rect x="{}" y="{}" width="{}" height="{}"/>\n'
SVG_TEXT = '<text x="{}" y="{}" font-size="{}" >{}</text>\n'
SVG_TEXT_MAP = '<text x="{0}" y="{1}" cursor="pointer" font-size="{2}" onclick="show( \'{3}\' )">{3}</text>\n'

# Start of SVG file
SVG_HEAD = '''
<?xml version="1.0" standalone="no"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">

<svg xmlns="http://www.w3.org/2000/svg" version="1.1">

<style type="text/css">
	line
		{ fill:none; stroke:#fe5a1d; stroke-width:1; }
	polyline
		{ fill:none; }
	rect
		{ fill:white; stroke:#fe5a1d; stroke-width:3; fill-opacity:0.1; stroke-opacity:0.9; }
	text
		{ fill:none; stroke:gray; stroke-width:1; }
</style>

<script>
	function show( symbol ) {
		var polyline = document.getElementById( symbol );
		width = polyline.getAttribute( "stroke-width" );
	
		if( width == 1 ) {
			polyline.setAttribute( 'stroke-width', 3 );
			polyline.setAttribute( 'stroke', 'black' );
		} else {
			polyline.setAttribute( 'stroke-width', 1 );
			polyline.setAttribute( 'stroke', 'gray' );
		}
	}
</script>

'''

# ------------------------------------------------------------------------------

# Open output file and write header
ofile = open( OUT_FILE, 'w' )
ofile.write( SVG_HEAD[ 1: ] )

# Get PXWeb client object
pxWeb = PXWeb.PXServiceWebClient( USER, PSWD )

# Send GetDailyHistory request for current search pattern and get an XML tree
xml = pxWeb.getDailyHistory( symbol=PATTERN, limit=LIMIT )

# Build a PXDailyHistoryData object from XML tree
h = PXWeb.PXDailyHistoryData( xml )

# Calculate constants to adjust chart to fit
daysFact = WIDTH / float( h.daysMax - h.daysMin )
priceFact = HEIGHT / float( h.priceMax - h.priceMin )

# Write rectangle and titles
ofile.write( SVG_RECT.format( X0, Y0, WIDTH, HEIGHT ) )
title = X_TITLE.format(h.today.strftime( '%Y-%m-%d' ))
ofile.write( SVG_TEXT.format( X0 + ( WIDTH - 6 * len( title ) ) / 2, Y0 + HEIGHT + 35, 12, title ) )
ofile.write( SVG_TEXT.format( X0, Y0 - 35, 16, 'GetDailyHistory: ' + PATTERN ) )

# Write vertical grid
for x in range( X0, X0 + WIDTH, WIDTH // GRID_COUNT ):
	days = ( WIDTH - x + X0 ) / daysFact + h.daysMin
	ofile.write( SVG_TEXT.format( x - 5, Y0 + HEIGHT + 16, 10, f'days' ) )
	ofile.write( SVG_LINE.format( x, Y0, x, Y0 + HEIGHT ) )

# Write horizontal grid
for y in range( Y0, Y0 + HEIGHT + 1, HEIGHT // GRID_COUNT ):
	price = ( HEIGHT - y + Y0 ) / priceFact + h.priceMin
	ofile.write( SVG_TEXT.format( X0 + WIDTH + 5, y, 10, f'${price:.2f}' ) )
	ofile.write( SVG_LINE.format( X0, y, X0 + WIDTH, y ) )

# Build a polyline for each symbol and write
for symbol in h.symbols:

	# String of coordinates
	coords = ''

	# Populate string of coordinates
	for days, price in h.data[ symbol ]:
		x = WIDTH - int( ( days - h.daysMin ) * daysFact ) + X0
		y = HEIGHT - int( ( price - h.priceMin ) * priceFact ) + Y0
		coords += f'{x},{y} '

	# Write final polyline
	ofile.write( SVG_POLYLINE.format( symbol, coords ) )

# Starting coordinates for symbol list
x = 0

# Write symbol list
for symbol in h.symbols:
	ofile.write( SVG_TEXT_MAP.format( x + X0, Y0 - 10, 10, symbol ) )
	x = x + WIDTH / 20

# Write tail
ofile.write( '</svg>' )
ofile.close()

# Notify
print(f'Result ready in file "{OUT_FILE}".')