#
# JSON-RPC demo client contributed by Christoph Zwerschke
#

try:
	import simplejson
except ImportError:
	simplejson = None

from ExamplePage import ExamplePage


class JSONRPCClient(ExamplePage):
	"""Demo client for using the JSON-RPC example."""

	def writeJavaScript(self):
		ExamplePage.writeJavaScript(self)
		if not simplejson:
			return
		self.write('''\
			<script type="text/javascript" src="jsonrpc.js"></script>
			<script type="text/javascript">
			<!--
			jsonrpc = new JSONRpcClient("JSONRPCExample");
			methods = jsonrpc.system.listMethods();
			function dojsonrpc() {
				p = document.getElementById("parameter").value;
				i = document.getElementById("method").selectedIndex;
				r = jsonrpc[methods[i]](p);
				document.getElementById("result").value = r;
			}
			-->
			</script>
		''')

	def writeContent(self):
		self.write('''\
			<h3>JSON-RPC Example</h3>
			<p>This example shows how you can call methods
			of a <a href="http://json-rpc.org">JSON-RPC</a> servlet
			built with Webware for Python from your web browser
			via JavaScript (which has to be activated to run this demo).
			<noscript><span style="color:red">
			Unfortunately, JavaScript is not activated.
			</span></noscript></p>
			<p>The example uses a JSON-RPC JavaScript client
			based on Jan-Klaas' "JavaScript o lait" library
			(<a href="http://jsolait.net">jsolait</a>).
			You can also use other JavaScript libraries and toolkits
			such as <a href="http://dojotoolkit.org">dojo</a> or
			<a href="http://pyjamas.pyworks.org">pyjamas</a>
			for that purpose.</p>
			<p>In order to run the JSON-RPC servlet,
			<a href="http://cheeseshop.python.org/pypi/simplejson">simplejson</a>
			must be installed on your server.''')
		if not simplejson:
			self.write(''' <span style="color:red">
			Unfortunately, simplejson is not installed.</span>''')
			return
		self.write('''</p>
			<p>Type in any example text to be used as input parameter,
			choose one of the available methods to be invoked by the
			example servlet and press the button to display the result.</p>
			<table>
			<tr align="center">
			<th>Input parameter</th>
			<th>Remote method</th>
			<th>Result</th>
			</tr><tr align="center">
			<td>
			<input id="parameter" type="text" size="20" value="Hello, World!">
			</td><td>
			<select id="method" size="1">
			<script type="text/javascript">
			<!--
			for (m in methods)
				document.writeln('<option>' + methods[m] + '</option>');
			-->
			</script>
			</select>
			</td><td>
			<input type="text" size="20" id="result">
			</td>
			</tr><tr align="center">
			<td colspan="3">
			<input type="button" value="Invoke remote method"
				onclick="dojsonrpc()">
			</td>
			</tr>
			</table>
		''')