var gExpectedCharset;
var gOldPref;
var gDetectorList;
var gTestIndex;

function CharsetDetectionTests(aTestFile, aExpectedCharset, aDetectorList)
{
    gExpectedCharset = aExpectedCharset;
    gDetectorList = aDetectorList;

    InitDetectorTests();

    $("testframe").src = aTestFile;

    SimpleTest.waitForExplicitFinish();
}

function InitDetectorTests()
{
    var prefService = Components.classes["@mozilla.org/preferences-service;1"]
	.getService(Components.interfaces.nsIPrefBranch);
    var str =  Components.classes["@mozilla.org/supports-string;1"]
	.createInstance(Components.interfaces.nsISupportsString);

    try {
	gOldPref = prefService
	    .getComplexValue("intl.charset.detector",
			     Components.interfaces.nsIPrefLocalizedString).data;
    } catch (e) {
	gOldPref = "";
    }
    SetDetectorPref(gDetectorList[0]);
    gTestIndex = 0;
    $("testframe").onload = DoDetectionTest;
}

function SetDetectorPref(aPrefValue)
{
    var prefService = Components.classes["@mozilla.org/preferences-service;1"]
	           .getService(Components.interfaces.nsIPrefBranch);
    var str =  Components.classes["@mozilla.org/supports-string;1"]
              .createInstance(Components.interfaces.nsISupportsString);
    str.data = aPrefValue;
    prefService.setComplexValue("intl.charset.detector",
				Components.interfaces.nsISupportsString, str);
    gCurrentDetector = aPrefValue;
}

function DoDetectionTest() {
    var iframeDoc = $("testframe").contentDocument;
    var charset = iframeDoc.characterSet;

    is(charset, gExpectedCharset,
       "decoded as " + gExpectedCharset + " by " + gDetectorList[gTestIndex]);

    if (++gTestIndex < gDetectorList.length) {
	SetDetectorPref(gDetectorList[gTestIndex]);
	iframeDoc.location.reload();
    } else {
	CleanUpDetectionTests();
    }
}

function CleanUpDetectionTests() {
    SetDetectorPref(gOldPref);
    SimpleTest.finish();
}