public static call HasBlock(this call kall)
{
if (kall.block != null && kall.block.calls.Count > 0)
{
return(kall);
}
throw ObjException.BlockRequired(kall);
}
public static call NoBlock(this call kall)
{
if (kall.block != null && kall.block.calls.Count > 0)
{
throw ObjException.BlockNotAccepted(kall);
}
return(kall);
}
public static call DomBuilt(this call kall, IDocument dom)
{
if (dom == null)
{
throw ObjException.MissingDomAndCalled(kall);
}
return(kall);
}
public async Task eval(call kall)
{
bool hadResult = resultSet;
bool addedResult = await funcs[kall.name](kall);
if (hadResult && addedResult)
{
throw ObjException.ExpressionDiscarded(kall, trace.FindLast(x => true));
}
hadResult = addedResult;
trace.Add(kall);
}
public static call ElementSelected(this call kall, obj env)
{
var lastCall = env.trace.Last();
if (lastCall.name == "sel" || lastCall.name == "id")
{
return(kall);
throw ObjException.MissingElementAndCalled(kall);
}
return(kall);
}
public static call ArityMatches(this call kall, int expected)
{
if (kall.args == null && expected == 0)
{
return(kall);
}
if (kall.args?.Count != expected)
{
throw ObjException.ArityMismatch(kall, 1);
}
return(kall);
}
public static obj TopLevel()
{
var topLevel = new obj();
BrowsingContext ctx = new BrowsingContext(Configuration.Default.WithDefaultLoader());
IDocument dom = null;
IElement el = null;
topLevel.funcs["true"] = async(kall) => {
Ensure.ArityMatches(kall, 0).NoBlock();
topLevel.result = true;
return(true);
};
topLevel.funcs["false"] = async(kall) => {
Ensure.ArityMatches(kall, 0).NoBlock();
topLevel.result = false;
return(true);
};
topLevel.funcs["out"] = async(kall) => {
Ensure.ArityMatches(kall, 1);
topLevel.Output[kall.args[0]] = topLevel.result;
topLevel.result = null;
return(false);
};
topLevel.funcs["all"] = async(kall) => {
Ensure.HasBlock(kall);
foreach (call k in kall.block.calls)
{
await topLevel.eval(k);
if (topLevel.resultSet && topLevel.result is false)
{
topLevel.result = false;
return(false);
}
}
// If we didn't find any results set to false, it then set result to true
topLevel.result = true;
return(false);
};
topLevel.funcs["any"] = async(kall) => {
Ensure.HasBlock(kall);
foreach (call k in kall.block.calls)
{
await topLevel.eval(k);
if (topLevel.resultSet && topLevel.result is true)
{
return(false);
}
}
// If we didn't find any truthy values, then
topLevel.result = false;
return(false);
};
topLevel.funcs["none"] = async(kall) => {
Ensure.ArityMatches(kall, 0).HasBlock();
foreach (call k in kall.block.calls)
{
await topLevel.eval(k);
if (topLevel.resultSet && topLevel.result is true)
{
topLevel.result = false;
return(false);
}
}
// If we didn't find any truthy values, then this was true
topLevel.result = true;
return(false);
};
topLevel.funcs["has-text"] = async(kall) =>
{
Ensure.ArityMatches(kall, 1).NoBlock().ElementSelected(topLevel);
topLevel.result = el.TextContent.Contains(kall.args[0]);
return(true);
};
topLevel.funcs["sel"] = async(kall) => {
Ensure.ArityMatches(kall, 1).NoBlock().DomBuilt(dom);
el = dom.QuerySelector(kall.args[0]);
return(false);
};
topLevel.funcs["id"] = async(kall) => {
Ensure.ArityMatches(kall, 1).DomBuilt(dom).NoBlock();
el = dom.GetElementById(kall.args[0]);
return(false);
};
topLevel.funcs["site"] = async(kall) => {
Ensure.ArityMatches(kall, 1);
dom = await ctx.OpenAsync(kall.args[0]);
var outName = kall.block?.calls?.FirstOrDefault(x => x.name == "out")?.args?[0] ?? kall.args[0];
if (dom == null)
{
var failMsg = ObjException.UrlFailed(kall).Message;
topLevel.Output[$"{outName}-error"] = failMsg;
topLevel.Output[outName] = false;
return(false);
}
if (kall.block != null)
{
try
{
await kall.block.eval(topLevel);
}
catch (ObjException)
{
// This sort of exception needs to pass through, since it indicates code is constructed incorrectly.
throw;
}
catch (Exception ex) {
topLevel.Output[$"{outName}-error"] = ex.Message;
// In this case, we don't know if the site is up or down,
// just that something went wrong
topLevel.Output[outName] = null;
return(false);
}
}
return(false);
};
return(topLevel);
}