//          Copyright Brian Schott (Hackerpilot) 2014.
// Distributed under the Boost Software License, Version 1.0.
//    (See accompanying file LICENSE_1_0.txt or copy at
//          http://www.boost.org/LICENSE_1_0.txt)

module analysis.undocumented;

import std.d.ast;
import std.d.lexer;
import analysis.base;

import std.regex : ctRegex, matchAll;
import std.stdio;

/**
 * Checks for undocumented public declarations. Ignores some operator overloads,
 * main functions, and functions whose name starts with "get" or "set".
 */
class UndocumentedDeclarationCheck : BaseAnalyzer
{
	alias visit = BaseAnalyzer.visit;

	this(string fileName)
	{
		super(fileName);
	}

	override void visit(const Module mod)
	{
		push(tok!"public");
		mod.accept(this);
	}

	override void visit(const Declaration dec)
	{
		if (dec.attributeDeclaration)
		{
			auto attr = dec.attributeDeclaration.attribute;
			if (isProtection(attr.attribute.type))
				set(attr.attribute.type);
			else if (attr.attribute == tok!"override")
				setOverride(true);
			else if (attr.deprecated_ !is null)
				setDeprecated(true);
			else if (attr.atAttribute !is null && attr.atAttribute.identifier.text == "disable")
				setDisabled(true);
		}

		immutable bool shouldPop = dec.attributeDeclaration is null;
		immutable bool prevOverride = getOverride();
		immutable bool prevDisabled = getDisabled();
		immutable bool prevDeprecated = getDeprecated();
		bool dis = false;
		bool dep = false;
		bool ovr = false;
		bool pushed = false;
		foreach (attribute; dec.attributes)
		{
			if (isProtection(attribute.attribute.type))
			{
				if (shouldPop)
				{
					pushed = true;
					push(attribute.attribute.type);
				}
				else
					set(attribute.attribute.type);
			}
			else if (attribute.attribute == tok!"override")
				ovr = true;
			else if (attribute.deprecated_ !is null)
				dep = true;
			else if (attribute.atAttribute !is null && attribute.atAttribute.identifier.text == "disable")
				dis = true;
		}
		if (ovr)
			setOverride(true);
		if (dis)
			setDisabled(true);
		if (dep)
			setDeprecated(true);
		dec.accept(this);
		if (shouldPop && pushed)
			pop();
		if (ovr)
			setOverride(prevOverride);
		if (dis)
			setDisabled(prevDisabled);
		if (dep)
			setDeprecated(prevDeprecated);
	}

	override void visit(const VariableDeclaration variable)
	{
		if (!currentIsInteresting() || variable.comment !is null)
			return;
		if (variable.autoDeclaration !is null)
		{
			addMessage(variable.autoDeclaration.identifiers[0].line,
				variable.autoDeclaration.identifiers[0].column,
				variable.autoDeclaration.identifiers[0].text);
			return;
		}
		foreach (dec; variable.declarators)
		{
			addMessage(dec.name.line, dec.name.column, dec.name.text);
			return;
		}
	}

	override void visit(const ConditionalDeclaration cond)
	{
		const VersionCondition ver = cond.compileCondition.versionCondition;
		if (ver is null || (ver.token != tok!"unittest" && ver.token.text != "none"))
			cond.accept(this);
		else if (cond.falseDeclaration !is null)
			visit(cond.falseDeclaration);
	}

	override void visit(const FunctionBody fb) {}
	override void visit(const Unittest u) {}
	override void visit(const TraitsExpression t) {}

	mixin V!ClassDeclaration;
	mixin V!InterfaceDeclaration;
	mixin V!StructDeclaration;
	mixin V!UnionDeclaration;
	mixin V!TemplateDeclaration;
	mixin V!FunctionDeclaration;
	mixin V!Constructor;

private:

	mixin template V(T)
	{
		override void visit(const T declaration)
		{
			import std.traits : hasMember;
			if (currentIsInteresting())
			{
				if (declaration.comment is null)
				{
					static if (hasMember!(T, "name"))
					{
						static if (is (T == FunctionDeclaration))
						{
							import std.algorithm : canFind;
							if (!(ignoredFunctionNames.canFind(declaration.name.text)
								|| isGetterOrSetter(declaration.name.text)
								|| isProperty(declaration)))
							{
								addMessage(declaration.name.line, declaration.name.column,
									declaration.name.text);
							}
						}
						else
						{
							if (declaration.name.type != tok!"")
								addMessage(declaration.name.line, declaration.name.column,
									declaration.name.text);
						}
					}
					else
					{
						addMessage(declaration.line, declaration.column, null);
					}
				}
				static if (!(is (T == TemplateDeclaration)
					|| is(T == FunctionDeclaration)))
				{
					declaration.accept(this);
				}
			}
		}
	}

	static bool isGetterOrSetter(string name)
	{
		return !matchAll(name, getSetRe).empty;
	}

	static bool isProperty(const FunctionDeclaration dec)
	{
		if (dec.memberFunctionAttributes is null)
			return false;
		foreach (attr; dec.memberFunctionAttributes)
		{
			if (attr.atAttribute && attr.atAttribute.identifier.text == "property")
				return true;
		}
		return false;
	}

	void addMessage(size_t line, size_t column, string name)
	{
		import std.string : format;
		addErrorMessage(line, column, "dscanner.style.undocumented_declaration",
			name is null ? "Public declaration is undocumented." :
				format("Public declaration '%s' is undocumented.", name));
	}

	bool getOverride()
	{
		return stack[$ - 1].isOverride;
	}

	void setOverride(bool o = true)
	{
		stack[$ - 1].isOverride = o;
	}

	bool getDisabled()
	{
		return stack[$ - 1].isDisabled;
	}

	void setDisabled(bool d = true)
	{
		stack[$ - 1].isDisabled = d;
	}

	bool getDeprecated()
	{
		return stack[$ - 1].isDeprecated;
	}

	void setDeprecated(bool d = true)
	{
		stack[$ - 1].isDeprecated = d;
	}

	bool currentIsInteresting()
	{
		return stack[$ - 1].protection == tok!"public" && !stack[$ - 1].isOverride
			&& !stack[$ - 1].isDisabled && !stack[$ - 1].isDeprecated;
	}

	void set(IdType p)
	in { assert (isProtection(p)); }
	body
	{
		stack[$ - 1].protection = p;
	}

	void push(IdType p)
	in { assert (isProtection(p)); }
	body
	{
		stack ~= ProtectionInfo(p, false);
	}

	void pop()
	{
		assert (stack.length > 1);
		stack = stack[0 .. $ - 1];
	}

	static struct ProtectionInfo
	{
		IdType protection;
		bool isOverride;
		bool isDeprecated;
		bool isDisabled;
	}

	ProtectionInfo[] stack;
}

// Ignore undocumented symbols with these names
private immutable string[] ignoredFunctionNames = [
	"opCmp",
	"opEquals",
	"toString",
	"toHash",
	"main"
];

private enum getSetRe = ctRegex!`^(?:get|set)(?:\p{Lu}|_).*`;