// Copyright (c) 2014-2016 Thomas Fussell
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, WRISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE
//
// @license: http://www.opensource.org/licenses/mit-license.php
// @author: see AUTHORS file
#include <fstream>
#include <sstream>
#include <sys/stat.h>

#ifdef __APPLE__
#include <mach-o/dyld.h>
#elif defined(__linux)
#include <unistd.h>
#include <linux/limits.h>
#include <sys/types.h>
#endif

#include <detail/include_windows.hpp>
#include <xlnt/utils/path.hpp>

namespace {

#ifdef WIN32

char system_separator()
{
	return '\\';
}

bool is_drive_letter(char letter)
{
	return letter >= 'A' && letter <= 'Z';
}

bool is_root(const std::string &part)
{
	if (part.size() == 1 && part[0] == '/') return true;
	if (part.size() != 3) return false;

	return is_drive_letter(part[0]) && part[1] == ':'
		&& (part[2] == '\\' || part[2] == '/');
}

bool is_absolute(const std::string &part)
{
	if (!part.empty() && part[0] == '/') return true;
	if (part.size() < 3) return false;

	return is_root(part.substr(0, 3));
}

#else

char system_separator()
{
	return '/';
}

bool is_root(const std::string &part)
{
	return part == "/";
}


bool is_absolute(const std::string &part)
{
    return !part.empty() && part[0] == '/';
}

#endif

std::vector<std::string> split_path(const std::string &path, char delim)
{
	std::vector<std::string> split;
	std::string::size_type previous_index = 0;
	auto separator_index = path.find(delim);

	while (separator_index != std::string::npos)
	{
		auto part = path.substr(previous_index, separator_index - previous_index);
		split.push_back(part);

		previous_index = separator_index + 1;
		separator_index = path.find(delim, previous_index);
	}	

	// Don't add trailing slash
	if (previous_index < path.size())
	{
		split.push_back(path.substr(previous_index));
	}

	return split;
}

bool file_exists(const std::string &path)
{
	struct stat info;
	return stat(path.c_str(), &info) == 0 && (info.st_mode & S_IFREG);
}

bool directory_exists(const std::string path)
{
	struct stat info;
	return stat(path.c_str(), &info) == 0 && (info.st_mode & S_IFDIR);
}

} // namespace

namespace xlnt {

char path::system_separator()
{
	return ::system_separator();
}

path::path()
{
}

path::path(const std::string &path_string) : internal_(path_string)
{
}

// general attributes 

bool path::is_relative() const
{
	return !is_absolute();
}

bool path::is_absolute() const
{
	return ::is_absolute(internal_);
}

bool path::is_root() const
{
    return ::is_root(internal_);
}

path path::parent() const
{
    if (is_root()) return *this;

    auto split_path = split();
    
    split_path.pop_back();
    
    if (split_path.empty())
    {
        return path("");
    }
    
    path result;
    
    for (const auto &component : split_path)
    {
        result = result.append(component);
    }
    
	return result;
}

std::string path::filename() const
{
    auto split_path = split();
	return split_path.empty() ? "" : split_path.back();
}

std::string path::extension() const
{
	auto base = filename();
	auto last_dot = base.find_last_of('.');
	
	return last_dot == std::string::npos ? "" : base.substr(last_dot + 1);
}

std::pair<std::string, std::string> path::split_extension() const
{
	auto base = filename();
	auto last_dot = base.find_last_of('.');

	return{ base.substr(0, last_dot), base.substr(last_dot + 1) };
}

// conversion

std::string path::string() const
{
    return internal_;
}

std::vector<std::string> path::split() const
{
    return split_path(internal_, guess_separator());
}

path path::resolve(const path &base_path) const
{
	if (is_absolute())
	{
		return *this;
	}

	path copy(base_path.internal_);

	for (const auto &part : split())
	{
        copy = copy.append(part);
	}
    
    return copy;
}

// filesystem attributes

bool path::exists() const
{
	return is_file() || is_directory();
}

bool path::is_directory() const
{
	return directory_exists(string());
}

bool path::is_file() const
{
	return file_exists(string());
}

// filesystem

std::string path::read_contents() const
{
	std::ifstream f(string());
	std::ostringstream ss;
	ss << f.rdbuf();

	return ss.str();
}

// append

path path::append(const std::string &to_append) const
{
    path copy(internal_);
    
    if (!internal_.empty() && internal_.back() != guess_separator())
    {
        copy.internal_.push_back(guess_separator());
    }
    
    copy.internal_.append(to_append);
    
    return copy;
}

path path::append(const path &to_append) const
{
	path copy(internal_);

	for (const auto &component : to_append.split())
	{
		copy = copy.append(component);
	}

	return copy;
}

char path::guess_separator() const
{
    if (system_separator() == '/' || internal_.empty() || internal_.front() == '/') return '/';
    if (is_absolute()) return internal_.at(2);
    return internal_.find('\\') != std::string::npos ? '\\' : '/';
}

path path::relative_to(const path &base_path) const
{
    if (is_relative()) return *this;

    auto base_split = base_path.split();
    auto this_split = split();
    auto index = std::size_t(0);

    while (index < base_split.size() && index < this_split.size() && base_split[index] == this_split[index])
    {
        index++;
    }

    auto result = path();

    for (auto i = index; i < this_split.size(); i++)
    {
        result = result.append(this_split[i]);
    }

    return result;
}

bool operator==(const path &left, const path &right)
{
    return left.internal_ == right.internal_;
}

} // namespace xlnt