#include "common.h"
#include "files.h"

namespace files {
	static FILE *handleFps[0x10000];

	static void *stdinHandle;
	static void *stdoutHandle;
	static void *stderrHandle;

	std::filesystem::path pathFromWindows(const char *inStr) {
		// Convert to forward slashes
		std::string str = inStr;
		std::replace(str.begin(), str.end(), '\\', '/');

		// Remove the drive letter
		if (str.starts_with("c:/") || str.starts_with("C:/")) {
			str.erase(0, 2);
		}

		// Return as-is if it exists, else traverse the filesystem looking for
		// a path that matches case insensitively
		std::filesystem::path path = std::filesystem::path(str);
		if (std::filesystem::exists(path)) {
			return path;
		}

		path = path.lexically_normal();
		std::filesystem::path newPath = ".";
		bool followingExisting = true;
		for (auto component : path) {
			std::filesystem::path newPath2 = newPath / component;
			if (followingExisting && !std::filesystem::exists(newPath2) && (component != ".." && component != "." && component != "")) {
				followingExisting = false;
				try {
					for (std::filesystem::path entry : std::filesystem::directory_iterator{newPath}) {
						if (strcasecmp(entry.filename().c_str(), component.c_str()) == 0) {
							followingExisting = true;
							newPath2 = entry;
							break;
						}
					}
				} catch (const std::filesystem::filesystem_error&) {
					// not a directory
				}
			}
			newPath = newPath2;
		}
		if (followingExisting) {
			DEBUG_LOG("Resolved case-insensitive path: %s\n", newPath.c_str());
		} else {
			DEBUG_LOG("Failed to resolve path: %s\n", newPath.c_str());
		}

		return newPath;
	}

	std::string pathToWindows(const std::filesystem::path &path) {
		std::string str = path;

		if (path.is_absolute()) {
			str.insert(0, "C:");
		}

		std::replace(str.begin(), str.end(), '/', '\\');
		return str;
	}

	FILE *fpFromHandle(void *handle, bool pop) {
		uintptr_t index = (uintptr_t)handle;
		if (index > 0 && index < 0x10000) {
			FILE *ret = handleFps[index];
			if (pop)
				handleFps[index] = 0;
			return ret;
		}
		if (pop)
			return 0;
		printf("Invalid file handle %p\n", handle);
		assert(0);
	}

	void *allocFpHandle(FILE *fp) {
		for (int i = 1; i < 0x10000; i++) {
			if (!handleFps[i]) {
				handleFps[i] = fp;
				return (void*)i;
			}
		}
		printf("Out of file handles\n");
		assert(0);
	}

	void *getStdHandle(uint32_t nStdHandle) {
		switch (nStdHandle) {
			case ((uint32_t) -10): // STD_INPUT_HANDLE
				return stdinHandle;
			case ((uint32_t) -11): // STD_OUTPUT_HANDLE
				return stdoutHandle;
			case ((uint32_t) -12): // STD_ERROR_HANDLE
				return stderrHandle;
			default:
				return (void *) 0xFFFFFFFF;
		}
	}

	unsigned int setStdHandle(uint32_t nStdHandle, void *hHandle) {
		FILE *fp = fpFromHandle(hHandle);
		assert(fp);
		switch (nStdHandle) {
			case ((uint32_t) -10): // STD_INPUT_HANDLE
				stdinHandle = hHandle;
				break;
			case ((uint32_t) -11): // STD_OUTPUT_HANDLE
				stdoutHandle = hHandle;
				break;
			case ((uint32_t) -12): // STD_ERROR_HANDLE
				stderrHandle = hHandle;
				break;
			default:
				return 0; // fail
		}
		return 1; // success
	}

	void init() {
		stdinHandle = allocFpHandle(stdin);
		stdoutHandle = allocFpHandle(stdout);
		stderrHandle = allocFpHandle(stderr);
	}
}