#include "app.h"

#include <array>
#include <cstdio>
#include <future>

#include <curses.h>

#include "build_config.h"
#include "util.h"

namespace telegram_tui {

namespace {

std::string trim_release_tag_prefix(const std::string &value) {
	if (!value.empty() && (value[0] == 'v' || value[0] == 'V')) {
		return value.substr(1);
	}
	return value;
}

bool is_truthy_env_value(const std::string &value) {
	return value == "1" || value == "true" || value == "TRUE" || value == "yes" ||
	       value == "YES" || value == "on" || value == "ON";
}

std::string shell_quote(const std::string &value) {
	std::string quoted = "'";
	for (char ch : value) {
		if (ch == '\'') {
			quoted += "'\\''";
		} else {
			quoted.push_back(ch);
		}
	}
	quoted.push_back('\'');
	return quoted;
}

std::string run_command_capture(const std::string &command) {
	FILE *pipe = popen(command.c_str(), "r");
	if (pipe == nullptr) {
		return {};
	}

	std::string output;
	std::array<char, 4096> buffer{};
	while (std::fgets(buffer.data(), static_cast<int>(buffer.size()), pipe) != nullptr) {
		output += buffer.data();
	}
	if (pclose(pipe) != 0) {
		return {};
	}
	return output;
}

std::optional<std::string> fetch_update_notice() {
	static constexpr const char *kLatestReleaseApiUrl =
	        "https://git.mshq.dev/api/v1/repos/AxiFisk/shinoa/releases/latest";

	if (std::string(TELEGRAM_TUI_BUILD_COMMIT).empty()) {
		return std::nullopt;
	}

	const std::string response =
	        run_command_capture("curl -fsSL " + shell_quote(kLatestReleaseApiUrl) + " 2>/dev/null");
	if (response.empty()) {
		return std::nullopt;
	}

	try {
		const json release = json::parse(response, nullptr, true, true);
		const std::string latest_tag = trim_release_tag_prefix(safe_string(release, "tag_name"));
		if (!latest_tag.empty() && latest_tag == TELEGRAM_TUI_PROJECT_VERSION) {
			return std::nullopt;
		}

		const std::string target_commit = safe_string(release, "target_commitish");
		if (target_commit.empty()) {
			return std::nullopt;
		}
		const std::string current_commit = TELEGRAM_TUI_BUILD_COMMIT;
		if (target_commit == current_commit || target_commit.rfind(current_commit, 0) == 0) {
			return std::nullopt;
		}
		return std::string("Update available");
	} catch (const json::exception &) {
		return std::nullopt;
	}
}

} // namespace

App::App() {
	const StoredConfig config = load_app_config();
	api_id_ = get_env("TELEGRAM_API_ID");
	api_hash_ = get_env("TELEGRAM_API_HASH");
	if (api_id_.empty()) {
		api_id_ = TELEGRAM_TUI_BUILD_API_ID;
	}
	if (api_hash_.empty()) {
		api_hash_ = TELEGRAM_TUI_BUILD_API_HASH;
	}
	if (api_id_.empty()) {
		api_id_ = config.api_id;
	}
	if (api_hash_.empty()) {
		api_hash_ = config.api_hash;
	}
	auto_reload_chat_history_ = config.auto_reload_chat_history;
	phone_number_ = get_env("TELEGRAM_PHONE");
	use_test_dc_ = is_truthy_env_value(get_env("TELEGRAM_USE_TEST_DC"));

	const auto root = data_root();
	const auto state_root = use_test_dc_ ? (root / "test") : root;
	database_dir_ = state_root / "tdlib";
	files_dir_ = state_root / "files";
	std::filesystem::create_directories(database_dir_);
	std::filesystem::create_directories(files_dir_);
	if (!api_id_.empty() || !api_hash_.empty()) {
		persist_config();
	}

	if (use_test_dc_) {
		status_line_ = "Starting TDLib in test DC mode...";
	}

	start_update_check();
}

int App::run() {
	init_curses();
	draw();
	while (running_) {
		bool should_draw = process_updates();
		if (advance_attachment_animation()) {
			should_draw = true;
		}
		wint_t ch = 0;
		const int result = get_wch(&ch);
		if (result == KEY_CODE_YES) {
			handle_key(static_cast<int>(ch));
			should_draw = true;
		} else if (result == OK) {
			if (ch < 128) {
				handle_key(static_cast<int>(ch));
			} else {
				handle_wide_char(ch);
			}
			should_draw = true;
		}
		if (should_draw) {
			draw();
		}
	}
	shutdown_curses();
	return 0;
}

void App::start_update_check() {
	update_check_future_ =
	        std::async(std::launch::async, []() { return fetch_update_notice(); });
}

bool App::refresh_update_check_result() {
	if (!update_check_future_.valid()) {
		return false;
	}
	if (update_check_future_.wait_for(std::chrono::seconds(0)) != std::future_status::ready) {
		return false;
	}

	const auto notice = update_check_future_.get();
	if (notice == update_notice_) {
		return false;
	}
	update_notice_ = notice.value_or(std::string());
	return true;
}

std::optional<std::int64_t> App::highlighted_chat_id() const {
	if (sorted_chat_ids_.empty()) {
		return std::nullopt;
	}
	if (selected_chat_index_ < 0 ||
	    selected_chat_index_ >= static_cast<int>(sorted_chat_ids_.size())) {
		return std::nullopt;
	}
	return sorted_chat_ids_[selected_chat_index_];
}

std::optional<std::int64_t> App::open_chat_id() const {
	if (open_chat_id_ == 0) {
		return std::nullopt;
	}
	return open_chat_id_;
}

std::optional<std::size_t> App::find_message_index(const ChatInfo &chat,
                                                   std::int64_t message_id) const {
	for (std::size_t i = 0; i < chat.messages.size(); ++i) {
		if (chat.messages[i].id == message_id) {
			return i;
		}
	}
	return std::nullopt;
}

std::string App::format_message_ref(const ChatInfo &chat, std::int64_t message_id) const {
	const auto index = find_message_index(chat, message_id);
	if (index.has_value()) {
		return "[" + std::to_string(*index + 1) + "]";
	}
	return "#" + std::to_string(message_id);
}

} // namespace telegram_tui