OsmAnd zh_tts: get rid of "tenths of a mile" and other fixes

zh_tts.js

// IMPLEMENTED (X) or MISSING ( ) FEATURES, (N/A) if not needed in this language:
//
// (X) Basic navigation prompts: route (re)calculated (with distance and time support), turns, roundabouts, u-turns, straight/follow, arrival
// (X) Announce nearby point names (destination / intermediate / GPX waypoint / favorites / POI)
// (X) Attention prompts: SPEED_CAMERA; SPEED_LIMIT; BORDER_CONTROL; RAILWAY; TRAFFIC_CALMING; TOLL_BOOTH; STOP; PEDESTRIAN; MAXIMUM; TUNNEL
// (X) Other prompts: gps lost, off route, back to route
// (X) Street name and prepositions (onto / on / to) and street destination (toward) support
// (X) Distance unit support (meters / feet / yard)
// (N/A) Special grammar: (please specify which)
// (X) Support announcing highway exits

var metricConst;
var dictionary = {};
var tts = true;

function populateDictionary(tts) {
}

//// COMMAND BUILDING / WORD ORDER
////////////////////////////////////////////////////////////////
function setMetricConst(metrics) {
	metricConst = metrics;
}

function setMode(mode) {
	tts = true;
}

function route_new_calc(dist, timeVal) {
	return "行驶距离" + distance(dist) + "，预计用时" + time(timeVal) + "。";
}

function dist_to_str(dist, scale_down, scale_up) {
	return (Math.round(dist / scale_down) * scale_up).toString()
}

function distance(dist) {
	const meters = "米";
	const kilometers = "千米";
	const feet = "英尺";
	const miles = "英里";
	const yards = "码";
	const around = "大约";
	const _ft = 0.3048;
	const _mi = 1609.34;
	const _yd = 0.9144;
	switch (metricConst) {
		case "km-m":
			if (dist < 17)
				return dist_to_str(dist, 1.0, 1) + meters;
			if (dist < 100)
				return dist_to_str(dist, 10., 10) + meters;
			if (dist < 1000)
				return dist_to_str(dist, 50., 50) + meters;
			if (dist < 1500)
				return around + "1" + kilometers;
			if (dist < 10000)
				return around + dist_to_str(dist, 1000., 1) + kilometers;
			return dist_to_str(dist, 1000., 1) + kilometers;
		case "mi-f":
			if (dist < 17 * _ft)
				return dist_to_str(dist, 1.0*_ft, 1) + feet;
			if (dist < 100 * _ft)
				return dist_to_str(dist, 10.*_ft, 10) + feet;
			if (dist < 1000 * _ft)
				return dist_to_str(dist, 50.*_ft, 50) + feet;
			if (dist < .4 * _mi)
				return "1/4" + miles;
			if (dist < .6 * _mi)
				return "1/2" + miles;
			if (dist < .8 * _mi)
				return "3/4" + miles;
			if (dist < 1.5 * _mi)
				return around + "1" + miles;
			if (dist < 10 * _mi)
				return around + dist_to_str(dist, _mi, 1) + miles;
			return dist_to_str(dist, _mi, 1) + miles;
		case "mi-m":
			if (dist < 17)
				return dist_to_str(dist, 1.0, 1) + meters;
			if (dist < 100)
				return dist_to_str(dist, 10., 10) + meters;
			if (dist < 1000)
				return dist_to_str(dist, 50., 50) + meters;
			if (dist < .8 * _mi)
				return "3/4" + miles;
			if (dist < 1.5 * _mi)
				return around + "1" + miles;
			if (dist < 10 * _mi)
				return around + dist_to_str(dist, _mi, 1) + miles;
			return dist_to_str(dist, _mi, 1) + miles;
		case "mi-y":
			if (dist < 17)
				return dist_to_str(dist, _yd, 1) + yards;
			if (dist < 100)
				return dist_to_str(dist, 10*_yd, 10) + yards;
			if (dist < 1300)
				return dist_to_str(dist, 50*_yd, 50) + yards;
			if (dist < 10 * _mi)
				return around + dist_to_str(dist, _mi, 1) + miles;
			return dist_to_str(dist, _mi, 1) + miles;
	}
}

function time(seconds) {
	var minutes = Math.round(seconds/60.0);
	if (seconds < 30)
		return "小于1分钟";
	if (minutes % 60 == 0)
		return hours(minutes);
	return hours(minutes) + (minutes % 60) + "分钟";
}

function hours(minutes) {
	if (minutes < 60)
		return "";
	var hours = Math.floor(minutes / 60);
	return  hours.toString() + "小时"; 
}

function route_recalc(dist, seconds) {
	return "路线重新计算，" + route_new_calc(dist, seconds);
}

function go_ahead(dist, streetName) {
	var s = "向前行驶";
	if (dist != -1)
		s += distance(dist) + "，" + follow_street(streetName);
	return s;
}

function towards(dest) {
	return "前往" + dest;
}

function follow_street(streetName) {
	var toDest = streetName["toDest"];
	var toStreetName = streetName["toStreetName"];
	var toRef = streetName["toRef"];
	if ((toDest === "" && toStreetName === "" && toRef === "") || Object.keys(streetName).length == 0)
		return "";
	if (toStreetName === "" && toRef === "")
		return towards(toDest);
	var fromRef = streetName["fromRef"];
	var fromStreetName = streetName["fromStreetName"];
	if (toRef === fromRef && (toStreetName === fromStreetName ||
			toStreetName == ""))
		return "在" + assemble_street_name(streetName); // on
	return "到" + assemble_street_name(streetName); // to
}

function in_distance(dist, action) {
	if (dist == -1)
		return action;
	return distance(dist) + "后，" + action;
}

function turn(turnType, dist, streetName) {
	return in_distance(dist, getTurnType(turnType) + turn_street(streetName));
}

function take_exit(turnType, dist, exitString, exitInt, streetName) {
	return in_distance(dist,
		getTurnType(turnType) + "进入" + getExitNumber(exitString, exitInt) + take_exit_name(streetName));
}

function take_exit_name(streetName) {
	var toDest = streetName["toDest"];
	var toStreetName = streetName["toStreetName"];
	if (Object.keys(streetName).length == 0 || (toDest === "" && toStreetName === ""))
		return "";
	if (toDest != "")
		return "，" + toStreetName + towards(streetName["toDest"]);
	if (toStreetName != "")
		return "，" + toStreetName;
	return "";
}

function getExitNumber(exitString, exitInt) {
	return exitString + " 出口";
}

const _turnTypes = {
	"left": "左转",
	"left_sh": "向左急转",
	"left_sl": "稍向左转",
	"right": "右转",
	"right_sh": "向右急转",
	"right_sl": "稍向右转",
	"left_keep": "靠左行驶",
	"right_keep": "靠右行驶",
};
function  getTurnType(turnType) {
	return _turnTypes[turnType];
}

function then() {
	return "，然后";
}

function roundabout(dist, angle, exit, streetName) {
	var s = "在第" + exit + "个出口驶出，" + turn_street(streetName);
	if (dist != -1) {
		s = in_distance(dist, "进入环岛") + then() + s;
	}
	return s;
}

function turn_street(streetName) {
	var toDest = streetName["toDest"];
	var toStreetName = streetName["toStreetName"];
	var toRef = streetName["toRef"];
	if ((toDest === "" && toStreetName === "" && toRef === "") || Object.keys(streetName).length == 0)
		return "";
	if (toStreetName === "" && toRef === "")
		return towards(toDest);
	var fromRef = streetName["fromRef"];
	var fromStreetName = streetName["fromStreetName"];
	if (toRef === fromRef && (toStreetName === fromStreetName ||
		toStreetName === ""))
		return "到" + assemble_street_name(streetName);  // on
	return "到" + assemble_street_name(streetName);  // into
}

function assemble_street_name(streetName) {
	var toDest = streetName["toDest"];
	var toStreetName = streetName["toStreetName"];
	var toRef = streetName["toRef"];
	if (toDest === "")
		return toRef + " " + toStreetName;
	if (toRef === "")
		return toStreetName + towards(toDest);
	return toRef + towards(toDest);
}

function make_ut(dist, streetName) {
	return in_distance(dist, "调头，" + turn_street(streetName));
}

function bear_left(streetName) {
	return "靠左";
}

function bear_right(streetName) {
	return "靠右";
}

function after_distance(dist, action) {
	return "继续行驶" + distance(dist) + "，然后" + action;
}

function prepare_make_ut(dist, streetName) {
	return after_distance(dist, "调头，" + turn_street(streetName));
}

function prepare_turn(turnType, dist, streetName) {
	return after_distance(dist, getTurnType(turnType) + turn_street(streetName));
}

function prepare_roundabout(dist, exit, streetName) {
	return after_distance(dist, "将进入环岛");
}

function and_arrive_destination(dest) {
	return "并到达终点 " + dest;
}

function and_arrive_intermediate(dest) {
	return "并到达经停点 " + dest;
}

function and_arrive_waypoint(dest) {
	return "并到达GPX航路点 " + dest;
}

function and_arrive_favorite(dest) {
	return "并到达收藏点 " + dest;
}

function and_arrive_poi(dest) {
	return "并到达兴趣点 " + dest;
}

function reached_destination(dest) {
	return "已到达终点 " + dest;
}

function reached_waypoint(dest) {
	return "已到达GPX航路点 " + dest;
}

function reached_intermediate(dest) {
	return "已到达经停点 " + dest;
}

function reached_favorite(dest) {
	return "已到达收藏点 " + dest;
}

function reached_poi(dest) {
	return "已到达兴趣点 " + dest;
}

function location_lost() {
	return "GPS信号丢失";
}

function location_recovered() {
	return "GPS信号已恢复";
}

function off_route(dist) {
	return "您已偏离路线 " + distance(dist);
}

function back_on_route() {
	return "您已回到路线上";
}

function make_ut_wp() {
	return "条件允许时，调头";
}

// // TRAFFIC WARNINGS
function speed_alarm(maxSpeed, speed) {
	return "您已超速，限速" + maxSpeed.toString();
}

function attention(type) {
	return "注意，" + getAttentionString(type);
}

const _attentionString = {
	"SPEED_CAMERA": "测速拍照",
	"SPEED_LIMIT": "",
	"BORDER_CONTROL": "边境管理",
	"RAILWAY": "铁路道口",
	"TOLL_BOOTH": "收费站",
	"TRAFFIC_CALMING": "减速带",
	"STOP": "停止标志",
	"PEDESTRIAN": "人行横道",
	"MAXIMUM": "",
	"TUNNEL": "隧道",
};
function getAttentionString(type) {
	return _attentionString[type] || "";
}