import Toybox.Lang;
import Toybox.Math;
import Toybox.System;
import Toybox.Time;
import Toybox.Time.Gregorian;
import Toybox.Application;
import Toybox.ActivityMonitor;
import Toybox.Activity;
import Toybox.UserProfile;
import Toybox.SensorHistory;
import Toybox.Weather;
import Toybox.Position;
import Toybox.WatchUi;
import FieldTable;
import Settings;

// Everything a complication slot can show.  Ids match
// https://watchface.io/docs/datafields so the two catalogues line up; see
// tools/gen_fields.py for the table that drives the settings and the labels.
//
// Only fields Connect IQ can answer from the watch itself are here.  The
// week-to-date and 7/28-day per-sport aggregates in that catalogue come from a
// phone-side Garmin Connect integration, and the OpenWeatherMap / StormGlass /
// third-party-app fields need network calls and API keys; neither is something
// a self-contained watch face can produce.
module Fields {

    const DASH = "--";

    var mDow as Array<String>?;
    var mMon as Array<String>?;
    var mLabels as Array<String>?;
    var mMeridiem as Array<String>?;
    var mDateFmt as String = "$1$ $2$";

    function loadStrings() as Void {
        mDow = splitCsv(WatchUi.loadResource(Rez.Strings.DowNames) as String);
        mMon = splitCsv(WatchUi.loadResource(Rez.Strings.MonNames) as String);
        mLabels = splitCsv(WatchUi.loadResource(Rez.Strings.FieldLabels) as String);
        mMeridiem = splitCsv(WatchUi.loadResource(Rez.Strings.Meridiem) as String);
        mDateFmt = WatchUi.loadResource(Rez.Strings.DateFormat) as String;
    }

    function ready() as Boolean { return mDow != null; }

    // Monkey C has no String.split.
    function splitCsv(str as String) as Array<String> {
        var out = [] as Array<String>;
        var rest = str;
        var cut = rest.find(",");
        while (cut != null) {
            out.add(rest.substring(0, cut) as String);
            rest = rest.substring(cut + 1, rest.length()) as String;
            cut = rest.find(",");
        }
        out.add(rest);
        return out;
    }

    function dow(g as Gregorian.Info) as String {
        return mDow == null ? "" : mDow[g.day_of_week - 1];
    }

    function month(g as Gregorian.Info) as String {
        return mMon == null ? "" : mMon[g.month - 1];
    }

    function monthDay(g as Gregorian.Info) as String {
        return Lang.format(mDateFmt, [month(g), g.day.format("%d")]);
    }

    // "10" in English, "10日" in Chinese -- the format string carries the
    // suffix, so feed it an empty month.
    function dayOnly(g as Gregorian.Info) as String {
        return Lang.format(mDateFmt, ["", g.day.format("%d")]);
    }

    function meridiem(g as Gregorian.Info) as String {
        return mMeridiem == null ? "" : mMeridiem[g.hour >= 12 ? 1 : 0];
    }

    // Short caption printed under a bottom-row value.
    function label(id as Number) as String {
        if (mLabels == null) { return ""; }
        var i = FieldTable.indexOf(id);
        return i < mLabels.size() ? mLabels[i] : "";
    }

    // One of these is built per onUpdate and handed to every slot, so the
    // expensive lookups (forecast, sensor history, user profile) happen at most
    // once per draw and only if some slot actually asks for them.
    class Ctx {
        var greg as Gregorian.Info;
        var is24 as Boolean = true;
        var metric as Boolean = true;
        var fahrenheit as Boolean = false;

        private var mInfo as ActivityMonitor.Info?;
        private var mStats as System.Stats?;
        private var mDs as System.DeviceSettings?;
        private var mAct as Activity.Info?;
        private var mWx as Weather.CurrentConditions?;
        private var mFc as Array<Weather.DailyForecast>?;
        private var mProf as UserProfile.Profile?;
        private var mGotAct = false;
        private var mGotWx = false;
        private var mGotFc = false;
        private var mGotProf = false;

        function initialize(ds as System.DeviceSettings?, tempUnit as Number) {
            mDs = ds;
            greg = Gregorian.info(Time.now(), Time.FORMAT_SHORT);
            if (ds != null) {
                is24 = ds.is24Hour;
                metric = (ds.distanceUnits != System.UNIT_STATUTE);
                fahrenheit = (tempUnit == 2)
                    || (tempUnit == 0 && ds.temperatureUnits == System.UNIT_STATUTE);
            }
            if (tempUnit == 1) { fahrenheit = false; }
        }

        function ds() as System.DeviceSettings? { return mDs; }

        function info() as ActivityMonitor.Info? {
            if (mInfo == null) { mInfo = ActivityMonitor.getInfo(); }
            return mInfo;
        }

        function stats() as System.Stats? {
            if (mStats == null) { mStats = System.getSystemStats(); }
            return mStats;
        }

        function act() as Activity.Info? {
            if (!mGotAct) { mAct = Activity.getActivityInfo(); mGotAct = true; }
            return mAct;
        }

        function wx() as Weather.CurrentConditions? {
            if (!mGotWx) { mWx = Weather.getCurrentConditions(); mGotWx = true; }
            return mWx;
        }

        function forecast() as Weather.DailyForecast? {
            if (!mGotFc) { mFc = Weather.getDailyForecast(); mGotFc = true; }
            if (mFc != null && mFc.size() > 0) { return mFc[0]; }
            return null;
        }

        function profile() as UserProfile.Profile? {
            if (!mGotProf) { mProf = UserProfile.getProfile(); mGotProf = true; }
            return mProf;
        }

        function where() as Position.Location? {
            var w = wx();
            if (w != null && w.observationLocationPosition != null) {
                return w.observationLocationPosition;
            }
            var a = act();
            if (a != null && a.currentLocation != null) { return a.currentLocation; }
            return null;
        }
    }

    // ------------------------------------------------------------- helpers
    function num(v as Numeric?) as String {
        return v == null ? DASH : v.format("%d");
    }

    function one(v as Float?) as String {
        return v == null ? DASH : v.format("%.1f");
    }

    function clock(m as Time.Moment?, c as Ctx) as String {
        if (m == null) { return DASH; }
        return clockInfo(Gregorian.info(m, Time.FORMAT_SHORT), c);
    }

    function clockInfo(g as Gregorian.Info, c as Ctx) as String {
        var h = g.hour;
        if (!c.is24) {
            if (h == 0) { h = 12; } else if (h > 12) { h = h - 12; }
        }
        return h.format("%d") + ":" + g.min.format("%02d");
    }

    function offsetClock(minutes as Number, c as Ctx) as String {
        var m = Time.now().add(new Time.Duration(minutes * 60));
        return clock(m, c);
    }

    function temp(celsius as Numeric?, c as Ctx) as String {
        if (celsius == null) { return DASH; }
        var t = celsius.toFloat();
        if (c.fahrenheit) { t = t * 9.0 / 5.0 + 32.0; }
        return t.format("%d") + "°";
    }

    // ActivityMonitor distances are centimetres.
    function dist(cm as Numeric?, c as Ctx) as String {
        if (cm == null) { return DASH; }
        var km = cm.toFloat() / 100000.0;
        return (c.metric ? km : km * 0.621371).format("%.1f");
    }

    function metres(m as Numeric?, c as Ctx) as String {
        if (m == null) { return DASH; }
        var v = m.toFloat();
        return (c.metric ? v : v * 3.28084).format("%d");
    }

    function rounded(v as Numeric?) as String {
        if (v == null) { return DASH; }
        var n = v.toNumber();
        if (n < 1000) { return n.format("%d"); }
        return (n / 1000.0).format("%.1f") + "k";
    }

    // Newest reading out of a SensorHistory iterator, or null.
    function latest(iter) as Numeric? {
        if (iter == null) { return null; }
        var s = iter.next();
        if (s == null) { return null; }
        return s.data;
    }

    function dayOfYear(g as Gregorian.Info) as Number {
        var cum = [0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334];
        var d = cum[g.month - 1] + g.day;
        var y = g.year;
        var leap = (y % 4 == 0 && y % 100 != 0) || (y % 400 == 0);
        if (leap && g.month > 2) { d = d + 1; }
        return d;
    }

    // ISO 8601 week: weeks start Monday, week 1 holds the first Thursday.
    function isoWeek(g as Gregorian.Info) as Number {
        var dow = g.day_of_week - 1;          // 0 = Sunday
        var iso = dow == 0 ? 7 : dow;         // 1 = Monday .. 7 = Sunday
        var w = (dayOfYear(g) - iso + 10) / 7;
        if (w < 1) { return 52; }
        if (w > 52) { return 1; }
        return w;
    }

    // Days since the new moon of 2000-01-06, folded into one synodic month.
    function moonAge(g as Gregorian.Info) as Float {
        var y = g.year;
        var m = g.month;
        if (m <= 2) { y = y - 1; m = m + 12; }
        var a = y / 100;
        var b = 2 - a + a / 4;
        var jd = (365.25 * (y + 4716)).toNumber() + (30.6001 * (m + 1)).toNumber()
                 + g.day + b - 1524.5 + g.hour / 24.0;
        // Monkey C has no float modulo.
        var syn = 29.530588853;
        var x = jd - 2451550.1;
        var age = x - (x / syn).toNumber() * syn;
        if (age < 0) { age = age + syn; }
        return age.toFloat();
    }

    function windDir(bearingDeg as Numeric?) as String {
        if (bearingDeg == null) { return DASH; }
        var pts = ["N", "NNE", "NE", "ENE", "E", "ESE", "SE", "SSE",
                   "S", "SSW", "SW", "WSW", "W", "WNW", "NW", "NNW"];
        var b = bearingDeg.toFloat();
        while (b < 0) { b = b + 360.0; }
        var i = ((b + 11.25) / 22.5).toNumber() % 16;
        return pts[i];
    }

    // --------------------------------------------------------------- value
    // Clock, calendar and week-number fields.
    // Returns null when the id is not one of ours, so value()
    // can try the next category.
    function dateTime(id as Number, c as Ctx) as String? {
        if (id == 860) { return clockInfo(c.greg, c); }
        if (id == 880) {
            var utc = Gregorian.utcInfo(Time.now(), Time.FORMAT_SHORT);
            return clockInfo(utc, c);
        }
        if (id == 864) { return offsetClock(Settings.number("AltOffset1", 0), c); }
        if (id == 865) { return offsetClock(Settings.number("AltOffset2", 0), c); }
        if (id == 855) { return c.greg.day.format("%d"); }
        if (id == 868) { return c.greg.month.format("%d"); }
        if (id == 859) { return isoWeek(c.greg).format("%d"); }
        if (id == 873) { return ((dayOfYear(c.greg) + 6) / 7).format("%d"); }
        if (id == 870) { return dow(c.greg); }
        if (id == 856) { return dow(c.greg); }
        if (id == 853) { return month(c.greg); }
        if (id == 852) { return monthDay(c.greg); }
        if (id == 872) { return dow(c.greg) + " " + dayOnly(c.greg); }
        if (id == 851) { return dow(c.greg) + " " + monthDay(c.greg); }
        if (id == 858) { return meridiem(c.greg); }

        return null;
    }

    // Steps, calories, distance, floors and active minutes.
    // Returns null when the id is not one of ours, so value()
    // can try the next category.
    function activity(id as Number, c as Ctx) as String? {
        var i = c.info();
        if (id == 1)   { return i == null ? DASH : num(i.steps); }
        if (id == 14)  { return i == null ? DASH : rounded(i.steps); }
        if (id == 707) {
            if (i == null || i.steps == null || i.stepGoal == null) { return DASH; }
            var left = i.stepGoal - i.steps;
            return left > 0 ? left.format("%d") : "0";
        }
        if (id == 2)   { return i == null ? DASH : num(i.calories); }
        if (id == 603) {
            if (i == null || i.calories == null) { return DASH; }
            var p = c.profile();
            if (p == null || p.weight == null || p.height == null) { return num(i.calories); }
            return num(i.calories);          // device reports total only
        }
        if (id == 150 || id == 152 || id == 154) {
            if (i == null || !(i has :activeMinutesDay) || i.activeMinutesDay == null) {
                return DASH;
            }
            var am = i.activeMinutesDay;
            if (id == 152) { return num(am.moderate); }
            if (id == 154) { return num(am.vigorous); }
            return num(am.total);
        }
        if (id == 151) {
            if (i == null || !(i has :activeMinutesWeek) || i.activeMinutesWeek == null) {
                return DASH;
            }
            return num(i.activeMinutesWeek.total);
        }
        if (id == 3)   { return i == null ? DASH : dist(i.distance, c); }
        if (id == 4)   { return i == null ? DASH : num(i.floorsClimbed); }
        // Several ActivityMonitor.Info members compile everywhere but only
        // exist on some devices and firmware -- the wheelchair counters in
        // particular threw "Symbol Not Found" on a fenix 8.  Check before use.
        if (id == 5) {
            return (i == null || !(i has :floorsDescended)) ? DASH
                : num(i.floorsDescended);
        }
        if (id == 6) {
            return (i == null || !(i has :metersClimbed)) ? DASH
                : metres(i.metersClimbed, c);
        }
        if (id == 9) {
            return (i == null || !(i has :pushDistance)) ? DASH
                : dist(i.pushDistance, c);
        }
        if (id == 10) {
            return (i == null || !(i has :pushes)) ? DASH : num(i.pushes);
        }
        if (id == 8 || id == 15) {
            if (i == null || i.moveBarLevel == null) { return DASH; }
            var lvl = i.moveBarLevel;
            if (id == 15) { lvl = ActivityMonitor.MOVE_BAR_LEVEL_MAX - lvl; }
            return lvl.format("%d");
        }
        if (id == 13) {
            return (i == null || !(i has :timeToRecovery)) ? DASH
                : num(i.timeToRecovery);
        }
        if (id == 11) {
            return (i == null || !(i has :respirationRate)) ? DASH
                : num(i.respirationRate);
        }
        if (id == 12) {
            return (i == null || !(i has :stressScore)) ? DASH : num(i.stressScore);
        }

        return null;
    }

    // Heart, stress, oxygen, body battery and profile-derived values.
    // Returns null when the id is not one of ours, so value()
    // can try the next category.
    function body(id as Number, c as Ctx) as String? {
        if (id == 618) {
            var a = c.act();
            if (a != null && a.currentHeartRate != null) { return num(a.currentHeartRate); }
            var h = ActivityMonitor.getHeartRateHistory(1, true);
            if (h != null) {
                var s = h.next();
                if (s != null && s.heartRate != null
                        && s.heartRate != ActivityMonitor.INVALID_HR_SAMPLE) {
                    return num(s.heartRate);
                }
            }
            return DASH;
        }
        if (id == 276) {
            var p = c.profile();
            return (p == null || !(p has :restingHeartRate)) ? DASH
                : num(p.restingHeartRate);
        }
        if (id == 635) {
            if (!(SensorHistory has :getOxygenSaturationHistory)) { return DASH; }
            return num(latest(SensorHistory.getOxygenSaturationHistory({:period => 1})));
        }
        if (id == 623) {
            if (!(SensorHistory has :getBodyBatteryHistory)) { return DASH; }
            return num(latest(SensorHistory.getBodyBatteryHistory({:period => 1})));
        }
        if (id == 281 || id == 742) {
            var p = c.profile();
            if (p == null || !(p has :weight) || p.weight == null) { return DASH; }
            var kg = p.weight.toFloat() / 1000.0;
            if (id == 281) {
                return (c.metric ? kg : kg * 2.20462).format("%.1f");
            }
            if (!(p has :height) || p.height == null || p.height <= 0) { return DASH; }
            var m = p.height.toFloat() / 100.0;
            return (kg / (m * m)).format("%.1f");
        }
        if (id == 277 || id == 278) {
            var p = c.profile();
            if (p == null) { return DASH; }
            if (id == 278) {
                return (p has :vo2maxRunning) ? num(p.vo2maxRunning) : DASH;
            }
            return (p has :vo2maxCycling) ? num(p.vo2maxCycling) : DASH;
        }

        return null;
    }

    // Battery, alarms, notifications and radio state.
    // Returns null when the id is not one of ours, so value()
    // can try the next category.
    function system(id as Number, c as Ctx) as String? {
        var st = c.stats();
        if (id == 250) {
            return st == null || st.battery == null ? DASH
                : st.battery.format("%d") + "%";
        }
        if (id == 251) {
            if (st == null || !(st has :batteryInDays) || st.batteryInDays == null) {
                return DASH;
            }
            return st.batteryInDays.format("%d") + "d";
        }
        if (id == 257) {
            var pct = (st == null || st.battery == null) ? DASH : st.battery.format("%d");
            var d = (st == null || !(st has :batteryInDays) || st.batteryInDays == null)
                ? DASH : st.batteryInDays.format("%d");
            return pct + "/" + d;
        }
        if (id == 252) {
            if (st == null || !(st has :solarIntensity) || st.solarIntensity == null) {
                return DASH;
            }
            return st.solarIntensity.format("%d") + "%";
        }
        var ds = c.ds();
        if (id == 253) { return ds == null ? DASH : num(ds.alarmCount); }
        if (id == 255) { return ds == null ? DASH : num(ds.notificationCount); }
        if (id == 254) {
            return ds == null ? DASH : (ds.doNotDisturb ? "ON" : "OFF");
        }
        if (id == 256) {
            return ds == null ? DASH : (ds.phoneConnected ? "ON" : "OFF");
        }

        return null;
    }

    // Altitude, pressure, sun events and moon phase.
    // Returns null when the id is not one of ours, so value()
    // can try the next category.
    function environment(id as Number, c as Ctx) as String? {
        if (id == 615) {
            var a = c.act();
            return (a == null || !(a has :altitude)) ? DASH : metres(a.altitude, c);
        }
        if (id == 616 || id == 733) {
            var a = c.act();
            if (a == null) { return DASH; }
            var pa = null;
            if (id == 616 && (a has :meanSeaLevelPressure)) {
                pa = a.meanSeaLevelPressure;
            } else if (id == 733 && (a has :ambientPressure)) {
                pa = a.ambientPressure;
            }
            if (pa == null) { return DASH; }
            return (pa.toFloat() / 100.0).format("%d");
        }
        if (id == 712 || id == 717 || id == 700 || id == 731) {
            var loc = c.where();
            if (loc == null) { return DASH; }
            var now = Time.now();
            var rise = Weather.getSunrise(loc, now);
            var set = Weather.getSunset(loc, now);
            if (id == 712) { return clock(rise, c); }
            if (id == 717) { return clock(set, c); }
            if (rise == null || set == null) { return DASH; }
            var next = (now.compare(rise) < 0) ? rise
                     : ((now.compare(set) < 0) ? set : rise);
            if (id == 700) { return clock(next, c); }
            var secs = next.compare(now);
            if (secs < 0) { secs = secs + 86400; }
            return (secs / 3600).format("%d") + "h" + ((secs % 3600) / 60).format("%02d");
        }
        if (id == 706) { return moonAge(c.greg).format("%.1f"); }
        if (id == 732) {
            var age = moonAge(c.greg);
            var lit = (1.0 - Math.cos(2.0 * Math.PI * age / 29.530588853)) / 2.0;
            return (lit * 100.0).format("%d") + "%";
        }

        return null;
    }

    // Garmin's cached conditions and today's forecast.
    // Returns null when the id is not one of ours, so value()
    // can try the next category.
    function weather(id as Number, c as Ctx) as String? {
        var w = c.wx();
        if (id == 306) { return w == null ? DASH : temp(w.temperature, c); }
        if (id == 300) {
            return (w == null || !(w has :feelsLikeTemperature)) ? DASH
                : temp(w.feelsLikeTemperature, c);
        }
        if (id == 305) {
            return (w == null || !(w has :relativeHumidity)) ? DASH
                : num(w.relativeHumidity) + "%";
        }
        if (id == 304) {
            if (w == null || !(w has :precipitationChance)) { return DASH; }
            return num(w.precipitationChance) + "%";
        }
        if (id == 308) {
            if (w == null || !(w has :windSpeed) || w.windSpeed == null) { return DASH; }
            var kmh = w.windSpeed.toFloat() * 3.6;
            return (c.metric ? kmh : kmh * 0.621371).format("%d");
        }
        if (id == 307) {
            return (w == null || !(w has :windBearing)) ? DASH : num(w.windBearing);
        }
        if (id == 310) {
            return (w == null || !(w has :windBearing)) ? DASH : windDir(w.windBearing);
        }
        if (id == 309) {
            if (w == null || !(w has :observationTime) || w.observationTime == null) {
                return DASH;
            }
            return clock(w.observationTime, c);
        }
        if (id == 301 || id == 302 || id == 639) {
            var f = c.forecast();
            if (f == null) { return DASH; }
            var hi = (f has :highTemperature) ? f.highTemperature : null;
            var lo = (f has :lowTemperature) ? f.lowTemperature : null;
            if (id == 301) { return temp(hi, c); }
            if (id == 302) { return temp(lo, c); }
            return temp(hi, c) + "/" + temp(lo, c);
        }

        return null;
    }

    // Free text the wearer typed into the settings.
    // Returns null when the id is not one of ours, so value()
    // can try the next category.
    function custom(id as Number, c as Ctx) as String? {
        if (id == 703) { return Settings.text("Custom1"); }
        if (id == 704) { return Settings.text("Custom2"); }
        if (id == 705) { return Settings.text("Custom3"); }
        return null;
    }

    // Text for one data slot.  Categories are tried in turn rather
    // than dispatched on an id range, because the ids interleave.
    function value(id as Number, c as Ctx) as String {
        var v = dateTime(id, c);
        if (v == null) { v = activity(id, c); }
        if (v == null) { v = body(id, c); }
        if (v == null) { v = system(id, c); }
        if (v == null) { v = environment(id, c); }
        if (v == null) { v = weather(id, c); }
        if (v == null) { v = custom(id, c); }
        return v == null ? "" : v;
    }
}