import datetime
import json
import logging
import math
import time

from flask import (Flask, request, jsonify, abort, render_template_string, render_template)
from markupsafe import Markup

from ltsdb_json import LTS

log = logging.getLogger(__name__)

class Dashboard:
    def __init__(self, filename="dashboard.json"):
        with open (filename) as fh:
            d = json.load(fh)
        self.title = d["title"]
        log.debug("title = “%s”", self.title)
        self.description = d["description"]
        self.widgets = []
        for w in d["widgets"]:
            if w["type"] == "timeseries":
                # XXX - currently just a copy of the gauge code,
                # but I want to add support for timeseries graphs with 
                # multiple series later so this will change
                if w.get("multi"):
                    ts_list = LTS.find(w["data"][0])
                    for ts in ts_list:
                        tso = LTS(id=ts)
                        if not tso.data:
                            log.warning("%s has no data: Skipping", tso.id)
                            continue
                        if tso.data[-1][0] < time.time() - 86400:
                            log.info("%s too old; Skipping", tso.id)
                            continue
                        w1 = {**w, "data": [ts]}
                        self.widgets.append(TimeSeries(w1))
                else:
                    self.widgets.append(TimeSeries(w))
            elif  w["type"] == "gauge":
                if w.get("multi"):
                    ts_list = LTS.find(w["data"][0])
                    for ts in ts_list:
                        tso = LTS(id=ts)
                        if not tso.data:
                            log.warning("%s has no data: Skipping", tso.id)
                            continue
                        if tso.data[-1][0] < time.time() - 86400:
                            log.info("%s too old; Skipping", tso.id)
                            continue
                        w1 = {**w, "data": [ts]}
                        self.widgets.append(Gauge(w1))
                else:
                    self.widgets.append(Gauge(w))
            else:
                self.widgets.append(Widget(w))

    def as_html(self):
        return render_template("dashboard.html", dashboard=self)



class Widget:
    def __init__(self, d):
        self.type = d["type"]
        self.stops = d["stops"]
        log.debug("data = %s", d["data"])
        self.lts = LTS(id=d["data"][0]) # by default we handle only one data source
        pass

    def as_html(self):
        log.debug("")
        self.lastvalue = self.lts.data[-1][1]
        return Markup(render_template("widget.html", widget=self))

    @property
    def criticalcolor(self):
        log.debug("stops = %s", self.stops)
        brightness = 30
        if self.stops[0] < self.stops[2]:
            if self.lastvalue < self.stops[0]:
                log.debug("definitely ok")
                return f"hsl(120, 100%, {brightness}%)"
            elif self.lastvalue < self.stops[1]:
                log.debug("mostly ok")
                hue = 120 - round(
                                (self.lastvalue - self.stops[0])
                              / (self.stops[1] - self.stops[0])
                              * 60
                            )
                return f"hsl({hue}, 100%, {brightness}%)"
            elif self.lastvalue < self.stops[2]:
                log.debug("maybe fail")
                hue =  60 - round(
                                (self.lastvalue - self.stops[1])
                              / (self.stops[2] - self.stops[1])
                              * 60
                            )
                return f"hsl({hue}, 100%, {brightness}%)"
            else:
                log.debug("definitely fail")
                return f"hsl(0, 100%, {brightness}%)"
        else:
            log.debug("the other side")
            if self.lastvalue > self.stops[0]:
                log.debug("definitely ok")
                return f"hsl(120, 100%, {brightness}%)"
            elif self.lastvalue > self.stops[1]:
                log.debug("mostly ok")
                hue = 120 - round(
                                (self.lastvalue - self.stops[0])
                              / (self.stops[1] - self.stops[0])
                              * 60
                            )
                return f"hsl({hue}, 100%, {brightness}%)"
            elif self.lastvalue > self.stops[2]:
                log.debug("maybe fail")
                hue =  60 - round(
                                (self.lastvalue - self.stops[1])
                              / (self.stops[2] - self.stops[1])
                              * 60
                            )
                return f"hsl({hue}, 100%, {brightness}%)"
            else:
                log.debug("definitely fail")
                return f"hsl(0, 100%, {brightness}%)"


class TimeSeries(Widget):
    def __init__(self, d):
        super().__init__(d)
        pass

    def as_html(self):
        def t2x(t):
            x = n - math.log((t_last - t) / (n*dt) + 1) * n / k
            return x

        data = self.lts.data
        n = len(data)
        t_last = data[-1][0]
        dt = (t_last - data[-5][0]) / 4
        k = math.log((t_last - data[0][0]) / dt / n + 1)

        max_value = max([d[1] for d in self.lts.data])
        max_value = max(max_value, 0.001) # ensure positive
        v_data = []
        for i in range(n):
            t = data[i][0]
            x = t2x(t)
            t_h = time.strftime("%Y-%m-%d %H:%M:%S", time.localtime(t))
            #print(t, t_h, x)
            v_data.append({"t": t, "v": data[i][1], "x": x, "y": (1 - data[i][1]/max_value) * 200})

        tickmarks = []
        t = v_data[-1]["t"]
        x = v_data[-1]["x"]
        d = datetime.datetime.fromtimestamp(t)
        tickmarks.append({"t": t, "t_h": d.strftime("%Y-%m-%d %H:%M:%S"), "x": x})

        steps = ("s", "m", "h", "D", "M", "Y")
        step_i = 0
        while True:
            t0 = tickmarks[-1]["t"]
            x0 = tickmarks[-1]["x"]
            d0 = datetime.datetime.fromtimestamp(t0)

            if steps[step_i] == "s":
                d1 = datetime.datetime(d0.year, d0.month, d0.day, d0.hour, d0.minute, d0.second)
                t1 = d1.timestamp()
                x1 = t2x(t1)
                if x0 - x1 < 20:
                    d1 -= datetime.timedelta(seconds=1)
                    t1 = d1.timestamp()
                    x1 = t2x(t1)
                    if x0 - x1 < 20:
                        step_i += 1
                        continue

            if steps[step_i] == "m":
                d1 = datetime.datetime(d0.year, d0.month, d0.day, d0.hour, d0.minute)
                t1 = d1.timestamp()
                x1 = t2x(t1)
                if x0 - x1 < 20:
                    d1 -= datetime.timedelta(minutes=1)
                    t1 = d1.timestamp()
                    x1 = t2x(t1)
                    if x0 - x1 < 20:
                        step_i += 1
                        continue

            if steps[step_i] == "h":
                d1 = datetime.datetime(d0.year, d0.month, d0.day, d0.hour)
                t1 = d1.timestamp()
                x1 = t2x(t1)
                if x0 - x1 < 20:
                    d1 -= datetime.timedelta(hours=1)
                    t1 = d1.timestamp()
                    x1 = t2x(t1)
                    if x0 - x1 < 20:
                        step_i += 1
                        continue

            if steps[step_i] == "D":
                d1 = datetime.datetime(d0.year, d0.month, d0.day)
                t1 = d1.timestamp()
                x1 = t2x(t1)
                if x0 - x1 < 20:
                    d1 -= datetime.timedelta(days=1)
                    t1 = d1.timestamp()
                    x1 = t2x(t1)
                    if x0 - x1 < 20:
                        step_i += 1
                        continue

            if steps[step_i] == "M":
                d1 = datetime.datetime(d0.year, d0.month, 1)
                t1 = d1.timestamp()
                x1 = t2x(t1)
                if x0 - x1 < 20:
                    if d1.month > 1:
                        d1 = datetime.datetime(d1.year, d1.month-1, 1)
                    else:
                        d1 = datetime.datetime(d1.year-1, 12, 1)
                    t1 = d1.timestamp()
                    x1 = t2x(t1)
                    if x0 - x1 < 20:
                        step_i += 1
                        continue

            if steps[step_i] == "Y":
                d1 = datetime.datetime(d0.year, 1, 1)
                t1 = d1.timestamp()
                x1 = t2x(t1)
                if x0 - x1 < 20:
                    d1 = datetime.datetime(d1.year-1, 1, 1)
                    t1 = d1.timestamp()
                    x1 = t2x(t1)
                    if x0 - x1 < 20:
                        step_i += 1
                        continue
            if x1 < 0:
                break
            tickmarks.append({"t": t1, "t_h": d1.strftime("%Y-%m-%d %H:%M:%S"), "x": x1})
        if tickmarks[-1]["x"] > 20:
            t = v_data[0]["t"]
            x = v_data[0]["x"]
            d = datetime.datetime.fromtimestamp(t)
            tickmarks.append({"t": t, "t_h": d.strftime("%Y-%m-%d %H:%M:%S"), "x": x})
        self.x_tickmarks = tickmarks

        self.y_tickmarks = []
        step = 10 ** math.floor(math.log10(max_value))
        v = 0
        while v < max_value:
            self.y_tickmarks.append({"y": (1 - v/max_value) * 200, "v_h": str(v)})
            v += step

        html = ""
        html += "<svg width=1200 height=300>"
        for tm in self.x_tickmarks:
            html += f"<line x1={tm['x']} y1=0 x2={tm['x']} y2=200 stroke='#CCC' />"
            html += f"<text transform='translate({tm['x']}, 210) rotate(30)' fill='#888'>{tm['t_h']}</text>"
        for tm in self.y_tickmarks:
            html += f"<line x1=0 y1={tm['y']} x2=1000 y2={tm['y']} stroke='#CCC' />"
            html += f"<text x=1005 y={tm['y']} fill='#888'>{tm['v_h']}</text>"
        for v in v_data:
            html += f"<circle cx={v['x']} cy={v['y']} r=3 fill='#00F' />"
        html += "</svg>"
        return Markup(html)

class Gauge(Widget):
    def __init__(self, d):
        super().__init__(d)
        pass

    gaugesize = 100

    @property
    def gaugepos(self):
        max_value = max([d[1] for d in self.lts.data])
        max_value = max(max_value, 1) # ensure positive
        log.debug("max_value = %s", max_value)
        return self.lastvalue / max_value * self.gaugesize

    def as_html(self):
        log.debug("")
        self.lastvalue = self.lts.data[-1][1]
        value = self.lastvalue
        unit = self.lts.description["unit"]
        log.debug("unit = %s", unit)
        if unit == "s":
            if value >= 365.25 * 86400:
                value /= 365.25 * 86400
                unit = "years"
            elif value >= 86400:
                value /= 86400
                unit = "days"
            elif value >= 3600:
                value /= 3600
                unit = "h"
            elif value >= 60:
                value /= 60
                unit = "m"
            elif value >= 1:
                pass
            elif value >= 0.001:
                value *= 1000
                unit = "ms"
        self.lastvalue_formatted = Markup(f"<span class='value'>{value:.2f}</span><span class='unit'>{unit}</unit>")
        return Markup(render_template("gauge.html", widget=self))

    @property
    def description_formatted(self):
        s = "<table class='description'>"
        for d, v in self.lts.description.items():
            if v:
                s += render_template_string(
                        "<tr><th>{{d}}:</th><td>{{v}}</td></tr>",
                        d=d, v=v)
        s += "</table>"
        return Markup(s)