import fcntl
import hmac
import json
import logging
import os

from flask import (Flask, request, jsonify, abort, render_template)

from ltsdb_json import LTS

logging.basicConfig(level=logging.DEBUG)

app = Flask(__name__)

log = logging.getLogger()

@app.route("/")
def home():
    return jsonify({ "success": None })


@app.route("/report", methods=["POST"])
def report():
    data = request.get_json()
    n_ts = 0
    n_dp = 0
    for d in data:
        d["description"]["remote_addr"] = request.remote_addr
        d["description"]["node"] = verify_node(d)

        log.info("received %s", json.dumps(d))
        ts = LTS(d["description"])
        for dp in d["data"]:
            ts.add(*dp)
            ts.save()
            n_dp += 1
        n_ts += 1
    return jsonify({ "success": True, "timeseries": n_ts, "datapoints": n_dp })

@app.route("/ts/<id>")
def get_timeseries(id):
    try:
        ts = LTS(id=id)
    except FileNotFoundError:
        abort(404)
    return jsonify({"description": ts.description, "data": ts.data})

@app.route("/dimensions")
def list_dimensions():
    with open("data/.index") as fh:
        fcntl.flock(fh, fcntl.LOCK_SH)
        index = json.load(fh)
    # Just return the number of timeseries for each dimension/member, not
    # the timeseries themselves
    for d in index.keys():
        for m in index[d].keys():
            index[d][m] = len(index[d][m])
    return jsonify(index)

@app.route("/search")
def search():
    log.debug("search: %s", request.args)
    timeseries = None
    with open("data/.index") as fh:
        fcntl.flock(fh, fcntl.LOCK_SH)
        index = json.load(fh)
    for k, v in request.args.lists():
        log.debug("search: %s -> %s", k, v)
        if timeseries == None:
            timeseries = set()
            log.debug("search: %s: %s", k, index[k])
            for m in v:
                timeseries |= set(index[k][m])
        else:
            filter = set()
            for m in v:
                filter |= set(index[k][m])
            timeseries &= filter
    results = list(timeseries)
    return jsonify(results)


def verify_node(d):
    node = d["auth"]["node"]
    timestamp = d["auth"]["timestamp"]
    digest1 = d["auth"]["hmac"]
    if "/" in node:
        raise ValueError("invalid node name %s", node)
    try:
        log.info("getting client config from %s", "config/" + node)
        with open("config/" + node) as fh:
            node_conf = json.load(fh)
    except Exception as e:
        log.warning("got %s opening %s", e, "config/" + node)
        abort(401, "unknown client")
    last = node_conf["last"]
    for key in node_conf["keys"]:
        msg = (node + " " + str(timestamp)).encode("UTF-8")
        hmac2 = hmac.new(key.encode("UTF-8"), msg, "SHA256")
        digest2 = hmac2.hexdigest()
        if hmac.compare_digest(digest1, digest2):
            if timestamp > node_conf["last"]:
                node_conf["last"] = timestamp
                os.replace("config/" + node, "config/" + node + ".old")
                with open("config/" + node, "w") as fh:
                    json.dump(node_conf, fh) # XXX
                return node
            else:
                abort(409, "timestamp out of sync")
    abort(401, "auth failed")

@app.get("/v")
def visualize():
    timeseries_ids = request.args.getlist("ts")
    timeseries_data = []
    for id in timeseries_ids:
        ts = LTS(id=id)
        timeseries_data.append(ts)
    return render_template("visualize.html", ts=timeseries_data)