# encoding: utf-8
from __future__ import print_function
from __future__ import absolute_import
import datetime
import time
import re
import logging
import click
import ckan.model as model

from . import dbutil, utils

log = logging.getLogger(__name__)
PACKAGE_URL = "/dataset/"  # XXX get from routes...

RESOURCE_URL_REGEX = re.compile("/dataset/[a-z0-9-_]+/resource/([a-z0-9-_]+)")
DATASET_EDIT_REGEX = re.compile("/dataset/edit/([a-z0-9-_]+)")


def get_commands():
    return [googleanalytics]


@click.group(short_help=u"GoogleAnalytics commands")
def googleanalytics():
    pass


@googleanalytics.command()
def init():
    """Initialise the local stats database tables"""
    model.Session.remove()
    model.Session.configure(bind=model.meta.engine)
    dbutil.init_tables()
    log.info("Set up statistics tables in main database")


@googleanalytics.command(short_help=u"Load data from Google Analytics API")
@click.argument("credentials", type=click.Path(exists=True))
@click.option("-s", "--start-date", required=False)
def load(credentials, start_date):
    """Parse data from Google Analytics API and store it
    in a local database
    """
    from .ga_auth import init_service, get_profile_id

    try:
        service = init_service(credentials)
    except TypeError as e:
        raise Exception("Unable to create a service: {0}".format(e))
    profile_id = get_profile_id(service)

    if start_date:
        bulk_import(service, profile_id, start_date)
    else:
        query = "ga:pagePath=~%s,ga:pagePath=~%s" % (
            PACKAGE_URL,
            utils.config_prefix(),
        )
        packages_data = get_ga_data(service, profile_id, query_filter=query)
        save_ga_data(packages_data)
        log.info("Saved %s records from google" % len(packages_data))


###############################################################################
#                                     xxx                                     #
###############################################################################


def internal_save(packages_data, summary_date):
    engine = model.meta.engine
    # clear out existing data before adding new
    sql = (
        """DELETE FROM tracking_summary
             WHERE tracking_date='%s'; """
        % summary_date
    )
    engine.execute(sql)

    for url, count in list(packages_data.items()):
        # If it matches the resource then we should mark it as a resource.
        # For resources we don't currently find the package ID.
        if RESOURCE_URL_REGEX.match(url):
            tracking_type = "resource"
        else:
            tracking_type = "page"

        sql = """INSERT INTO tracking_summary
                 (url, count, tracking_date, tracking_type)
                 VALUES (%s, %s, %s, %s);"""
        engine.execute(sql, url, count, summary_date, tracking_type)

    # get ids for dataset urls
    sql = """UPDATE tracking_summary t
             SET package_id = COALESCE(
                 (SELECT id FROM package p WHERE t.url =  %s || p.name)
                 ,'~~not~found~~')
             WHERE t.package_id IS NULL AND tracking_type = 'page';"""
    engine.execute(sql, PACKAGE_URL)

    # get ids for dataset edit urls which aren't captured otherwise
    sql = """UPDATE tracking_summary t
             SET package_id = COALESCE(
                 (SELECT id FROM package p WHERE t.url =  %s || p.name)
                 ,'~~not~found~~')
             WHERE t.package_id = '~~not~found~~'
             AND tracking_type = 'page';"""
    engine.execute(sql, "%sedit/" % PACKAGE_URL)

    # update summary totals for resources
    sql = """UPDATE tracking_summary t1
             SET running_total = (
                SELECT sum(count)
                FROM tracking_summary t2
                WHERE t1.url = t2.url
                AND t2.tracking_date <= t1.tracking_date
             ) + t1.count
             ,recent_views = (
                SELECT sum(count)
                FROM tracking_summary t2
                WHERE t1.url = t2.url
                AND t2.tracking_date <= t1.tracking_date
                AND t2.tracking_date >= t1.tracking_date - %s
             ) + t1.count
             WHERE t1.running_total = 0 AND tracking_type = 'resource';"""
    engine.execute(sql, utils.config_recent_view_days())

    # update summary totals for pages
    sql = """UPDATE tracking_summary t1
             SET running_total = (
                SELECT sum(count)
                FROM tracking_summary t2
                WHERE t1.package_id = t2.package_id
                AND t2.tracking_date <= t1.tracking_date
             ) + t1.count
             ,recent_views = (
                SELECT sum(count)
                FROM tracking_summary t2
                WHERE t1.package_id = t2.package_id
                AND t2.tracking_date <= t1.tracking_date
                AND t2.tracking_date >= t1.tracking_date - %s
             ) + t1.count
             WHERE t1.running_total = 0 AND tracking_type = 'page'
             AND t1.package_id IS NOT NULL
             AND t1.package_id != '~~not~found~~';"""
    engine.execute(sql, utils.config_recent_view_days())


def bulk_import(service, profile_id, start_date=None):
    if start_date:
        # Get summeries from specified date
        start_date = datetime.datetime.strptime(start_date, "%Y-%m-%d")
    else:
        # No date given. See when we last have data for and get data
        # from 2 days before then in case new data is available.
        # If no date here then use 2010-01-01 as the start date
        engine = model.meta.engine
        sql = """SELECT tracking_date from tracking_summary
                 ORDER BY tracking_date DESC LIMIT 1;"""
        result = engine.execute(sql).fetchall()
        if result:
            start_date = result[0]["tracking_date"]
            start_date += datetime.timedelta(-2)
            # convert date to datetime
            combine = datetime.datetime.combine
            start_date = combine(start_date, datetime.time(0))
        else:
            start_date = datetime.datetime(2011, 1, 1)
    end_date = datetime.datetime.now()
    while start_date < end_date:
        stop_date = start_date + datetime.timedelta(1)
        packages_data = get_ga_data_new(
            service, profile_id, start_date=start_date, end_date=stop_date
        )
        internal_save(packages_data, start_date)
        # sleep to rate limit requests
        time.sleep(0.25)
        start_date = stop_date
        log.info("%s received %s" % (len(packages_data), start_date))
        print("%s received %s" % (len(packages_data), start_date))


def get_ga_data_new(service, profile_id, start_date=None, end_date=None):
    """Get raw data from Google Analtyics for packages and
    resources.

    Returns a dictionary like::

       {'identifier': 3}
    """
    start_date = start_date.strftime("%Y-%m-%d")
    end_date = end_date.strftime("%Y-%m-%d")

    packages = {}
    query = "ga:pagePath=~%s,ga:pagePath=~%s" % (
        PACKAGE_URL,
        utils.config_prefix(),
    )
    metrics = "ga:uniquePageviews"
    sort = "-ga:uniquePageviews"

    start_index = 1
    max_results = 10000
    # data retrival is chunked
    completed = False
    while not completed:
        results = (
            service.data()
            .ga()
            .get(
                ids="ga:%s" % profile_id,
                filters=query,
                dimensions="ga:pagePath",
                start_date=start_date,
                start_index=start_index,
                max_results=max_results,
                metrics=metrics,
                sort=sort,
                end_date=end_date,
            )
            .execute()
        )
        result_count = len(results.get("rows", []))
        if result_count < max_results:
            completed = True

        for result in results.get("rows", []):
            package = result[0]
            package = "/" + "/".join(package.split("/")[2:])
            count = result[1]
            packages[package] = int(count)

        start_index += max_results

        # rate limiting
        time.sleep(0.2)
    return packages


def save_ga_data(packages_data):
    """Save tuples of packages_data to the database"""
    for identifier, visits in list(packages_data.items()):
        recently = visits.get("recent", 0)
        ever = visits.get("ever", 0)
        matches = RESOURCE_URL_REGEX.match(identifier)
        if matches:
            resource_url = identifier[len(utils.config_prefix()):]
            resource = (
                model.Session.query(model.Resource)
                .autoflush(True)
                .filter_by(id=matches.group(1))
                .first()
            )
            if not resource:
                log.warning("Couldn't find resource %s" % resource_url)
                continue
            dbutil.update_resource_visits(resource.id, recently, ever)
            log.info("Updated %s with %s visits" % (resource.id, visits))
        else:
            package_name = identifier[len(PACKAGE_URL):]
            if "/" in package_name:
                log.warning("%s not a valid package name" % package_name)
                continue
            item = model.Package.by_name(package_name)
            if not item:
                log.warning("Couldn't find package %s" % package_name)
                continue
            dbutil.update_package_visits(item.id, recently, ever)
            log.info("Updated %s with %s visits" % (item.id, visits))
    model.Session.commit()


def ga_query(
    service,
    profile_id,
    query_filter=None,
    from_date=None,
    metrics=None,
):
    """Execute a query against Google Analytics"""
    now = datetime.datetime.now()
    to_date = now.strftime("%Y-%m-%d")
    if isinstance(from_date, datetime.date):
        from_date = from_date.strftime("%Y-%m-%d")
    if not metrics:
        metrics = "ga:visits,ga:visitors,ga:newVisits,ga:uniquePageviews"
    sort = "-ga:uniquePageviews"

    print("%s -> %s" % (from_date, to_date))

    results = (
        service.data()
        .ga()
        .get(
            ids="ga:" + profile_id,
            start_date=from_date,
            end_date=to_date,
            dimensions="ga:pagePath",
            metrics=metrics,
            sort=sort,
            start_index=1,
            filters=query_filter,
            max_results=10000,
        )
        .execute()
    )
    return results


def get_ga_data(service, profile_id, query_filter):
    """Get raw data from Google Analtyics for packages and
    resources, and for both the last two weeks and ever.

    Returns a dictionary like::

       {'identifier': {'recent':3, 'ever':6}}
    """
    now = datetime.datetime.now()
    recent_date = now - datetime.timedelta(utils.config_recent_view_days())
    recent_date = recent_date.strftime("%Y-%m-%d")
    floor_date = datetime.date(2005, 1, 1)
    packages = {}
    queries = ["ga:pagePath=~%s" % PACKAGE_URL]
    dates = {"recent": recent_date, "ever": floor_date}
    for date_name, date in list(dates.items()):
        for query in queries:
            results = ga_query(
                service,
                profile_id,
                query_filter=query,
                metrics="ga:uniquePageviews",
                from_date=date,
            )
            if "rows" in results:
                for result in results.get("rows"):
                    package = result[0]
                    if not package.startswith(PACKAGE_URL):
                        package = "/" + "/".join(package.split("/")[2:])

                    count = result[1]
                    # Make sure we add the different representations of the
                    # same dataset /mysite.com & /www.mysite.com ...
                    val = 0
                    if package in packages and date_name in packages[package]:
                        val += packages[package][date_name]
                    packages.setdefault(package, {})[date_name] = (
                        int(count) + val
                    )
    return packages