# coding: utf8
from __future__ import unicode_literals, division, print_function

import plac
from timeit import default_timer as timer
import random
import numpy.random

from ..gold import GoldCorpus
from ..util import prints
from .. import util
from .. import displacy


random.seed(0)
numpy.random.seed(0)


@plac.annotations(
    model=("model name or path", "positional", None, str),
    data_path=("location of JSON-formatted evaluation data", "positional",
               None, str),
    gold_preproc=("use gold preprocessing", "flag", "G", bool),
    gpu_id=("use GPU", "option", "g", int),
    displacy_path=("directory to output rendered parses as HTML", "option",
                   "dp", str),
    displacy_limit=("limit of parses to render as HTML", "option", "dl", int))
def evaluate(model, data_path, gpu_id=-1, gold_preproc=False, displacy_path=None,
             displacy_limit=25):
    """
    Evaluate a model. To render a sample of parses in a HTML file, set an
    output directory as the displacy_path argument.
    """
    if gpu_id >= 0:
        util.use_gpu(gpu_id)
    util.set_env_log(False)
    data_path = util.ensure_path(data_path)
    displacy_path = util.ensure_path(displacy_path)
    if not data_path.exists():
        prints(data_path, title="Evaluation data not found", exits=1)
    if displacy_path and not displacy_path.exists():
        prints(displacy_path, title="Visualization output directory not found",
               exits=1)
    corpus = GoldCorpus(data_path, data_path)
    nlp = util.load_model(model)
    dev_docs = list(corpus.dev_docs(nlp, gold_preproc=gold_preproc))
    begin = timer()
    scorer = nlp.evaluate(dev_docs, verbose=False)
    end = timer()
    nwords = sum(len(doc_gold[0]) for doc_gold in dev_docs)
    print_results(scorer, time=end - begin, words=nwords,
                  wps=nwords / (end - begin))
    if displacy_path:
        docs, golds = zip(*dev_docs)
        render_deps = 'parser' in nlp.meta.get('pipeline', [])
        render_ents = 'ner' in nlp.meta.get('pipeline', [])
        render_parses(docs, displacy_path, model_name=model,
                      limit=displacy_limit, deps=render_deps, ents=render_ents)
        msg = "Generated %s parses as HTML" % displacy_limit
        prints(displacy_path, title=msg)


def render_parses(docs, output_path, model_name='', limit=250, deps=True,
                  ents=True):
    docs[0].user_data['title'] = model_name
    if ents:
        with (output_path / 'entities.html').open('w') as file_:
            html = displacy.render(docs[:limit], style='ent', page=True)
            file_.write(html)
    if deps:
        with (output_path / 'parses.html').open('w') as file_:
            html = displacy.render(docs[:limit], style='dep', page=True,
                                   options={'compact': True})
            file_.write(html)


def print_progress(itn, losses, dev_scores, wps=0.0):
    scores = {}
    for col in ['dep_loss', 'tag_loss', 'uas', 'tags_acc', 'token_acc',
                'ents_p', 'ents_r', 'ents_f', 'wps']:
        scores[col] = 0.0
    scores['dep_loss'] = losses.get('parser', 0.0)
    scores['ner_loss'] = losses.get('ner', 0.0)
    scores['tag_loss'] = losses.get('tagger', 0.0)
    scores.update(dev_scores)
    scores['wps'] = wps
    tpl = '\t'.join((
        '{:d}',
        '{dep_loss:.3f}',
        '{ner_loss:.3f}',
        '{uas:.3f}',
        '{ents_p:.3f}',
        '{ents_r:.3f}',
        '{ents_f:.3f}',
        '{tags_acc:.3f}',
        '{token_acc:.3f}',
        '{wps:.1f}'))
    print(tpl.format(itn, **scores))


def print_results(scorer, time, words, wps):
    results = {
        'Time': '%.2f s' % time,
        'Words': words,
        'Words/s': '%.0f' % wps,
        'TOK': '%.2f' % scorer.token_acc,
        'POS': '%.2f' % scorer.tags_acc,
        'UAS': '%.2f' % scorer.uas,
        'LAS': '%.2f' % scorer.las,
        'NER P': '%.2f' % scorer.ents_p,
        'NER R': '%.2f' % scorer.ents_r,
        'NER F': '%.2f' % scorer.ents_f}
    util.print_table(results, title="Results")