views.py

import math
import re
from urllib.parse import urlencode

from django.conf import settings
from django.http import JsonResponse

import requests

from core.views import TranslatedTemplateView

from .forms import SearchForm


# Search.gov API docs: https://open.gsa.gov/api/searchgov-results/
API_ENDPOINT = "https://api.gsa.gov/technology/searchgov/v2/results/i14y?{}"
RESULTS_PER_PAGE = 20


def get_affiliate(context):
    """Given a request, return the appropriate affiliate for Search.gov.
    Our default affiliate code is "cfpb". We have a separate Spanish-language
    index named "cfpb_es".
    """
    if context.get("current_language") == "es":
        return "cfpb_es"

    return "cfpb"


def get_api_key(context):
    if context.get("current_language") == "es":
        return settings.SEARCHGOV_ES_API_KEY
    return settings.SEARCHGOV_API_KEY


def encode_url(params):
    return API_ENDPOINT.format(urlencode(params))


def strip_title_suffix(title):
    """Remove the ' | Consumer Financial Protection Bureau' from the end
    of search result titles. Becuase one or more words may be enclosed by
    \ue000 and \ue001 characters if they match a search term, we have to be
    a little flexible with the regex.
    """
    suffix_regex = r" \| .*"
    cleaned_title = re.sub(suffix_regex, "", title)
    return cleaned_title


class SearchView(TranslatedTemplateView):
    template_name = "searchgov/index.html"

    def get(self, request, **kwargs):
        context = self.get_context_data(**kwargs)
        form = SearchForm(request.GET)
        results = []
        recommended = []
        total_pages = 1
        current_page = 1
        count = 0
        offset = 0
        start_index = 1
        end_index = RESULTS_PER_PAGE
        query = ""
        affiliate = get_affiliate(context)
        api_key = get_api_key(context)

        if form.is_valid():
            query = form.cleaned_data["q"]
            offset = (form.cleaned_data["page"] - 1) * RESULTS_PER_PAGE
            response = requests.get(
                encode_url(
                    {
                        "affiliate": affiliate,
                        "access_key": api_key,
                        "limit": RESULTS_PER_PAGE,
                        "offset": offset,
                        "query": query,
                    }
                )
            )

            if response.status_code == 200:
                json_data = response.json()
                data = json_data["web"]
                results = data["results"]
                recommended = json_data["text_best_bets"]
                count = data["total"]

                if count > 999:
                    count = 999

                # Protect against page shenanigans
                if offset < count:
                    total_pages = math.ceil(count / RESULTS_PER_PAGE)
                    current_page = form.cleaned_data["page"]

                    start_index = offset + 1
                    end_index = offset + RESULTS_PER_PAGE

                    if end_index > count:
                        end_index = count

                    # Post proprocess results
                    for res in results:
                        # Strip " | CFPB" suffix
                        res["title"] = strip_title_suffix(res["title"])

                else:
                    count = 0

        context_data = {
            "query": query,
            "count": count,
            "start_index": start_index,
            "end_index": end_index,
            "total_pages": total_pages,
            "current_page": current_page,
            "recommended": recommended,
            "results": results,
            "pagination_params": {"q": query} if query else {},
        }

        if form.cleaned_data.get("format") == "json":
            return JsonResponse(context_data)

        context.update(context_data)

        return self.render_to_response(context)