from io import BytesIO
from time import sleep

import pdfplumber

from data.sig_ref import SIGRef
from providers.sigrefdata.file_download_sig_ref_data_provider import FileDownloadSIGRefDataProvider


class FEA(FileDownloadSIGRefDataProvider):
    """SIG ref data provider for Diploma Faros de España"""

    POLL_INTERVAL_DAYS = 30
    SIG = "FEA"
    DATA_URL = "http://ea5ol.net/Lista%20Faros.pdf"

    def __init__(self, provider_config):
        super().__init__(self.SIG, provider_config, self.DATA_URL, self.POLL_INTERVAL_DAYS)

    def _http_response_to_data(self, http_response):
        new_data = []

        # Use PDFPlumber to extract the tables in the PDF
        with pdfplumber.open(BytesIO(http_response.content)) as pdf:
            all_rows = []

            for page_number, page in enumerate(pdf.pages, start=1):
                tables = page.extract_tables()

                for table_number, table in enumerate(tables, start=1):
                    if not table:
                        continue

                    rows = [row for row in table if any(cell and cell.strip() for cell in row)]
                    all_rows.extend(rows)

        for row in all_rows:
            if not "REF" in row[0] and not "\n" in row[0]:
                # FEA references are technically [DE]\-\d{4}(\.\d)? but spotters always seem to miss out the D- or E-
                # prefix and just use FEA 1234, so we treat FEA reference IDs as if they were just the number.
                ref_id = row[0].strip().replace("D-", "").replace("E-", "")
                new_data.append(SIGRef(sig=self.SIG, id=ref_id, name=row[1].strip(), ref_type="Lighthouse"))

            # Bail out if a stop has been requested, i.e. the program is shutting down - no need to parse the rest of
            # the data in this case
            if self._stop_event.is_set():
                break

            # Very short pause. This will extend the time to handle sig refs by a few seconds but will ensure some time
            # is available for other threads e.g. the web server.
            sleep(0.001)

        return new_data