import os
import io
import sys
import sqlite3
import argparse
import requests
from pydantic import BaseModel, validator
from typing import List, Dict, Tuple, Optional, Any, Sequence
from fatcat_openapi_client import ReleaseEntity, FileEntity
import internetarchive

from fatcat_scholar.api_entities import *
from fatcat_scholar.djvu import djvu_extract_leaf_texts
from fatcat_scholar.sandcrawler import SandcrawlerPostgrestClient, SandcrawlerMinioClient
from fatcat_scholar.issue_db import IssueDB, SimIssueRow
from fatcat_scholar.schema import es_biblio_from_release, es_release_from_release, DocType, IntermediateBundle


def truncate_pub_meta(full: Dict[str, Any]) -> Dict[str, Any]:
    """
    Takes a complete archive.org metadata dictionary for a publication
    collection, and simplifies it by removing fields. Motivation is to make
    intermediate bundle files smaller.
    """
    full.pop('files')
    if 'ulrichs' in full and full['ulrichs']:
        full['ulrichs'][0].pop('reviews_mfl')
        full['ulrichs'][0].pop('editorial_description')

        # these are interesting, but just too long
        full['ulrichs'][0].pop('online_availability_full_text')
        full['ulrichs'][0].pop('abstracting_indexing')
        full['ulrichs'][0].pop('publisher_and_ordering_details')
    return full

def truncate_issue_meta(full: Dict[str, Any]) -> Dict[str, Any]:
    """
    Same as truncate_pub_meta() but for issue item metadata
    """
    full.pop('files')
    return full

class SimPipeline():

    def __init__(self, issue_db: IssueDB):
        self.issue_db: IssueDB = issue_db
        self.ia_client = internetarchive.get_session()

    def fetch_sim_issue(self, issue_db_row: Any) -> Optional[Any]:
        """
        issue_item 
        pages: str
        page_texts: list
            raw_text
            page_num
            leaf_num
        release_ident: Optional[str]
        pub_item_metadata
        issue_item_metadata
        """
        # fetch full metadata from API
        issue_meta = self.ia_client.get_metadata(issue_db_row['issue_item'])
        pub_meta = self.ia_client.get_metadata(issue_db_row['pub_collection'])

        leaf_index = dict()
        leaf_list = []
        if not 'page_numbers' in issue_meta:
            # TODO: warn
            return None
        for entry in issue_meta['page_numbers'].get('pages', []):
            page_num = entry['pageNumber']
            leaf_index[entry['leafNum']] = page_num
            if not (page_num and page_num.isdigit()):
                continue
            page_num = int(page_num)
            leaf_list.append(entry['leafNum'])

        if not leaf_list:
            return None

        page_texts: List[Dict[str, Any]] = []
        issue_item = self.ia_client.get_item(issue_db_row['issue_item'])
        issue_item_djvu = issue_item.get_file(issue_db_row['issue_item'] + "_djvu.xml")

        # override 'close()' method so we can still read out contents
        djvu_bytes = io.BytesIO()
        djvu_bytes.close = lambda: None     # type: ignore
        assert issue_item_djvu.download(fileobj=djvu_bytes) == True
        djvu_bytes.seek(0)
        djvu_xml = io.StringIO(djvu_bytes.read().decode("UTF-8"))
        del(djvu_bytes)

        leaf_dict = djvu_extract_leaf_texts(djvu_xml)

        for leaf_num, raw_text in leaf_dict.items():
            page_texts.append(dict(page_num=leaf_index.get(leaf_num), leaf_num=leaf_num, raw_text=raw_text))

        return dict(
            issue_item=issue_db_row['issue_item'],
            pages=None,
            page_texts=page_texts,
            release_ident=None,
            pub_item_metadata=truncate_pub_meta(pub_meta),
            issue_item_metadata=truncate_issue_meta(issue_meta),
        )

    def run_issue_db(self, limit: int = None):
        count = 0
        self.issue_db.db.row_factory = sqlite3.Row
        cur = self.issue_db.db.cursor()
        for row in cur.execute('SELECT * FROM sim_issue LEFT JOIN sim_pub ON sim_issue.sim_pubid = sim_pub.sim_pubid WHERE sim_issue.release_count < 3'):
            # filter out "contents" and "index" items
            # TODO: more filters; also redundant with IssueDB code?
            if row['issue_item'].endswith('_contents') or row['issue_item'].endswith('_index'):
                continue
            try:
                full_issue = self.fetch_sim_issue(row)
            except requests.exceptions.ReadTimeout as e:
                print(str(e), file=sys.stderr)
                continue
            if not full_issue:
                continue
            for leaf in full_issue['page_texts']:
                bundle = IntermediateBundle(
                    doc_type=DocType.sim_page,
                    releases=[],
                    biblio_release_ident=None,
                    grobid_fulltext=None,
                    pdftotext_fulltext=None,
                    sim_fulltext=dict(
                        issue_item=full_issue['issue_item'],
                        pages=str(leaf['page_num']),
                        page_texts=[leaf],
                        release_ident=None,
                        pub_item_metadata=full_issue['pub_item_metadata'],
                        issue_item_metadata=full_issue['issue_item_metadata'],
                    )
                )
                print(bundle.json())
                count += 1
                if limit is not None and count >= limit:
                    break
            if limit is not None and count >= limit:
                break

def main():
    """
    Run this command like:

        python -m fatcat_scholar.sim_pipeline
    """

    parser = argparse.ArgumentParser(
        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
    subparsers = parser.add_subparsers()

    parser.add_argument("--issue-db-file",
        help="sqlite3 database file to open",
        default='data/issue_db.sqlite',
        type=str)

    sub = subparsers.add_parser('run_issue_db',
        help="iterates through entire IssueDB")
    sub.set_defaults(func='run_issue_db')
    sub.add_argument("--limit",
        help="maximum number of pages to index",
        type=int)

    args = parser.parse_args()
    if not args.__dict__.get("func"):
        print("tell me what to do! (try --help)")
        sys.exit(-1)

    sp = SimPipeline(issue_db=IssueDB(args.issue_db_file))

    if args.func == 'run_issue_db':
        sp.run_issue_db(limit=args.limit)
    else:
        func = getattr(sp, args.func)
        func()

if __name__=="__main__":
    main()