ppt_chunker.py

from io import StringIO
from typing import List

from unstructured.partition.pptx import partition_pptx

from ordered_multimap import OrderedMultiIndexMapWeakRef

WRONG_NOUNS = {"BY", "IN", "ON", "INTO", "A", "AT", "WITH", "FROM", "TO", "AND", "OR", "BUT", "OWN", 'BEHIND', 'THROUGH', 'FIERCE', "'S", '&'}
NON_ENDING_PUNCT = {',', ':', ';', "'", '/', '-'}

def process_chunk(chunk, nlp):
    marked = []
        
    for i in range(len(chunk[1])):
        current = chunk[1][i]
            
        if (type(current) is list) and current[1].isupper() and (current[0] == ('Title' or 'UncategorizedText')):
            tokens = nlp(current[1])
            
            try:
                next_ = chunk[1][i+1]
                    
                if type(next_) is not list:
                    continue
                
            except IndexError:
                continue
                    
            if next_[1].isupper() and (next_[0] == ('Title' or 'UncategorizedText')):
                if (tokens[-1].pos_ in {'SYM', "ADP", 'ADV', 'PART', 'PRON', 'DET', "AUX", 'SCONJ', 'CONJ', "CCONJ"}) or ((tokens[-1].pos_ in {'PROPN', 'NOUN', 'VERB'}) and (str(tokens[-1]) in WRONG_NOUNS)):
                    chunk[1][i+1][1] = current[1] + ' ' + next_[1]
                    marked.append(i)

    for i in marked:
        del chunk[1][i]
            
    return chunk

def ppt_chunk(file_like, nlp):
    import time

    s = time.time()
    elements = partition_pptx(file=file_like)

    e = time.time()
    f = e - s
    print(f'TIME {f}')

    chunks = []
    current_chunk = []
    list_items = set()
    marked = set()

    for i, elem in enumerate(elements):
        if elem.category == "PageBreak":
            if current_chunk or list_items:
                if current_chunk:
                    current_chunk = [elem for elem in current_chunk if elem[1] not in marked]
                    
                if list_items:
                    duplicate = marked.intersection(list_items)
                    if duplicate:
                        list_items = list_items - duplicate

                    current_chunk.append("\n".join(list_items))
                    list_items = set()

                chunks.append([elem.id, current_chunk])
                current_chunk = []
        else:
            if (elem.text[-1] in NON_ENDING_PUNCT) and (elem.category != 'Table'):
                try:
                    next_ = elements[i+1]
                except IndexError:
                    pass
                elements[i+1].text = elem.text + ' ' + next_.text
                marked.add(elem.text)
                
            if (elem.category == "ListItem") or (elem.category == 'NarrativeText'):
                list_items.add(elem.text)
            else:
                current_chunk.append([elem.category, elem.text])

    sr = time.time()

    for chunk in chunks:
        chunk = process_chunk(chunk, nlp)

    tables = []
    j = 0
    
    while j < len(chunks):       
        new_sub_chunks = []
        only_tables = True
        title = ''
        
        for i, sub_chunk in enumerate(chunks[j][1]):
            print(f'TEST : {sub_chunk}')
            if (i == 0) and ((sub_chunk[0] == 'Title') or (sub_chunk[0] == 'UncategorizedText')):
                title = sub_chunk[1]
                
            if sub_chunk[0] == 'Table':
                if title != '':
                    tables.append([chunks[j][0], title, sub_chunk])
                else:
                    tables.append([chunks[j][0], sub_chunk])
            else:
                new_sub_chunks.append(sub_chunk)
                only_tables = False
        
        if only_tables:
            del chunks[j]
        else:
            chunks[j] = [chunks[j][0], new_sub_chunks]
            j += 1
        
    er = time.time()
    fr = er - s
    print(f'TIME INTERMEDIATE {fr}')
        
    weakDict = OrderedMultiIndexMapWeakRef()
    metadata_main_title = ''

    for chunk in chunks:
        nb_titles = 0
        nb_sub_titles = 0
        metadata_sub_title = ''
        
        for i, sub_chunk in enumerate(chunk[1]):
            if type(sub_chunk) is list:
                if sub_chunk[0] == 'Title':
                    if (i == 0) and (metadata_main_title != sub_chunk[1]):
                        metadata_main_title = sub_chunk[1]
                    nb_titles += 1
                elif sub_chunk[0] == 'UncategorizedText':
                    if ((i == 1) or (i == 0)) and (metadata_sub_title != sub_chunk[1]):
                        metadata_sub_title = sub_chunk[1]
                    nb_sub_titles += 1
            else:
                if (nb_titles <= 1) and (nb_sub_titles <= 1):
                    weakDict.insert(chunk[0], sub_chunk, metadata_main_title, metadata_sub_title)
                    break
                
            if i == len(chunk) - 1:
                weakDict.insert(chunk[0], "\n".join([c[1] for c in chunk[1]]), metadata_main_title, metadata_sub_title)

    for w in weakDict.all_texts():
        print(f'AFTER : {w}')
                    
    et = time.time()
    ft = et - s
    print(f'TIME FINAL {ft}')
        
    return weakDict, tables

    raise NotImplementedError(
        "file type not supported yet(pptx)")