57 lines
2 KiB
Python
57 lines
2 KiB
Python
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class PageLinksGenerator:
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# TODO inherit django paginator
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"""
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Calculate the pages for multiple links pagination.
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length -- the number of page links in pagination
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"""
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def __init__(self, length, current_page, total_pages):
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current_page = int(current_page)
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self.current_page = current_page
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self.start_page = None
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self.end_page = None
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self.page_range = None
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self.has_prev = None
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self.has_next = None
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start_page = current_page - length // 2
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end_page = current_page + length // 2
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# decision is based on the start page and the end page
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# both sides overflow
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if (start_page < 1 and end_page > total_pages)\
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or length >= total_pages:
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self.start_page = 1
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self.end_page = total_pages
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self.has_prev = False
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self.has_next = False
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elif start_page < 1 and not end_page > total_pages:
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self.start_page = 1
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# this won't overflow because the total pages are more than the length
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self.end_page = end_page - (start_page - 1)
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self.has_prev = False
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if end_page == total_pages:
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self.has_next = False
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else:
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self.has_next = True
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elif not start_page < 1 and end_page > total_pages:
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self.end_page = total_pages
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self.start_page = start_page - (end_page - total_pages)
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self.has_next = False
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if start_page == 1:
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self.has_prev = False
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else:
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self.has_prev = True
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# both sides do not overflow
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elif not start_page < 1 and not end_page > total_pages:
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self.start_page = start_page
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self.end_page = end_page
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self.has_prev = True
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self.has_next = True
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self.first_page = 1
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self.last_page = total_pages
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self.page_range = range(self.start_page, self.end_page + 1)
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# assert self.has_prev is not None and self.has_next is not None
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