# sumaexcel/merge.py
from typing import List, Tuple, Dict
from openpyxl.worksheet.worksheet import Worksheet
from openpyxl.worksheet.merge import MergedCellRange

class MergeManager:
    """Handle merge cell operations""" 

    def __init__(self, worksheet: Worksheet):
        self.worksheet = worksheet
        self._merged_ranges: List[MergedCellRange] = []
        self._load_merged_ranges()

    def _load_merged_ranges(self) -> None:
        """Load existing merged ranges from worksheet""" 
        self._merged_ranges = list(self.worksheet.merged_cells.ranges)

    def merge_cells(
        self,
        start_row: int,
        start_col: int,
        end_row: int,
        end_col: int
    ) -> None:
        """Merge cells in specified range""" 
        self.worksheet.merge_cells(
            start_row=start_row,
            start_column=start_col,
            end_row=end_row,
            end_column=end_col
        )
        self._load_merged_ranges()

    def unmerge_cells(
        self,
        start_row: int,
        start_col: int,
        end_row: int,
        end_col: int
    ) -> None:
        """Unmerge cells in specified range""" 
        self.worksheet.unmerge_cells(
            start_row=start_row,
            start_column=start_col,
            end_row=end_row,
            end_column=end_col
        )
        self._load_merged_ranges()

    def copy_merged_cells(
        self,
        source_range: Tuple[int, int, int, int],
        target_start_row: int,
        target_start_col: int
    ) -> None:
        """Copy merged cells from source range to target position""" 
        src_row1, src_col1, src_row2, src_col2 = source_range
        row_offset = target_start_row - src_row1
        col_offset = target_start_col - src_col1

        for merged_range in self._merged_ranges:
            if (src_row1 <= merged_range.min_row <= src_row2 and
                src_col1 <= merged_range.min_col <= src_col2):
                new_row1 = merged_range.min_row + row_offset
                new_col1 = merged_range.min_col + col_offset
                new_row2 = merged_range.max_row + row_offset
                new_col2 = merged_range.max_col + col_offset

                self.merge_cells(new_row1, new_col1, new_row2, new_col2)

    def shift_merged_cells(
        self,
        start_row: int,
        rows: int = 0,
        cols: int = 0
    ) -> None:
        """Shift merged cells by specified number of rows and columns""" 
        new_ranges = []
        for merged_range in self._merged_ranges:
            if merged_range.min_row >= start_row:
                new_row1 = merged_range.min_row + rows
                new_col1 = merged_range.min_col + cols
                new_row2 = merged_range.max_row + rows
                new_col2 = merged_range.max_col + cols

                self.worksheet.unmerge_cells(
                    start_row=merged_range.min_row,
                    start_column=merged_range.min_col,
                    end_row=merged_range.max_row,
                    end_column=merged_range.max_col
                )

                new_ranges.append((new_row1, new_col1, new_row2, new_col2))

        for new_range in new_ranges:
            self.merge_cells(*new_range)