/b-gtk/fix-viz

# -*- coding: UTF-8 -*-

"""Directed graph production.

This module contains the code to produce an ordered directed graph of a

bzr branch, such as we display in the tree view at the top of the bzrk

window.

"""

__copyright__ = "Copyright © 2005 Canonical Ltd."

__author__    = "Scott James Remnant <scott@ubuntu.com>"

from bzrlib.tsort import merge_sort

def linegraph(branch, start, maxnum):

    """Produce a directed graph of a bzr branch.

    Returns a list of tuples of (revid,

                                 node,

                                 lines,

                                 parents,

                                 children,

                                 revno_sequence).

    Node is a tuple of (column, colour) with column being a zero-indexed

    column number of the graph that this revision represents and colour

    being a zero-indexed colour (which doesn't specify any actual colour

    in particular) to draw the node in.

    Lines is a list of tuples which represent lines you should draw away

    from the revision, if you also need to draw lines into the revision

    you should use the lines list from the previous iteration.  Each

    typle in the list is in the form (start, end, colour) with start and

    end being zero-indexed column numbers and colour as in node.

    It's up to you how to actually draw the nodes and lines (straight,

    curved, kinked, etc.) and to pick the actual colours for each index.

    """

    mainline = branch.revision_history()

    graph_parents = branch.repository.get_revision_graph(start)

    graph_children = {}

    for revid in graph_parents.iterkeys():

        graph_children[revid] = []

    merge_sorted_revisions = merge_sort(

        graph_parents,

        start,

        mainline,

        generate_revno=True)

    revid_index = {}

    branch_lines = {}

    linegraph = []    

    for (rev_index, (sequence_number,

                     revid,

                     merge_depth,

                     revno_sequence,

                     end_of_merge)) in enumerate(merge_sorted_revisions):

        revid_index[revid] = rev_index

        branch_id = revno_sequence[0:-1]

        branch_line = None

        if branch_id not in branch_lines:

            branch_line = {"branch_id": branch_id,

                           "rev_indexes": [],

                           "min_index": rev_index,

                           "max_index": 0}

            branch_lines[branch_id] = branch_line

        else:

            branch_line = branch_lines[branch_id]

        branch_line["rev_indexes"].append(rev_index)

        if rev_index > branch_line["max_index"]:

            branch_line["max_index"] = rev_index

        parents = graph_parents[revid]

        for parent_revid in parents:

            graph_children[parent_revid].append(revid)

        linegraph.append([revid,

                          None,

                          [],

                          parents,

                          None,

                          revno_sequence])

    branch_ids = branch_lines.keys()

    def branch_id_cmp(x, y):

        len_x = len(x)

        len_y = len(y)

        if len_x == len_y:

            return -cmp(x, y)

        return cmp(len_x, len_y)

    branch_ids.sort(branch_id_cmp)

    lines = []

    empty_column = [False for i in range(len(graph_parents))]

    columns = [list(empty_column)]

    for branch_id in branch_ids:

        branch_line = branch_lines[branch_id]

        parent_col_index = 0

        if len(branch_id) > 1:

            parent_branch_id = branch_id[0:-2]

            parent_col_index = branch_lines[parent_branch_id]["col_index"]

        branch_line["col_index"] = append_line(columns,

                                               (branch_line["min_index"],

                                                branch_line["max_index"]),

                                               empty_column,

                                               parent_col_index)

        color = reduce(lambda x, y: x+y, branch_id, 0)

        col_index = branch_line["col_index"]

        node = (col_index, color)        

        for rev_index in branch_line["rev_indexes"]:

            (sequence_number,

                 revid,

                 merge_depth,

                 revno_sequence,

                 end_of_merge) = merge_sorted_revisions[rev_index]

            linegraph[rev_index][1] = node

            linegraph[rev_index][4] = graph_children[revid]

            for parent_revid in graph_parents[revid]:

                if parent_revid in revid_index:

                    parent_index = revid_index[parent_revid]

                    parent_revno = merge_sorted_revisions[parent_index][3]

                    parent_branch_id = parent_revno[0:-1]

                    col_index = None

                    if branch_id != parent_branch_id and \

                                    parent_index - rev_index > 1:

                        col_index = append_line(columns,

                                                (rev_index+1, parent_index-1),

                                                empty_column,

                                                branch_line["col_index"])

                    lines.append((rev_index, parent_index, col_index))

    for (child_index, parent_index, line_col_index) in lines:

        child_col_index = linegraph[child_index][1][0]

        parent_node = linegraph[parent_index][1]

        parent_col_index = parent_node[0]

        color = parent_node[1]

        if line_col_index:

            linegraph[child_index][2].append(

                (child_col_index,

                 line_col_index,

                 color))

            for line_part_index in range(child_index+1, parent_index-1):

                linegraph[line_part_index][2].append(

                    (line_col_index,   

                     line_col_index,

                     color))

            linegraph[parent_index-1][2].append(

                (line_col_index,

                 parent_col_index,

                 color))

        else:

            linegraph[child_index][2].append(

                (child_col_index,

                 parent_col_index,

                 color))

            for line_part_index in range(child_index+1, parent_index):

                linegraph[line_part_index][2].append(

                    (parent_col_index,   

                     parent_col_index,

                     color))

    return (linegraph, revid_index)

def append_line(columns, line, empty_column, starting_col_index):

    line_range = range(line[0], line[1]+1)

    col_order = range(starting_col_index, -1, -1) + \

                range(starting_col_index+1, len(columns))

    for col_index in col_order:

        column = columns[col_index]

        has_overlaping_line = False

        for row_index in line_range:

            if column[row_index]:

                has_overlaping_line = True

                break

        if not has_overlaping_line:

            break

    else:

        col_index = len(columns)

        column = list(empty_column)

        columns.append(column)

    for row_index in line_range:

        column[row_index] = True

    return col_index

def same_branch(a, b):

    """Return whether we think revisions a and b are on the same branch."""

    if len(a.parent_ids) == 1:

        # Defacto same branch if only parent

        return True

    elif a.committer == b.committer:

        # Same committer so may as well be

        return True

    else:

        return False