spaCy/spacy/displacy/render.py

# coding: utf8
from __future__ import unicode_literals

from .templates import TPL_DEP_SVG, TPL_DEP_WORDS, TPL_DEP_ARCS
from .templates import TPL_ENT, TPL_ENTS, TPL_FIGURE, TPL_TITLE, TPL_PAGE
from ..util import minify_html


class DependencyRenderer(object):
    """Render dependency parses as SVGs."""
    style = 'dep'

    def __init__(self, options={}):
        """Initialise dependency renderer.

        options (dict): Visualiser-specific options (compact, word_spacing,
                        arrow_spacing, arrow_width, arrow_stroke, distance,
                        offset_x, color, bg, font)
        """
        self.compact = options.get('compact', False)
        distance, arrow_width = (85, 8) if self.compact else (175, 10)
        self.word_spacing = options.get('word_spacing', 45)
        self.arrow_spacing = options.get('arrow_spacing', 20)
        self.arrow_width = options.get('arrow_width', arrow_width)
        self.arrow_stroke = options.get('arrow_stroke', 2)
        self.distance = options.get('distance', distance)
        self.offset_x = options.get('offset_x', 50)
        self.color = options.get('color', '#000000')
        self.bg = options.get('bg', '#ffffff')
        self.font = options.get('font', 'Arial')

    def render(self, parsed, page=False, minify=False):
        """Render complete markup.

        parsed (list): Dependency parses to render.
        page (bool): Render parses wrapped as full HTML page.
        minify (bool): Minify HTML markup.
        RETURNS (unicode): Rendered SVG or HTML markup.
        """
        rendered = [self.render_svg(i, p['words'], p['arcs'])
                    for i, p in enumerate(parsed)]
        if page:
            content = ''.join([TPL_FIGURE.format(content=svg) for svg in rendered])
            markup = TPL_PAGE.format(content=content)
        else:
            markup = ''.join(rendered)
        if minify:
            return minify_html(markup)
        return markup

    def render_svg(self, render_id, words, arcs):
        """Render SVG.

        render_id (int): Unique ID, typically index of document.
        words (list): Individual words and their tags.
        arcs (list): Individual arcs and their start, end, direction and label.
        RETURNS (unicode): Rendered SVG markup.
        """
        self.levels = self.get_levels(arcs)
        self.highest_level = len(self.levels)
        self.offset_y = self.distance/2*self.highest_level+self.arrow_stroke
        self.width = self.offset_x+len(words)*self.distance
        self.height = self.offset_y+3*self.word_spacing
        self.id = render_id
        words = [self.render_word(w['text'], w['tag'], i)
                 for i, w in enumerate(words)]
        arcs = [self.render_arrow(a['label'], a['start'], a['end'], a['dir'], i)
                for i, a in enumerate(arcs)]
        content = ''.join(words) + ''.join(arcs)
        return TPL_DEP_SVG.format(id=self.id, width=self.width, height=self.height,
                                  color=self.color, bg=self.bg, font=self.font,
                                  content=content)

    def render_word(self, text, tag, i):
        """Render individual word.

        text (unicode): Word text.
        tag (unicode): Part-of-speech tag.
        i (int): Unique ID, typically word index.
        RETURNS (unicode): Rendered SVG markup.
        """
        y = self.offset_y+self.word_spacing
        x = self.offset_x+i*self.distance
        return TPL_DEP_WORDS.format(text=text, tag=tag, x=x, y=y)

    def render_arrow(self, label, start, end, direction, i):
        """Render indivicual arrow.

        label (unicode): Dependency label.
        start (int): Index of start word.
        end (int): Index of end word.
        direction (unicode): Arrow direction, 'left' or 'right'.
        i (int): Unique ID, typically arrow index.
        RETURNS (unicode): Rendered SVG markup.
        """
        level = self.levels.index(end-start)+1
        x_start = self.offset_x+start*self.distance+self.arrow_spacing
        y = self.offset_y
        x_end = (self.offset_x+(end-start)*self.distance+start*self.distance
                 -self.arrow_spacing*(self.highest_level-level)/4)
        y_curve = self.offset_y-level*self.distance/2
        if y_curve == 0 and len(self.levels) > 5:
            y_curve = -self.distance
        arrowhead = self.get_arrowhead(direction, x_start, y, x_end)
        arc = self.get_arc(x_start, y, y_curve, x_end)
        return TPL_DEP_ARCS.format(id=self.id, i=i, stroke=self.arrow_stroke,
                                   head=arrowhead, label=label, arc=arc)

    def get_arc(self, x_start, y, y_curve, x_end):
        """Render individual arc.

        x_start (int): X-coordinate of arrow start point.
        y (int): Y-coordinate of arrow start and end point.
        y_curve (int): Y-corrdinate of Cubic Bézier y_curve point.
        x_end (int): X-coordinate of arrow end point.
        RETURNS (unicode): Definition of the arc path ('d' attribute).
        """
        template = "M{x},{y} C{x},{c} {e},{c} {e},{y}"
        if self.compact:
            template = "M{x},{y} {x},{c} {e},{c} {e},{y}"
        return template.format(x=x_start, y=y, c=y_curve, e=x_end)

    def get_arrowhead(self, direction, x, y, end):
        """Render individual arrow head.

        direction (unicode): Arrow direction, 'left' or 'right'.
        x (int): X-coordinate of arrow start point.
        y (int): Y-coordinate of arrow start and end point.
        end (int): X-coordinate of arrow end point.
        RETURNS (unicode): Definition of the arrow head path ('d' attribute).
        """
        if direction is 'left':
            pos1, pos2, pos3 = (x, x-self.arrow_width+2, x+self.arrow_width-2)
        else:
            pos1, pos2, pos3 = (end, end+self.arrow_width-2, end-self.arrow_width+2)
        arrowhead = (pos1, y+2, pos2, y-self.arrow_width, pos3, y-self.arrow_width)
        return "M{},{} L{},{} {},{}".format(*arrowhead)

    def get_levels(self, arcs):
        """Calculate available arc height "levels".
        Used to calculate arrow heights dynamically and without wasting space.

        args (list): Individual arcs and their start, end, direction and label.
        RETURNS (list): Arc levels sorted from lowest to highest.
        """
        levels = set(map(lambda arc: arc['end'] - arc['start'], arcs))
        return sorted(list(levels))


class EntityRenderer(object):
    """Render named entities as HTML."""
    style = 'ent'

    def __init__(self, options={}):
        """Initialise dependency renderer.

        options (dict): Visualiser-specific options (colors, ents)
        """
        colors = {'org': '#7aecec', 'product': '#bfeeb7', 'gpe': '#feca74',
                  'loc': '#ff9561', 'person': '#9886fc', 'norp': '#c887fb',
                  'facility': '#9cc9cc', 'event': '#ffeb80', 'language': '#ff8197',
                  'work_of_art': '#f0d0ff', 'date': '#bfe1d9', 'time': '#bfe1d9',
                  'money': '#e4e7d2', 'quantity': '#e4e7d2', 'ordinal': '#e4e7d2',
                  'cardinal': '#e4e7d2', 'percent': '#e4e7d2'}
        colors.update(options.get('colors', {}))
        self.default_color = '#ddd'
        self.colors = colors
        self.ents = options.get('ents', None)

    def render(self, parsed, page=False, minify=False):
        """Render complete markup.

        parsed (list): Dependency parses to render.
        page (bool): Render parses wrapped as full HTML page.
        minify (bool): Minify HTML markup.
        RETURNS (unicode): Rendered HTML markup.
        """
        rendered = [self.render_ents(p['text'], p['ents'], p['title']) for p in parsed]
        if page:
            docs = ''.join([TPL_FIGURE.format(content=doc) for doc in rendered])
            markup = TPL_PAGE.format(content=docs)
        else:
            markup = ''.join(rendered)
        if minify:
            return minify_html(markup)
        return markup

    def render_ents(self, text, spans, title):
        """Render entities in text.

        text (unicode): Original text.
        spans (list): Individual entity spans and their start, end and label.
        title (unicode or None): Document title set in Doc.user_data['title'].
        """
        markup = ''
        offset = 0
        for span in spans:
            label = span['label']
            start = span['start']
            end = span['end']
            entity = text[start:end]
            fragments = text[offset:start].split('\n')
            for i, fragment in enumerate(fragments):
                markup += fragment
                if len(fragments) > 1 and i != len(fragments)-1:
                    markup += '</br>'
            if self.ents is None or label.lower() in self.ents:
                color = self.colors.get(label.lower(), self.default_color)
                markup += TPL_ENT.format(label=label, text=entity, bg=color)
            else:
                markup += entity
            offset = end
        markup += text[offset:]
        markup = TPL_ENTS.format(content=markup, colors=self.colors)
        if title:
            markup = TPL_TITLE.format(title=title) + markup
        return markup