bazarr/libs/pysubs2/substation.py
2022-11-07 13:08:27 -05:00

330 lines
13 KiB
Python

import logging
import re
from numbers import Number
from .formatbase import FormatBase
from .ssaevent import SSAEvent
from .ssastyle import SSAStyle
from .common import Color
from .time import make_time, ms_to_times, timestamp_to_ms, TIMESTAMP, TIMESTAMP_SHORT
SSA_ALIGNMENT = (1, 2, 3, 9, 10, 11, 5, 6, 7)
def ass_to_ssa_alignment(i):
return SSA_ALIGNMENT[i-1]
def ssa_to_ass_alignment(i):
return SSA_ALIGNMENT.index(i) + 1
SECTION_HEADING = re.compile(
r"^.{,3}" # allow 3 chars at start of line for BOM
r"\[" # open square bracket
r"[^]]*[a-z][^]]*" # inside square brackets, at least one lowercase letter (this guards vs. uuencoded font data)
r"]" # close square bracket
)
FONT_FILE_HEADING = re.compile(r"fontname:\s+(\S+)")
STYLE_FORMAT_LINE = {
"ass": "Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic,"
" Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment,"
" MarginL, MarginR, MarginV, Encoding",
"ssa": "Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, TertiaryColour, BackColour, Bold, Italic,"
" BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, AlphaLevel, Encoding"
}
STYLE_FIELDS = {
"ass": ["fontname", "fontsize", "primarycolor", "secondarycolor", "outlinecolor", "backcolor", "bold", "italic",
"underline", "strikeout", "scalex", "scaley", "spacing", "angle", "borderstyle", "outline", "shadow",
"alignment", "marginl", "marginr", "marginv", "encoding"],
"ssa": ["fontname", "fontsize", "primarycolor", "secondarycolor", "tertiarycolor", "backcolor", "bold", "italic",
"borderstyle", "outline", "shadow", "alignment", "marginl", "marginr", "marginv", "alphalevel", "encoding"]
}
EVENT_FORMAT_LINE = {
"ass": "Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text",
"ssa": "Format: Marked, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text"
}
EVENT_FIELDS = {
"ass": ["layer", "start", "end", "style", "name", "marginl", "marginr", "marginv", "effect", "text"],
"ssa": ["marked", "start", "end", "style", "name", "marginl", "marginr", "marginv", "effect", "text"]
}
#: Largest timestamp allowed in SubStation, ie. 9:59:59.99.
MAX_REPRESENTABLE_TIME = make_time(h=10) - 10
def color_to_ass_rgba(c: Color) -> str:
return "&H%08X" % ((c.a << 24) | (c.b << 16) | (c.g << 8) | c.r)
def color_to_ssa_rgb(c: Color) -> str:
return "%d" % ((c.b << 16) | (c.g << 8) | c.r)
def rgba_to_color(s: str) -> Color:
if s[0] == '&':
x = int(s[2:], base=16)
else:
x = int(s)
r = x & 0xff
g = (x >> 8) & 0xff
b = (x >> 16) & 0xff
a = (x >> 24) & 0xff
return Color(r, g, b, a)
def is_valid_field_content(s: str) -> bool:
"""
Returns True if string s can be stored in a SubStation field.
Fields are written in CSV-like manner, thus commas and/or newlines
are not acceptable in the string.
"""
return "\n" not in s and "," not in s
def parse_tags(text, style=SSAStyle.DEFAULT_STYLE, styles={}):
"""
Split text into fragments with computed SSAStyles.
Returns list of tuples (fragment, style), where fragment is a part of text
between two brace-delimited override sequences, and style is the computed
styling of the fragment, ie. the original style modified by all override
sequences before the fragment.
Newline and non-breakable space overrides are left as-is.
Supported override tags:
- i, b, u, s
- r (with or without style name)
"""
fragments = SSAEvent.OVERRIDE_SEQUENCE.split(text)
if len(fragments) == 1:
return [(text, style)]
def apply_overrides(all_overrides):
s = style.copy()
for tag in re.findall(r"\\[ibusp][0-9]|\\r[a-zA-Z_0-9 ]*", all_overrides):
if tag == r"\r":
s = style.copy() # reset to original line style
elif tag.startswith(r"\r"):
name = tag[2:]
if name in styles:
s = styles[name].copy() # reset to named style
else:
if "i" in tag: s.italic = "1" in tag
elif "b" in tag: s.bold = "1" in tag
elif "u" in tag: s.underline = "1" in tag
elif "s" in tag: s.strikeout = "1" in tag
elif "p" in tag:
try:
scale = int(tag[2:])
except (ValueError, IndexError):
continue
s.drawing = scale > 0
return s
overrides = SSAEvent.OVERRIDE_SEQUENCE.findall(text)
overrides_prefix_sum = ["".join(overrides[:i]) for i in range(len(overrides) + 1)]
computed_styles = map(apply_overrides, overrides_prefix_sum)
return list(zip(fragments, computed_styles))
NOTICE = "Script generated by pysubs2\nhttps://pypi.python.org/pypi/pysubs2"
class SubstationFormat(FormatBase):
"""SubStation Alpha (ASS, SSA) subtitle format implementation"""
@staticmethod
def ms_to_timestamp(ms: int) -> str:
"""Convert ms to 'H:MM:SS.cc'"""
# XXX throw on overflow/underflow?
if ms < 0: ms = 0
if ms > MAX_REPRESENTABLE_TIME: ms = MAX_REPRESENTABLE_TIME
h, m, s, ms = ms_to_times(ms)
return "%01d:%02d:%02d.%02d" % (h, m, s, ms//10)
@classmethod
def guess_format(cls, text):
"""See :meth:`pysubs2.formats.FormatBase.guess_format()`"""
if re.search(r"V4\+ Styles", text, re.IGNORECASE):
return "ass"
elif re.search(r"V4 Styles", text, re.IGNORECASE):
return "ssa"
@classmethod
def from_file(cls, subs, fp, format_, **kwargs):
"""See :meth:`pysubs2.formats.FormatBase.from_file()`"""
def string_to_field(f: str, v: str):
# Per issue #45, we should handle the case where there is extra whitespace around the values.
# Extra whitespace is removed in non-string fields where it would break the parser otherwise,
# and in font name (where it doesn't really make sense). It is preserved in Dialogue string
# fields like Text, Name and Effect (to avoid introducing unnecessary change to parser output).
if f in {"start", "end"}:
v = v.strip()
if v.startswith("-"):
# handle negative timestamps
v = v[1:]
sign = -1
else:
sign = 1
m = TIMESTAMP.match(v)
if m is None:
m = TIMESTAMP_SHORT.match(v)
if m is None:
raise ValueError("Failed to parse timestamp: {!r}".format(v))
return sign * timestamp_to_ms(m.groups())
elif "color" in f:
v = v.strip()
return rgba_to_color(v)
elif f in {"bold", "underline", "italic", "strikeout"}:
return v == "-1"
elif f in {"borderstyle", "encoding", "marginl", "marginr", "marginv", "layer", "alphalevel"}:
return int(v)
elif f in {"fontsize", "scalex", "scaley", "spacing", "angle", "outline", "shadow"}:
return float(v)
elif f == "marked":
return v.endswith("1")
elif f == "alignment":
i = int(v)
if format_ == "ass":
return i
else:
return ssa_to_ass_alignment(i)
elif f == "fontname":
return v.strip()
else:
return v
subs.info.clear()
subs.aegisub_project.clear()
subs.styles.clear()
subs.fonts_opaque.clear()
inside_info_section = False
inside_aegisub_section = False
inside_font_section = False
current_font_name = None
current_font_lines_buffer = []
for lineno, line in enumerate(fp, 1):
line = line.strip()
if SECTION_HEADING.match(line):
logging.debug("at line %d: section heading %s", lineno, line)
inside_info_section = "Info" in line
inside_aegisub_section = "Aegisub" in line
inside_font_section = "Fonts" in line
elif inside_info_section or inside_aegisub_section:
if line.startswith(";"): continue # skip comments
try:
k, v = line.split(":", 1)
if inside_info_section:
subs.info[k] = v.strip()
elif inside_aegisub_section:
subs.aegisub_project[k] = v.strip()
except ValueError:
pass
elif inside_font_section:
m = FONT_FILE_HEADING.match(line)
if current_font_name and (m or not line):
# flush last font on newline or new font name
font_data = current_font_lines_buffer[:]
subs.fonts_opaque[current_font_name] = font_data
logging.debug("at line %d: finished font definition %s", lineno, current_font_name)
current_font_lines_buffer.clear()
current_font_name = None
if m:
# start new font
font_name = m.group(1)
current_font_name = font_name
elif line:
# add non-empty line to current buffer
current_font_lines_buffer.append(line)
elif line.startswith("Style:"):
_, rest = line.split(":", 1)
buf = rest.strip().split(",")
name, raw_fields = buf[0], buf[1:] # splat workaround for Python 2.7
field_dict = {f: string_to_field(f, v) for f, v in zip(STYLE_FIELDS[format_], raw_fields)}
sty = SSAStyle(**field_dict)
subs.styles[name] = sty
elif line.startswith("Dialogue:") or line.startswith("Comment:"):
ev_type, rest = line.split(":", 1)
raw_fields = rest.strip().split(",", len(EVENT_FIELDS[format_])-1)
field_dict = {f: string_to_field(f, v) for f, v in zip(EVENT_FIELDS[format_], raw_fields)}
field_dict["type"] = ev_type
ev = SSAEvent(**field_dict)
subs.events.append(ev)
# cleanup fonts
if current_font_name:
# flush last font on EOF or new section w/o newline
font_data = current_font_lines_buffer[:]
subs.fonts_opaque[current_font_name] = font_data
logging.debug("at EOF: finished font definition %s", current_font_name)
current_font_lines_buffer.clear()
current_font_name = None
@classmethod
def to_file(cls, subs, fp, format_, header_notice=NOTICE, **kwargs):
"""See :meth:`pysubs2.formats.FormatBase.to_file()`"""
print("[Script Info]", file=fp)
for line in header_notice.splitlines(False):
print(";", line, file=fp)
subs.info["ScriptType"] = "v4.00+" if format_ == "ass" else "v4.00"
for k, v in subs.info.items():
print(k, v, sep=": ", file=fp)
if subs.aegisub_project:
print("\n[Aegisub Project Garbage]", file=fp)
for k, v in subs.aegisub_project.items():
print(k, v, sep=": ", file=fp)
def field_to_string(f, v, line):
if f in {"start", "end"}:
return cls.ms_to_timestamp(v)
elif f == "marked":
return "Marked=%d" % v
elif f == "alignment" and format_ == "ssa":
return str(ass_to_ssa_alignment(v))
elif isinstance(v, bool):
return "-1" if v else "0"
elif isinstance(v, (str, Number)):
return str(v)
elif isinstance(v, Color):
if format_ == "ass":
return color_to_ass_rgba(v)
else:
return color_to_ssa_rgb(v)
else:
raise TypeError("Unexpected type when writing a SubStation field {!r} for line {!r}".format(f, line))
print("\n[V4+ Styles]" if format_ == "ass" else "\n[V4 Styles]", file=fp)
print(STYLE_FORMAT_LINE[format_], file=fp)
for name, sty in subs.styles.items():
fields = [field_to_string(f, getattr(sty, f), sty) for f in STYLE_FIELDS[format_]]
print("Style: %s" % name, *fields, sep=",", file=fp)
if subs.fonts_opaque:
print("\n[Fonts]", file=fp)
for font_name, font_lines in sorted(subs.fonts_opaque.items()):
print("fontname: {}".format(font_name), file=fp)
for line in font_lines:
print(line, file=fp)
print(file=fp)
print("\n[Events]", file=fp)
print(EVENT_FORMAT_LINE[format_], file=fp)
for ev in subs.events:
fields = [field_to_string(f, getattr(ev, f), ev) for f in EVENT_FIELDS[format_]]
print(ev.type, end=": ", file=fp)
print(*fields, sep=",", file=fp)