"""
Android Text 组件 — TextUtils, SpannableString, Html, Layout 等
方法签名完全对齐 Android SDK
"""

import html as _html
import re as _re
import sys
from typing import Any, Callable, Dict, List, Optional, Sequence, Tuple, Type, Union

from .._core import (
    Stub, AndroidOnlyError, android_context,
    resolve_android_path, to_android_path,
)


# ═══════════════════════════════════════════════════════════════
# Typeface
# ═══════════════════════════════════════════════════════════════

class Typeface(Stub):
    """Typeface — 字体"""

    NORMAL = 0
    BOLD = 1
    ITALIC = 2
    BOLD_ITALIC = 3

    DEFAULT: "Typeface" = None
    DEFAULT_BOLD: "Typeface" = None
    MONOSPACE: "Typeface" = None
    SANS_SERIF: "Typeface" = None
    SERIF: "Typeface" = None

    def __init__(self, family_name: str = "", style: int = NORMAL):
        super().__init__()
        self._family_name = family_name
        self._style = style
        self._weight = 400 if style in (self.NORMAL,) else 700

    @staticmethod
    def defaultFromStyle(style: int) -> "Typeface":
        tf = Typeface("sans-serif", style)
        return tf

    @staticmethod
    def create(family_name: str, style: int) -> "Typeface":
        return Typeface(family_name, style)

    @staticmethod
    def createFromFile(path: str) -> "Typeface":
        return Typeface("custom")

    def getStyle(self) -> int:
        return self._style

    def getWeight(self) -> int:
        return self._weight

    def isBold(self) -> bool:
        return self._style in (self.BOLD, self.BOLD_ITALIC)

    def isItalic(self) -> bool:
        return self._style in (self.ITALIC, self.BOLD_ITALIC)

    def toString(self) -> str:
        return f"Typeface({self._family_name}, style={self._style})"


# Initialize Typeface constants
Typeface.DEFAULT = Typeface("sans-serif", Typeface.NORMAL)
Typeface.DEFAULT_BOLD = Typeface("sans-serif", Typeface.BOLD)
Typeface.MONOSPACE = Typeface("monospace", Typeface.NORMAL)
Typeface.SANS_SERIF = Typeface("sans-serif", Typeface.NORMAL)
Typeface.SERIF = Typeface("serif", Typeface.NORMAL)


# ═══════════════════════════════════════════════════════════════
# TextPaint
# ═══════════════════════════════════════════════════════════════

class TextPaint(Stub):
    """TextPaint — 文本绘制画笔"""

    def __init__(self, flags: int = 0):
        super().__init__()
        self.bgColor = 0
        self.bgColorSet = False
        self.linkColor = 0xFF0000FF  # blue
        self.underlineWidth = 0.0
        self.baselineShift = 0
        self.bulletRadius = 0.0
        self.bulletGap = 0
        self.bulletColor = 0
        self.color = 0xFF000000
        self.textSize = 14.0
        self.typeface: Optional[Typeface] = Typeface.DEFAULT
        self.flags = flags
        self.antiAlias = True
        self.style = Typeface.NORMAL
        self.strokeWidth = 0.0
        self.strokeCap = "butt"
        self.strokeJoin = "miter"
        self.shadowDx = 0.0
        self.shadowDy = 0.0
        self.shadowRadius = 0.0
        self.shadowColor = 0
        self.elevation = 0.0
        self.letterSpacing = 0.0
        self.fontFeatureSettings = ""
        self.fontVariationSettings = ""

    def setUnderlineText(self, underline: bool):
        if underline:
            self.underlineWidth = 1.0
        else:
            self.underlineWidth = 0.0

    def getColor(self) -> int:
        return self.color

    def setColor(self, color: int):
        self.color = color

    def setARGB(self, a: int, r: int, g: int, b: int):
        self.color = ((a & 0xFF) << 24) | ((r & 0xFF) << 16) | ((g & 0xFF) << 8) | (b & 0xFF)

    def getTextSize(self) -> float:
        return self.textSize

    def setTextSize(self, size: float):
        self.textSize = size

    def getTypeface(self) -> Optional[Typeface]:
        return self.typeface

    def setTypeface(self, tf: Typeface):
        self.typeface = tf

    def setAntiAlias(self, aa: bool):
        self.antiAlias = aa

    def measureText(self, text: str) -> float:
        return len(text) * self.textSize * 0.5

    def toString(self) -> str:
        return f"TextPaint(size={self.textSize}, color={self.color})"


# ═══════════════════════════════════════════════════════════════
# TextUtils
# ═══════════════════════════════════════════════════════════════

class TextUtils(Stub):
    """TextUtils — 文本工具"""

    CAP_MODE_SENTENCES = 0
    CAP_MODE_WORDS = 1
    CAP_MODE_CHARACTERS = 2

    @staticmethod
    def isEmpty(str_: Optional[str]) -> bool:
        return str_ is None or len(str_) == 0

    @staticmethod
    def isBlank(str_: Optional[str]) -> bool:
        return str_ is None or str_.strip() == ""

    @staticmethod
    def equals(a: Optional[str], b: Optional[str]) -> bool:
        return a == b

    @staticmethod
    def join(delimiter: str, tokens: Sequence[str]) -> str:
        return delimiter.join(tokens)

    @staticmethod
    def split(text: str, delimiter: str) -> List[str]:
        return text.split(delimiter)

    @staticmethod
    def htmlEncode(s: str) -> str:
        return _html.escape(s, quote=True)

    @staticmethod
    def htmlDecode(s: str) -> str:
        return _html.unescape(s)

    @staticmethod
    def getReverse(s: str, start: int, end: int) -> str:
        return s[start:end][::-1]

    @staticmethod
    def substring(text: str, start: int, end: int) -> str:
        return text[start:end]

    @staticmethod
    def delimitedListToStringArray(text: str, delimiter: str, delimiter2: str = "") -> List[str]:
        if not text:
            return []
        return [t.strip() for t in text.split(delimiter)]

    @staticmethod
    def commaEllipsize(text: str, max_width: int, paint: Any,
                       one_origin: bool = False, ellipsize: bool = False) -> str:
        if len(text) <= max_width:
            return text
        return text[:max_width] + "..."

    @staticmethod
    def ellipsize(text: str, paint: Any, avail: float,
                  where: Any, ellipsis: str = "...") -> str:
        if paint and hasattr(paint, 'measureText'):
            text_width = paint.measureText(text)
            if text_width <= avail:
                return text
        max_chars = int(avail / 7) if avail else len(text) // 2
        if max_chars >= len(text):
            return text
        if str(where) == "END":
            return text[:max_chars] + ellipsis
        elif str(where) == "START":
            return ellipsis + text[-max_chars:]
        elif str(where) == "MIDDLE":
            half = max_chars // 2
            return text[:half] + ellipsis + text[-(max_chars - half):]
        return text[:max_chars] + ellipsis

    @staticmethod
    def isDigitsOnly(s: str) -> bool:
        return s.isdigit() if s else False

    @staticmethod
    def isGraphical(s: str) -> bool:
        return bool(s and s.isprintable())

    @staticmethod
    def capitalize(s: str) -> str:
        return s.capitalize()

    @staticmethod
    def trim(s: str) -> str:
        return s.strip()

    @staticmethod
    def getTrimmedLength(s: str) -> int:
        return len(s.strip())

    @staticmethod
    def stringOrEmpty(s: Optional[str]) -> str:
        return s or ""

    @staticmethod
    def copySpansFrom(source: Any, start: int, end: int, kind: type,
                      dest: Any, dest_offset: int = 0):
        pass

    @staticmethod
    def removeEmptySpans(spans: List, source: Any, kind: type) -> List:
        return [s for s in spans if s is not None]

    @staticmethod
    def expandTemplate(template: str, values: List[str]) -> str:
        result = template
        for i, v in enumerate(values):
            result = result.replace("$" + str(i + 1), v)
        return result


# ═══════════════════════════════════════════════════════════════
# Span 相关接口和基类
# ═══════════════════════════════════════════════════════════════

class Spanned(Stub):
    """Spanned 接口 — 带标记的字符串"""

    SPAN_POINT_MARK = 0
    SPAN_MARK_MARK = 1
    SPAN_POINT_POINT = 2
    SPAN_MARK_POINT = 3
    SPAN_PARAGRAPH = 3
    SPAN_INCLUSIVE_EXCLUSIVE = SPAN_MARK_POINT
    SPAN_INCLUSIVE_INCLUSIVE = SPAN_MARK_MARK
    SPAN_EXCLUSIVE_EXCLUSIVE = SPAN_POINT_POINT
    SPAN_EXCLUSIVE_INCLUSIVE = SPAN_POINT_MARK
    SPAN_COMPOSING = 256
    SPAN_USER = 0x01000000
    SPAN_USER_SHIFT = 24
    SPAN_PRIORITY = 0x0000FF00
    SPAN_PRIORITY_SHIFT = 8
    SPAN_INTERMEDIATE = 0x00100000

    def __init__(self, source: str = ""):
        super().__init__()
        self._source = source
        self._spans: Dict[Tuple[type, int], Tuple[int, int, Any]] = {}  # (type, id) -> (start, end, span_obj)

    def setSpan(self, span_obj: Any, start: int, end: int, flags: int):
        span_id = id(span_obj)
        span_type = type(span_obj)
        self._spans[(span_type, span_id)] = (start, end, span_obj)

    def removeSpan(self, span_obj: Any):
        span_id = id(span_obj)
        span_type = type(span_obj)
        self._spans.pop((span_type, span_id), None)

    def getSpans(self, start: int, end: int, span_type: Optional[type] = None) -> List[Any]:
        result = []
        for (st, sid), (s, e, obj) in self._spans.items():
            if span_type is None or st == span_type:
                if s < end and e > start:
                    result.append(obj)
        return result

    def getSpanStart(self, span_obj: Any) -> int:
        span_id = id(span_obj)
        span_type = type(span_obj)
        data = self._spans.get((span_type, span_id))
        return data[0] if data else -1

    def getSpanEnd(self, span_obj: Any) -> int:
        span_id = id(span_obj)
        span_type = type(span_obj)
        data = self._spans.get((span_type, span_id))
        return data[1] if data else -1

    def getSpanFlags(self, span_obj: Any) -> int:
        span_id = id(span_obj)
        span_type = type(span_obj)
        data = self._spans.get((span_type, span_id))
        return 0 if data is None else 0

    def nextSpanTransition(self, start: int, end: int, span_type: Optional[type] = None) -> int:
        return end

    def toString(self) -> str:
        return self._source

    def __len__(self) -> int:
        return len(self._source)

    def __getitem__(self, index):
        return self._source[index]

    def __str__(self):
        return self._source

    def length(self) -> int:
        return len(self._source)


class Editable(Spanned):
    """Editable — 可编辑文本接口"""

    def __init__(self, source: str = ""):
        super().__init__(source)

    def append(self, text: Any) -> "Editable":
        self._source += str(text)
        return self

    def insert(self, where: int, text: Any):
        self._source = self._source[:where] + str(text) + self._source[where:]

    def replace(self, start: int, end: int, text: Any):
        self._source = self._source[:start] + str(text) + self._source[end:]

    def delete(self, start: int, end: int):
        self._source = self._source[:start] + self._source[end:]

    def clear(self):
        self._source = ""

    def clearSpans(self):
        self._spans.clear()

    def getChars(self, start: int, end: int, dest: List[str], destoff: int):
        for i, c in enumerate(self._source[start:end]):
            if destoff + i < len(dest):
                dest[destoff + i] = c


# ═══════════════════════════════════════════════════════════════
# SpannableString
# ═══════════════════════════════════════════════════════════════

class SpannableString(Spanned):
    """SpannableString — 不可变但可标记的字符串"""

    def __init__(self, source: str):
        super().__init__(source)
        self._source = source

    def setSpan(self, span_obj: Any, start: int, end: int, flags: int):
        super().setSpan(span_obj, start, end, flags)

    def removeSpan(self, span_obj: Any):
        super().removeSpan(span_obj)

    def toString(self) -> str:
        return self._source

    def __str__(self):
        return self._source

    @staticmethod
    def valueOf(source: str) -> "SpannableString":
        return SpannableString(source)

    def length(self) -> int:
        return len(self._source)

    def charAt(self, index: int) -> str:
        return self._source[index]

    def subSequence(self, start: int, end: int) -> str:
        return self._source[start:end]


# ═══════════════════════════════════════════════════════════════
# SpannableStringBuilder
# ═══════════════════════════════════════════════════════════════

class SpannableStringBuilder(Editable):
    """SpannableStringBuilder — 可变可标记字符串构建器"""

    def __init__(self, source: Any = None):
        if source is None:
            super().__init__("")
        elif isinstance(source, str):
            super().__init__(source)
        elif isinstance(source, Spanned):
            super().__init__(source.toString())
        else:
            super().__init__(str(source))

    def append(self, text: Any) -> "SpannableStringBuilder":
        super().append(text)
        return self

    def append(self, text: Any, start: int, end: int) -> "SpannableStringBuilder":
        if isinstance(text, str):
            self._source += text[start:end]
        else:
            self._source += str(text)[start:end]
        return self

    def insert(self, where: int, text: Any) -> "SpannableStringBuilder":
        super().insert(where, text)
        return self

    def replace(self, start: int, end: int, text: Any) -> "SpannableStringBuilder":
        super().replace(start, end, text)
        return self

    def delete(self, start: int, end: int) -> "SpannableStringBuilder":
        super().delete(start, end)
        return self

    def setSpan(self, span_obj: Any, start: int, end: int, flags: int):
        super().setSpan(span_obj, start, end, flags)

    def clear(self):
        super().clear()

    def clearSpans(self):
        super().clearSpans()

    def length(self) -> int:
        return len(self._source)

    def charAt(self, index: int) -> str:
        return self._source[index] if 0 <= index < len(self._source) else ""

    def subSequence(self, start: int, end: int) -> str:
        return self._source[start:end]

    def toString(self) -> str:
        return self._source

    def __str__(self):
        return self._source

    def __iadd__(self, other: Any) -> "SpannableStringBuilder":
        self.append(str(other))
        return self


# ═══════════════════════════════════════════════════════════════
# TextWatcher
# ═══════════════════════════════════════════════════════════════

class TextWatcher(Stub):
    """TextWatcher — 文本变化监听器"""

    def beforeTextChanged(self, s: str, start: int, count: int, after: int):
        pass

    def onTextChanged(self, s: str, start: int, before: int, count: int):
        pass

    def afterTextChanged(self, s: Any):
        pass


# ═══════════════════════════════════════════════════════════════
# InputFilter / LengthFilter
# ═══════════════════════════════════════════════════════════════

class InputFilter(Stub):
    """InputFilter — 输入过滤器接口"""

    class LengthFilter(Stub):
        """LengthFilter — 长度限制过滤器"""

        def __init__(self, max_length: int):
            super().__init__()
            self._max_length = max_length

        def filter(self, source: str, start: int, end: int, dest: Spanned,
                   dstart: int, dend: int) -> Optional[str]:
            keep = self._max_length - (len(dest.toString()) - (dend - dstart))
            if keep <= 0:
                return ""
            if keep >= (end - start):
                return None  # keep original
            return source[start:start + keep]

        def getMax(self) -> int:
            return self._max_length

    @staticmethod
    def allCaps() -> "InputFilter":
        f = InputFilter()
        f._transform = lambda s: s.upper()
        return f

    def filter(self, source: str, start: int, end: int, dest: Spanned,
               dstart: int, dend: int) -> Optional[str]:
        return None


# ═══════════════════════════════════════════════════════════════
# Html
# ═══════════════════════════════════════════════════════════════

class Html(Stub):
    """Html — HTML 文本处理"""

    FROM_HTML_MODE_COMPACT = 0
    FROM_HTML_MODE_LEGACY = 1
    FROM_HTML_OPTION_USE_CSS_COLORS = 256
    FROM_HTML_SEPARATOR_LINE_BREAK_BLOCKQUOTE = 0x00000001
    FROM_HTML_SEPARATOR_LINE_BREAK_DIV = 0x00000002
    FROM_HTML_SEPARATOR_LINE_BREAK_HEADING = 0x00000004
    FROM_HTML_SEPARATOR_LINE_BREAK_LIST_ITEM = 0x00000008
    FROM_HTML_SEPARATOR_LINE_BREAK_LIST = 0x00000020
    FROM_HTML_SEPARATOR_LINE_BREAK_TABLE = 0x00000040
    TO_HTML_PARAGRAPH_LINES_INDIVIDUAL = 0x00000001
    TO_HTML_PARAGRAPH_LINE_CONSECUTIVE = 0x00000002

    _TAG_RE = _re.compile(r"<[^>]*>")
    _BR_RE = _re.compile(r"<br\s*/?\s*>", _re.IGNORECASE)
    _P_RE = _re.compile(r"</p>|<p[^>]*>", _re.IGNORECASE)

    @staticmethod
    def fromHtml(html_text: str, flags: int = 0) -> str:
        """将 HTML 转为纯文本"""
        text = html_text
        text = Html._BR_RE.sub("\n", text)
        text = Html._P_RE.sub("\n\n", text)
        text = Html._TAG_RE.sub("", text)
        text = _html.unescape(text)
        return text.strip()

    @staticmethod
    def toHtml(text: str, option: int = 0) -> str:
        """将纯文本转为 HTML"""
        paragraphs = text.split("\n")
        html_parts = []
        for p in paragraphs:
            escaped = _html.escape(p)
            html_parts.append(f"<p>{escaped}</p>")
        return "".join(html_parts)

    @staticmethod
    def fromHtml(html_text: str, image_getter: Any, tag_handler: Any) -> str:
        return Html.fromHtml(html_text)

    @staticmethod
    def toHtmlWithOptions(text: str, options: int) -> str:
        return Html.toHtml(text)

    class ImageGetter:
        def getDrawable(self, source: str):
            return None

    class TagHandler:
        def handleTag(self, opening: bool, tag: str, output: Editable, xml_reader: Any):
            pass


# ═══════════════════════════════════════════════════════════════
# CharacterStyle / 各 Span 实现
# ═══════════════════════════════════════════════════════════════

class CharacterStyle(Stub):
    """CharacterStyle — 字符样式基类"""

    def underLine(self):
        pass

    def updateDrawState(self, tp: TextPaint):
        pass

    def getUnderline(self) -> bool:
        return False

    @staticmethod
    def wrap(cs: "CharacterStyle") -> "CharacterStyle":
        return cs


class StyleSpan(CharacterStyle):
    """StyleSpan — 字体样式"""

    def __init__(self, style: int):
        super().__init__()
        self._style = style

    def getStyle(self) -> int:
        return self._style

    def updateDrawState(self, tp: TextPaint):
        tp.style = self._style


class TypefaceSpan(CharacterStyle):
    """TypefaceSpan — 字体族"""

    def __init__(self, family: str):
        super().__init__()
        self._family = family

    def getFamily(self) -> str:
        return self._family

    def updateDrawState(self, tp: TextPaint):
        if self._family == "monospace":
            tp.typeface = Typeface.MONOSPACE
        elif self._family == "serif":
            tp.typeface = Typeface.SERIF
        else:
            tp.typeface = Typeface.DEFAULT


class RelativeSizeSpan(CharacterStyle):
    """RelativeSizeSpan — 相对大小"""

    def __init__(self, size: float):
        super().__init__()
        self._size = size

    def getSizeChange(self) -> float:
        return self._size

    def updateDrawState(self, tp: TextPaint):
        tp.textSize *= self._size


class ForegroundColorSpan(CharacterStyle):
    """ForegroundColorSpan — 前景色"""

    def __init__(self, color: int):
        super().__init__()
        self._color = color

    def getForegroundColor(self) -> int:
        return self._color

    def updateDrawState(self, tp: TextPaint):
        tp.color = self._color


class BackgroundColorSpan(CharacterStyle):
    """BackgroundColorSpan — 背景色"""

    def __init__(self, color: int):
        super().__init__()
        self._color = color

    def getBackgroundColor(self) -> int:
        return self._color

    def updateDrawState(self, tp: TextPaint):
        tp.bgColor = self._color
        tp.bgColorSet = True


class UnderlineSpan(CharacterStyle):
    """UnderlineSpan — 下划线"""

    def updateDrawState(self, tp: TextPaint):
        tp.setUnderlineText(True)


class StrikethroughSpan(CharacterStyle):
    """StrikethroughSpan — 删除线"""

    def updateDrawState(self, tp: TextPaint):
        pass  # desktop 无直接等价


class SubscriptSpan(CharacterStyle):
    """SubscriptSpan — 下标"""

    def updateDrawState(self, tp: TextPaint):
        tp.baselineShift = -tp.textSize / 4


class SuperscriptSpan(CharacterStyle):
    """SuperscriptSpan — 上标"""

    def updateDrawState(self, tp: TextPaint):
        tp.baselineShift = tp.textSize / 2


class ImageSpan(CharacterStyle):
    """ImageSpan — 图片"""

    ALIGN_BOTTOM = 0
    ALIGN_BASELINE = 1
    ALIGN_CENTER = 2
    ALIGN_TOP = 3

    def __init__(self, drawable: Any, source: str = "", align: int = ALIGN_BOTTOM):
        super().__init__()
        self._drawable = drawable
        self._source = source
        self._align = align

    def getDrawable(self):
        return self._drawable

    def getSource(self) -> str:
        return self._source

    def getAlignment(self) -> int:
        return self._align


class ClickableSpan(CharacterStyle):
    """ClickableSpan — 可点击文本"""

    def __init__(self):
        super().__init__()

    def onClick(self, view: Any):
        pass

    def updateDrawState(self, tp: TextPaint):
        tp.color = tp.linkColor
        tp.setUnderlineText(True)


class URLSpan(ClickableSpan):
    """URLSpan — URL 链接"""

    def __init__(self, url: str):
        super().__init__()
        self._url = url

    def getURL(self) -> str:
        return self._url

    def onClick(self, view: Any):
        sys.stderr.write(f"[URLSpan] onClick: {self._url}\n")

    def updateDrawState(self, tp: TextPaint):
        super().updateDrawState(tp)


# ═══════════════════════════════════════════════════════════════
# NoCopySpan / ParagraphStyle 接口
# ═══════════════════════════════════════════════════════════════

class NoCopySpan(Stub):
    """NoCopySpan — 标记不在拷贝时复制的 span"""
    pass

class NoCopySpanConcise(NoCopySpan):
    """NoCopySpan.Concrete — 具体实现"""
    pass


class ParagraphStyle(Stub):
    """ParagraphStyle — 段落样式接口"""
    pass


# ═══════════════════════════════════════════════════════════════
# Ellipsize / TruncateAt 枚举
# ═══════════════════════════════════════════════════════════════

class Ellipsize(Stub):
    """Ellipsize 常量"""
    END = "END"
    MIDDLE = "MIDDLE"
    MARQUEE = "MARQUEE"
    START = "START"
    NONE = "NONE"


class TruncateAt(Stub):
    """TruncateAt 常量"""
    END = "END"
    MIDDLE = "MIDDLE"
    MARQUEE = "MARQUEE"
    START = "START"


# ═══════════════════════════════════════════════════════════════
# Align
# ═══════════════════════════════════════════════════════════════

class Align(Stub):
    """Layout.Alignment 枚举"""
    ALIGN_NORMAL = 0
    ALIGN_OPPOSITE = 1
    ALIGN_CENTER = 2


# ═══════════════════════════════════════════════════════════════
# TextDirectionHeuristic / TextDirectionHeuristics
# ═══════════════════════════════════════════════════════════════

class TextDirectionHeuristic(Stub):
    """TextDirectionHeuristic — 文本方向启发式"""
    pass


class TextDirectionHeuristics(Stub):
    """TextDirectionHeuristics — 文本方向启发式常量"""

    FIRSTSTRONG_LTR = TextDirectionHeuristic()
    FIRSTSTRONG_RTL = TextDirectionHeuristic()
    ANYRTL_LTR = TextDirectionHeuristic()
    LTR = TextDirectionHeuristic()
    RTL = TextDirectionHeuristic()
    LOCALE = TextDirectionHeuristic()


# ═══════════════════════════════════════════════════════════════
# LoginFilter
# ═══════════════════════════════════════════════════════════════

class LoginFilter(InputFilter):
    """LoginFilter — 登录名输入过滤器"""

    def __init__(self, append_ok: bool = True):
        super().__init__()
        self._append_ok = append_ok

    def isAllowed(self, c: str) -> bool:
        return c.isalnum() or c in "@._-"

    def filter(self, source: str, start: int, end: int, dest: Spanned,
               dstart: int, dend: int) -> Optional[str]:
        filtered = []
        for c in source[start:end]:
            if self.isAllowed(c):
                filtered.append(c)
            elif self._append_ok:
                pass
        result = "".join(filtered)
        return result if result != source else None

    class UsernameFilterGMail(InputFilter):
        def filter(self, source, start, end, dest, dstart, dend):
            result = []
            for c in source[start:end]:
                if c.isalnum() or c in "@._-":
                    result.append(c)
            return "".join(result) or None

    class PasswordFilterGMail(InputFilter):
        def filter(self, source, start, end, dest, dstart, dend):
            return None


# ═══════════════════════════════════════════════════════════════
# Method / MovementMethod
# ═══════════════════════════════════════════════════════════════

class Method(Stub):
    """Method — 输入法接口"""
    pass


class MovementMethod(Stub):
    """MovementMethod — 移动方式接口"""
    pass


# ═══════════════════════════════════════════════════════════════
# Layout / StaticLayout / DynamicLayout / BoringLayout
# ═══════════════════════════════════════════════════════════════

class Layout(Stub):
    """Layout — 布局基类"""

    Alignment = Align

    BREAK_STRATEGY_SIMPLE = 0
    BREAK_STRATEGY_HIGH_QUALITY = 1
    BREAK_STRATEGY_BALANCED = 2

    HYPHENATION_FREQUENCY_NONE = 0
    HYPHENATION_FREQUENCY_NORMAL = 1
    HYPHENATION_FREQUENCY_FULL = 2

    JUSTIFICATION_MODE_NONE = 0
    JUSTIFICATION_MODE_INTER_WORD = 1

    def __init__(self, text: str, paint: TextPaint, width: int, alignment: int,
                 spacing_mult: float, spacing_add: float):
        super().__init__()
        self._text = text
        self._paint = paint
        self._width = width
        self._alignment = alignment
        self._spacing_mult = spacing_mult
        self._spacing_add = spacing_add
        self._line_count = max(1, len(text) // max(1, width // 10) + 1)

    def getLineCount(self) -> int:
        return self._line_count

    def getLineBounds(self, line: int, bounds: Optional[Any]) -> int:
        line_height = int(self._paint.textSize * self._spacing_mult + self._spacing_add)
        return line * line_height

    def getPrimaryHorizontal(self, offset: int) -> float:
        line = 0
        return (offset % max(1, self._width)) * self._paint.measureText("x")

    def getSecondaryHorizontal(self, offset: int) -> float:
        return 0.0

    def getLineTop(self, line: int) -> int:
        line_height = int(self._paint.textSize * self._spacing_mult + self._spacing_add)
        return line * line_height

    def getLineBottom(self, line: int) -> int:
        line_height = int(self._paint.textSize * self._spacing_mult + self._spacing_add)
        return (line + 1) * line_height

    def getLineStart(self, line: int) -> int:
        chars_per_line = max(1, self._width // max(1, int(self._paint.measureText("x"))))
        return line * chars_per_line

    def getLineEnd(self, line: int) -> int:
        chars_per_line = max(1, self._width // max(1, int(self._paint.measureText("x"))))
        return min((line + 1) * chars_per_line, len(self._text))

    def getText(self) -> str:
        return self._text

    def getPaint(self) -> TextPaint:
        return self._paint

    def getWidth(self) -> int:
        return self._width

    def getAlignment(self) -> int:
        return self._alignment

    def getSpacingMultiplier(self) -> float:
        return self._spacing_mult

    def getSpacingAdd(self) -> float:
        return self._spacing_add

    def isRtlCharAt(self, offset: int) -> bool:
        return False

    def getParagraphDirection(self, line: int) -> int:
        return 1

    def draw(self, canvas: Any):
        pass


class StaticLayout(Layout):
    """StaticLayout — 静态布局"""

    def __init__(self, source: str, paint: TextPaint, width: int, alignment: int,
                 spacing_mult: float, spacing_add: float, include_pad: bool):
        super().__init__(source, paint, width, alignment, spacing_mult, spacing_add)
        self._include_pad = include_pad


class DynamicLayout(Layout):
    """DynamicLayout — 动态布局"""

    def __init__(self, base: Any, paint: TextPaint, width: int, alignment: int,
                 spacing_mult: float, spacing_add: float, include_pad: bool,
                 ellipsize: Any = None, ellipsize_width: int = 0):
        super().__init__(str(base), paint, width, alignment, spacing_mult, spacing_add)
        self._include_pad = include_pad


class BoringLayout(Layout):
    """BoringLayout — 单行布局"""

    def __init__(self, source: str, paint: TextPaint, width: int, alignment: int,
                 spacing_mult: float, spacing_add: float, include_pad: bool,
                 ellipsize: Any = None, ellipsize_width: int = 0):
        super().__init__(source, paint, width, alignment, spacing_mult, spacing_add)
        self._include_pad = include_pad
        self._line_count = 1 if source else 0

    class Metrics(Stub):
        """Metrics for BoringLayout"""
        width = 0
        height = 0

    @staticmethod
    def isBoring(text: str, paint: TextPaint) -> Optional["BoringLayout.Metrics"]:
        m = BoringLayout.Metrics()
        m.width = int(paint.measureText(text))
        m.height = int(paint.textSize)
        return m if text else None

    @staticmethod
    def make(source: str, paint: TextPaint, width: int, alignment: int,
             spacing_mult: float, spacing_add: float, metrics: "BoringLayout.Metrics",
             include_pad: bool) -> "BoringLayout":
        return BoringLayout(source, paint, width, alignment, spacing_mult, spacing_add, include_pad)


class ClipRectangle(Stub):
    """ClipRectangle — 裁剪矩形"""
    def __init__(self, left: int = 0, top: int = 0, right: int = 0, bottom: int = 0):
        super().__init__()
        self.left = left
        self.top = top
        self.right = right
        self.bottom = bottom


# ═══════════════════════════════════════════════════════════════
# Spannable (接口别名)
# ═══════════════════════════════════════════════════════════════

class Spannable(Spanned):
    """Spannable — 可标记接口"""
    pass


# ═══════════════════════════════════════════════════════════════
# __all__
# ═══════════════════════════════════════════════════════════════

__all__ = [
    "TextUtils",
    "SpannableString",
    "SpannableStringBuilder",
    "Spannable",
    "Editable",
    "Spanned",
    "TextWatcher",
    "InputFilter",
    "Html",
    "Layout",
    "StaticLayout",
    "DynamicLayout",
    "BoringLayout",
    "ClipRectangle",
    "TextPaint",
    "TextDirectionHeuristic",
    "TextDirectionHeuristics",
    "Align",
    "Ellipsize",
    "TruncateAt",
    "LoginFilter",
    "Method",
    "MovementMethod",
    "NoCopySpan",
    "ParagraphStyle",
    "CharacterStyle",
    "StyleSpan",
    "TypefaceSpan",
    "RelativeSizeSpan",
    "ForegroundColorSpan",
    "BackgroundColorSpan",
    "UnderlineSpan",
    "StrikethroughSpan",
    "SubscriptSpan",
    "SuperscriptSpan",
    "ImageSpan",
    "ClickableSpan",
    "URLSpan",
    "Typeface",
]