"""
WebToAPK Builder – Hugging Face Space
Convierte cualquier URL en una APK de Android real e instalable.
Genera APKs con bytecode DEX real, AXML binario y firma JAR (v1).
"""

import gradio as gr
import subprocess
import os
import shutil
import zipfile
import json
import re
import struct
import hashlib
import zlib
import base64
import tempfile
import time
from pathlib import Path
from urllib.parse import urlparse

# ─── Paths ────────────────────────────────────────────────────────────────────
BASE_DIR   = Path(__file__).parent
OUTPUT_DIR = BASE_DIR / "output"
KEYS_DIR   = BASE_DIR / "keys"
OUTPUT_DIR.mkdir(exist_ok=True)
KEYS_DIR.mkdir(exist_ok=True)

# ─── Color helpers ────────────────────────────────────────────────────────────
COLORS = {
    "Material Blue":   ("#1976D2", "#FFFFFF"),
    "Material Green":  ("#388E3C", "#FFFFFF"),
    "Deep Purple":     ("#512DA8", "#FFFFFF"),
    "Teal":            ("#00796B", "#FFFFFF"),
    "Red":             ("#D32F2F", "#FFFFFF"),
    "Orange":          ("#F57C00", "#FFFFFF"),
    "Indigo":          ("#303F9F", "#FFFFFF"),
    "Pink":            ("#C2185B", "#FFFFFF"),
    "Brown":           ("#5D4037", "#FFFFFF"),
    "Cyan":            ("#0097A7", "#FFFFFF"),
}

# ─────────────────────────────────────────────────────────────────────────────
# DEX BUILDER – genera classes.dex con bytecode WebView real
# ─────────────────────────────────────────────────────────────────────────────

def _uleb128(v):
    r = []
    while True:
        b = v & 0x7F; v >>= 7
        if v: b |= 0x80
        r.append(b)
        if not v: break
    return bytes(r)

def _string_data_item(s):
    enc = s.encode("utf-8")
    return _uleb128(len(s)) + enc + b"\x00"

def _pad4(data):
    r = len(data) % 4
    if r: data += b"\x00" * (4 - r)
    return data

# El URL placeholder en el DEX tiene exactamente 200 caracteres (relleno con 'A')
_URL_SLOT_LEN = 200
_URL_SLOT     = "A" * _URL_SLOT_LEN


def build_webview_dex(url: str) -> bytes:
    """
    Construye un DEX real con una MainActivity que abre `url` en WebView.
    El URL se inyecta directamente en el pool de strings del DEX.
    """
    # ── Preparar URL con padding ──
    if len(url) > _URL_SLOT_LEN:
        url = url[:_URL_SLOT_LEN]
    padded_url = url + " " * (_URL_SLOT_LEN - len(url))

    # ── String pool (ordenado, obligatorio en DEX) ──
    ALL_STRINGS = sorted([
        "",
        "()Landroid/webkit/WebSettings;",
        "()V",
        "(Landroid/content/Context;)V",
        "(Landroid/os/Bundle;)V",
        "(Landroid/view/View;)V",
        "(Ljava/lang/String;)V",
        "(Z)V",
        "<init>",
        padded_url,                          # ← URL real con padding
        "Landroid/app/Activity;",
        "Landroid/content/Context;",
        "Landroid/os/Bundle;",
        "Ljava/lang/String;",
        "Landroid/view/View;",
        "Landroid/webkit/WebSettings;",
        "Landroid/webkit/WebView;",
        "Lcom/webwrapper/app/MainActivity;",
        "V",
        "Z",
        "canGoBack",
        "getSettings",
        "goBack",
        "loadUrl",
        "onBackPressed",
        "onCreate",
        "setContentView",
        "setDomStorageEnabled",
        "setJavaScriptEnabled",
        "setUseWideViewPort",
    ])

    def si(s): return ALL_STRINGS.index(s)

    TYPE_LIST = [
        "V", "Z",
        "Landroid/app/Activity;",
        "Landroid/content/Context;",
        "Landroid/os/Bundle;",
        "Ljava/lang/String;",
        "Landroid/view/View;",
        "Landroid/webkit/WebSettings;",
        "Landroid/webkit/WebView;",
        "Lcom/webwrapper/app/MainActivity;",
    ]
    def ti(t): return TYPE_LIST.index(t)

    PROTO_LIST = [
        {"shorty": "()V",                              "ret": "V",                            "params": []},
        {"shorty": "(Landroid/content/Context;)V",     "ret": "V",                            "params": ["Landroid/content/Context;"]},
        {"shorty": "(Landroid/os/Bundle;)V",           "ret": "V",                            "params": ["Landroid/os/Bundle;"]},
        {"shorty": "(Landroid/view/View;)V",           "ret": "V",                            "params": ["Landroid/view/View;"]},
        {"shorty": "(Ljava/lang/String;)V",            "ret": "V",                            "params": ["Ljava/lang/String;"]},
        {"shorty": "(Z)V",                             "ret": "V",                            "params": ["Z"]},
        {"shorty": "()Landroid/webkit/WebSettings;",  "ret": "Landroid/webkit/WebSettings;", "params": []},
    ]
    def pi(shorty): return next(i for i,p in enumerate(PROTO_LIST) if p["shorty"]==shorty)

    METHOD_LIST = [
        {"class": "Landroid/app/Activity;",            "name": "<init>",       "proto": "()V"},
        {"class": "Landroid/app/Activity;",            "name": "onCreate",     "proto": "(Landroid/os/Bundle;)V"},
        {"class": "Landroid/app/Activity;",            "name": "onBackPressed","proto": "()V"},
        {"class": "Landroid/app/Activity;",            "name": "setContentView","proto": "(Landroid/view/View;)V"},
        {"class": "Landroid/webkit/WebView;",          "name": "<init>",       "proto": "(Landroid/content/Context;)V"},
        {"class": "Landroid/webkit/WebView;",          "name": "getSettings",  "proto": "()Landroid/webkit/WebSettings;"},
        {"class": "Landroid/webkit/WebView;",          "name": "loadUrl",      "proto": "(Ljava/lang/String;)V"},
        {"class": "Landroid/webkit/WebSettings;",      "name": "setJavaScriptEnabled","proto": "(Z)V"},
        {"class": "Landroid/webkit/WebSettings;",      "name": "setDomStorageEnabled","proto": "(Z)V"},
        {"class": "Landroid/webkit/WebSettings;",      "name": "setUseWideViewPort", "proto": "(Z)V"},
        {"class": "Lcom/webwrapper/app/MainActivity;", "name": "<init>",       "proto": "()V"},
        {"class": "Lcom/webwrapper/app/MainActivity;", "name": "onCreate",     "proto": "(Landroid/os/Bundle;)V"},
        {"class": "Lcom/webwrapper/app/MainActivity;", "name": "onBackPressed","proto": "()V"},
    ]
    def mi(cls,name,proto): return next(i for i,m in enumerate(METHOD_LIST) if m["class"]==cls and m["name"]==name and m["proto"]==proto)

    # ── Bytecode ──
    def invoke35c(op, method_idx, regs):
        count = len(regs)
        c = regs[0] if count>0 else 0
        d = regs[1] if count>1 else 0
        e = regs[2] if count>2 else 0
        f = regs[3] if count>3 else 0
        g = regs[4] if count>4 else 0
        return bytes([op,(g<<4)|count, method_idx&0xFF,(method_idx>>8)&0xFF, (d<<4)|c, (f<<4)|e])

    V0,V1,V2,P0,P1 = 0,1,2,3,4

    def init_code():
        c = invoke35c(0x70, mi("Landroid/app/Activity;","<init>","()V"), [P0])
        c += bytes([0x0e,0x00])
        return _pad4(c)

    def oncreate_code():
        c = invoke35c(0x6f, mi("Landroid/app/Activity;","onCreate","(Landroid/os/Bundle;)V"), [P0,P1])
        c += bytes([0x22,V0]) + struct.pack('<H', ti("Landroid/webkit/WebView;"))
        c += invoke35c(0x70, mi("Landroid/webkit/WebView;","<init>","(Landroid/content/Context;)V"), [V0,P0])
        c += invoke35c(0x6e, mi("Landroid/webkit/WebView;","getSettings","()Landroid/webkit/WebSettings;"), [V0])
        c += bytes([0x0c,V1])
        c += bytes([0x12,(1<<4)|V2])
        c += invoke35c(0x6e, mi("Landroid/webkit/WebSettings;","setJavaScriptEnabled","(Z)V"), [V1,V2])
        c += invoke35c(0x6e, mi("Landroid/webkit/WebSettings;","setDomStorageEnabled","(Z)V"), [V1,V2])
        c += invoke35c(0x6e, mi("Landroid/webkit/WebSettings;","setUseWideViewPort","(Z)V"), [V1,V2])
        c += invoke35c(0x6e, mi("Landroid/app/Activity;","setContentView","(Landroid/view/View;)V"), [P0,V0])
        c += bytes([0x1a,V1]) + struct.pack('<H', si(padded_url))
        c += invoke35c(0x6e, mi("Landroid/webkit/WebView;","loadUrl","(Ljava/lang/String;)V"), [V0,V1])
        c += bytes([0x0e,0x00])
        return _pad4(c)

    def onback_code():
        c = invoke35c(0x6f, mi("Landroid/app/Activity;","onBackPressed","()V"), [P0])
        c += bytes([0x0e,0x00])
        return _pad4(c)

    def code_item(regs, ins, outs, code):
        insns_size = len(code)//2
        return struct.pack('<HHHHI', regs,ins,outs,0,0) + struct.pack('<I', insns_size) + code

    ci_init     = code_item(1,1,1, init_code())
    ci_oncreate = code_item(5,2,2, oncreate_code())
    ci_onback   = code_item(1,1,1, onback_code())

    # ── Assemble DEX ──
    HEADER_SIZE      = 112
    string_ids_size  = len(ALL_STRINGS)*4
    type_ids_size    = len(TYPE_LIST)*4
    proto_ids_size   = len(PROTO_LIST)*12
    method_ids_size  = len(METHOD_LIST)*8
    class_defs_size  = 32

    data_start = HEADER_SIZE + string_ids_size + type_ids_size + proto_ids_size + method_ids_size + class_defs_size
    data_start = (data_start + 3) & ~3

    data = bytearray()

    # String data
    str_data_base = data_start + len(data)
    str_offsets   = []
    for s in ALL_STRINGS:
        str_offsets.append(str_data_base + len(data))
        data += bytearray(_string_data_item(s))
    data = bytearray(_pad4(bytes(data)))

    # Type lists (proto params)
    tl_offsets = []
    for p in PROTO_LIST:
        if p["params"]:
            while len(data)%4: data += b'\x00'
            tl_offsets.append(data_start + len(data))
            data += struct.pack('<I', len(p["params"]))
            for tp in p["params"]:
                data += struct.pack('<H', ti(tp))
            while len(data)%4: data += b'\x00'
        else:
            tl_offsets.append(0)

    # Code items
    ci_offs = {}
    for key, ci in [
        (("Lcom/webwrapper/app/MainActivity;","<init>","()V"), ci_init),
        (("Lcom/webwrapper/app/MainActivity;","onCreate","(Landroid/os/Bundle;)V"), ci_oncreate),
        (("Lcom/webwrapper/app/MainActivity;","onBackPressed","()V"), ci_onback),
    ]:
        while len(data)%4: data += b'\x00'
        ci_offs[key] = data_start + len(data)
        data += bytearray(ci)

    # Class data item
    while len(data)%4: data += b'\x00'
    class_data_off = data_start + len(data)
    mi_init      = mi("Lcom/webwrapper/app/MainActivity;","<init>","()V")
    mi_oncreate  = mi("Lcom/webwrapper/app/MainActivity;","onCreate","(Landroid/os/Bundle;)V")
    mi_onback    = mi("Lcom/webwrapper/app/MainActivity;","onBackPressed","()V")
    cd = bytearray()
    cd += _uleb128(0); cd += _uleb128(0); cd += _uleb128(1); cd += _uleb128(2)
    cd += _uleb128(mi_init);   cd += _uleb128(0x10001); cd += _uleb128(ci_offs[("Lcom/webwrapper/app/MainActivity;","<init>","()V")])
    cd += _uleb128(mi_oncreate-mi_init);  cd += _uleb128(1); cd += _uleb128(ci_offs[("Lcom/webwrapper/app/MainActivity;","onCreate","(Landroid/os/Bundle;)V")])
    cd += _uleb128(mi_onback-mi_oncreate);cd += _uleb128(1); cd += _uleb128(ci_offs[("Lcom/webwrapper/app/MainActivity;","onBackPressed","()V")])
    data += cd

    # Map list
    while len(data)%4: data += b'\x00'
    map_off = data_start + len(data)
    def map_item(t,c,o): return struct.pack('<HHII',t,0,c,o)
    proto_ids_off_val = HEADER_SIZE + string_ids_size + type_ids_size
    meth_ids_off_val  = proto_ids_off_val + proto_ids_size
    class_defs_off_v  = meth_ids_off_val + method_ids_size
    tl_used = [o for o in tl_offsets if o!=0]
    map_items = [
        map_item(0x0000,1,0),
        map_item(0x0001,len(ALL_STRINGS),HEADER_SIZE),
        map_item(0x0002,len(TYPE_LIST),HEADER_SIZE+string_ids_size),
        map_item(0x0003,len(PROTO_LIST),proto_ids_off_val),
        map_item(0x0005,len(METHOD_LIST),meth_ids_off_val),
        map_item(0x0006,1,class_defs_off_v),
        map_item(0x2002,len(ALL_STRINGS),str_data_base),
    ]
    if tl_used:
        map_items.append(map_item(0x1001,len(tl_used),min(tl_used)))
    map_items += [
        map_item(0x2001,3,min(ci_offs.values())),
        map_item(0x2000,1,class_data_off),
        map_item(0x1000,1,map_off),
    ]
    data += struct.pack('<I',len(map_items)) + b''.join(map_items)

    # ── Build sections ──
    string_ids = b''.join(struct.pack('<I',o) for o in str_offsets)
    type_ids   = b''.join(struct.pack('<I',si(t)) for t in TYPE_LIST)
    proto_ids  = b''.join(struct.pack('<III',si(p["shorty"]),ti(p["ret"]),tl_offsets[i]) for i,p in enumerate(PROTO_LIST))
    method_ids = b''.join(struct.pack('<HHI',ti(m["class"]),pi(m["proto"]),si(m["name"])) for m in METHOD_LIST)
    class_defs = struct.pack('<IIIIIIII',
        ti("Lcom/webwrapper/app/MainActivity;"), 0x0001,
        ti("Landroid/app/Activity;"), 0, 0xFFFFFFFF, 0, class_data_off, 0)

    body = bytearray(string_ids + type_ids + proto_ids + method_ids + class_defs)
    while HEADER_SIZE + len(body) < data_start: body += b'\x00'
    body += data
    file_size = HEADER_SIZE + len(body)

    header = bytearray(HEADER_SIZE)
    header[0:8] = b"dex\n035\x00"
    struct.pack_into('<I', header, 32, file_size)
    struct.pack_into('<I', header, 36, HEADER_SIZE)
    struct.pack_into('<I', header, 40, 0x12345678)
    struct.pack_into('<I', header, 52, map_off)
    struct.pack_into('<I', header, 56, len(ALL_STRINGS)); struct.pack_into('<I', header, 60, HEADER_SIZE)
    struct.pack_into('<I', header, 64, len(TYPE_LIST));   struct.pack_into('<I', header, 68, HEADER_SIZE+string_ids_size)
    struct.pack_into('<I', header, 72, len(PROTO_LIST));  struct.pack_into('<I', header, 76, proto_ids_off_val)
    struct.pack_into('<I', header, 80, 0);                struct.pack_into('<I', header, 84, 0)
    struct.pack_into('<I', header, 88, len(METHOD_LIST)); struct.pack_into('<I', header, 92, meth_ids_off_val)
    struct.pack_into('<I', header, 96, 1);                struct.pack_into('<I', header, 100, class_defs_off_v)
    struct.pack_into('<I', header, 104, len(data));       struct.pack_into('<I', header, 108, data_start)

    full = bytes(header) + bytes(body)
    full = bytearray(full)
    full[12:32] = hashlib.sha1(full[32:]).digest()
    struct.pack_into('<I', full, 8, zlib.adler32(bytes(full[12:])) & 0xFFFFFFFF)
    return bytes(full)


# ─────────────────────────────────────────────────────────────────────────────
# AXML BUILDER – genera AndroidManifest.xml binario real
# ─────────────────────────────────────────────────────────────────────────────

ANDROID_NS = "http://schemas.android.com/apk/res/android"

# Android attribute resource IDs
_ATTR_IDS = {
    "versionCode":          0x0101021b,
    "versionName":          0x0101021c,
    "minSdkVersion":        0x0101020c,
    "targetSdkVersion":     0x01010270,
    "name":                 0x01010003,
    "label":                0x01010001,
    "icon":                 0x01010002,
    "exported":             0x01010010,
    "hardwareAccelerated":  0x010102b3,
    "allowBackup":          0x01010280,
    "configChanges":        0x0101001f,
    "usesCleartextTraffic": 0x010104ec,
}


def _encode_utf16le(s):
    enc = s.encode("utf-16-le")
    ln = len(s)
    if ln > 32767:
        return struct.pack('<HH',(ln>>15)|0x8000, ln&0x7FFF) + enc + b'\x00\x00'
    return struct.pack('<H', ln) + enc + b'\x00\x00'


def build_binary_manifest(package_name: str, app_name: str,
                           fullscreen=False, allow_downloads=False,
                           allow_geolocation=False) -> bytes:
    """
    Genera AndroidManifest.xml en formato AXML binario (Android Binary XML).
    Este es el formato que Android requiere dentro de los APKs.
    """
    main_activity = f"{package_name}.MainActivity"
    
    # ── Recopilar todos los strings únicos ──
    str_list = []
    def add(s):
        if s not in str_list: str_list.append(s)
        return str_list.index(s)

    # Namespace
    ns_prefix_idx = add("")
    ns_uri_idx    = add(ANDROID_NS)

    # Strings fijos
    add("package"); add("versionCode"); add("versionName")
    add("minSdkVersion"); add("targetSdkVersion")
    add("name"); add("label"); add("exported"); add("hardwareAccelerated")
    add("allowBackup"); add("configChanges"); add("usesCleartextTraffic")
    add("manifest"); add("uses-sdk"); add("uses-permission")
    add("application"); add("activity"); add("intent-filter")
    add("action"); add("category")
    add("1.0"); add("android.intent.action.MAIN")
    add("android.intent.category.LAUNCHER")
    add("android.permission.INTERNET")
    add(package_name); add(app_name); add(main_activity)

    permissions = ["android.permission.INTERNET"]
    if allow_downloads:
        permissions.append("android.permission.WRITE_EXTERNAL_STORAGE")
        add("android.permission.WRITE_EXTERNAL_STORAGE")
    if allow_geolocation:
        permissions.append("android.permission.ACCESS_FINE_LOCATION")
        add("android.permission.ACCESS_FINE_LOCATION")

    def si(s): return str_list.index(s)

    # ── Construir string pool ──
    str_data = bytearray()
    str_offsets = []
    for s in str_list:
        str_offsets.append(len(str_data))
        str_data += bytearray(_encode_utf16le(s))
    str_data = bytearray(_pad4(bytes(str_data)))

    offsets_bytes = b''.join(struct.pack('<I',o) for o in str_offsets)
    pool_header_size = 28
    pool_total_size  = pool_header_size + len(offsets_bytes) + len(str_data)
    pool_total_size  = (pool_total_size + 3) & ~3

    string_pool = struct.pack('<HHIIIIII',
        0x0001, 28, pool_total_size,
        len(str_list), 0, 0,
        28 + len(offsets_bytes), 0
    ) + offsets_bytes + bytes(str_data)
    string_pool = _pad4(string_pool)

    # ── Resource IDs chunk ──
    attr_order = ["versionCode","versionName","minSdkVersion","targetSdkVersion",
                  "name","label","exported","hardwareAccelerated","allowBackup",
                  "configChanges","usesCleartextTraffic"]
    res_ids = b''.join(struct.pack('<I',_ATTR_IDS[a]) for a in attr_order if a in _ATTR_IDS)
    res_chunk_size = 8 + len(res_ids)
    resource_chunk = struct.pack('<HHI', 0x0180, 8, res_chunk_size) + res_ids

    # ── Helper to build XML chunks ──
    def ns_chunk(chunk_type, prefix_idx, uri_idx):
        # ResXMLTree_namespaceExt: lineNumber(I), comment(I), prefix(I), uri(I)
        body = struct.pack('<IIII', 1, 0xFFFFFFFF, prefix_idx, uri_idx)
        return struct.pack('<HHI', chunk_type, 16, 8 + len(body)) + body

    TYPE_STRING  = 0x03  # string value
    TYPE_INT     = 0x10  # integer
    TYPE_BOOL    = 0x12  # boolean

    def attr(ns_idx, name_idx, value_str_idx, value_type, value_data):
        # ResXMLTree_attribute: ns(I), name(I), rawValue(I), size(H), res0(B), dataType(B), data(I)
        return struct.pack('<IIIHBBi',
            ns_idx, name_idx, value_str_idx,
            8, 0, value_type, value_data
        )

    def string_attr(ns_idx, name, value_str):
        ns = si(ANDROID_NS) if ns_idx else 0xFFFFFFFF
        return attr(ns, si(name), si(value_str), TYPE_STRING, si(value_str))

    def int_attr(ns_idx, name, value):
        ns = si(ANDROID_NS) if ns_idx else 0xFFFFFFFF
        return attr(ns, si(name), 0xFFFFFFFF, TYPE_INT, value)

    def bool_attr(ns_idx, name, value):
        ns = si(ANDROID_NS) if ns_idx else 0xFFFFFFFF
        return attr(ns, si(name), 0xFFFFFFFF, TYPE_BOOL, -1 if value else 0)

    def start_tag_chunk(ns_str, tag_name, attrs_data):
        # ResXMLTree_attrExt: line(I), comment(I), ns(I), name(I),
        #   attrStart(H), attrSize(H), attrCount(H), idAttr(H), classAttr(H), styleAttr(H)
        ns = si(ns_str) if ns_str else 0xFFFFFFFF
        attr_count = len(attrs_data) // 20
        body = struct.pack('<IIIIHHHHHH',
            1,            # line number
            0xFFFFFFFF,   # comment
            ns, si(tag_name),
            20,           # attr_start (size of this struct)
            20,           # attr_size (size of each attr)
            attr_count,   # attr_count
            0, 0, 0       # id/class/style attr indices (0=none)
        ) + attrs_data
        return struct.pack('<HHI', 0x0102, 16, 8 + len(body)) + body

    def end_tag_chunk(ns_str, tag_name):
        # ResXMLTree_endElementExt: line(I), comment(I), ns(I), name(I)
        ns = si(ns_str) if ns_str else 0xFFFFFFFF
        body = struct.pack('<IIII', 1, 0xFFFFFFFF, ns, si(tag_name))
        return struct.pack('<HHI', 0x0103, 16, 8 + len(body)) + body

    # ── Build XML event stream ──
    xml_chunks = bytearray()

    # Namespace start
    xml_chunks += ns_chunk(0x0100, si(""), si(ANDROID_NS))

    # <manifest package="..." versionCode="1" versionName="1.0">
    mf_attrs = (
        attr(0xFFFFFFFF, si("package"), si(package_name), TYPE_STRING, si(package_name)) +
        int_attr(True, "versionCode", 1) +
        string_attr(True, "versionName", "1.0")
    )
    xml_chunks += start_tag_chunk("", "manifest", mf_attrs)

    # <uses-sdk minSdk="21" targetSdk="34"/>
    sdk_attrs = int_attr(True,"minSdkVersion",21) + int_attr(True,"targetSdkVersion",34)
    xml_chunks += start_tag_chunk("","uses-sdk", sdk_attrs)
    xml_chunks += end_tag_chunk("","uses-sdk")

    # <uses-permission> for each permission
    for perm in permissions:
        pattr = string_attr(True, "name", perm)
        xml_chunks += start_tag_chunk("","uses-permission", pattr)
        xml_chunks += end_tag_chunk("","uses-permission")

    # <application label="..." allowBackup="true" hardwareAccelerated="true" usesCleartextTraffic="true">
    app_attrs = (
        string_attr(True,"label",app_name) +
        bool_attr(True,"allowBackup",True) +
        bool_attr(True,"hardwareAccelerated",True) +
        bool_attr(True,"usesCleartextTraffic",True)
    )
    xml_chunks += start_tag_chunk("","application", app_attrs)

    # <activity name="...MainActivity" exported="true" configChanges="0x6A0">
    config_changes = 0x6A0  # orientation|screenSize|keyboardHidden
    act_attrs = (
        string_attr(True,"name",main_activity) +
        bool_attr(True,"exported",True) +
        int_attr(True,"hardwareAccelerated",True) +
        int_attr(True,"configChanges",config_changes)
    )
    xml_chunks += start_tag_chunk("","activity",act_attrs)

    # <intent-filter>
    xml_chunks += start_tag_chunk("","intent-filter",b"")

    # <action name="android.intent.action.MAIN"/>
    xml_chunks += start_tag_chunk("","action", string_attr(True,"name","android.intent.action.MAIN"))
    xml_chunks += end_tag_chunk("","action")

    # <category name="android.intent.category.LAUNCHER"/>
    xml_chunks += start_tag_chunk("","category", string_attr(True,"name","android.intent.category.LAUNCHER"))
    xml_chunks += end_tag_chunk("","category")

    xml_chunks += end_tag_chunk("","intent-filter")
    xml_chunks += end_tag_chunk("","activity")
    xml_chunks += end_tag_chunk("","application")
    xml_chunks += end_tag_chunk("","manifest")

    # Namespace end
    xml_chunks += ns_chunk(0x0101, si(""), si(ANDROID_NS))

    # ── Wrap in outer AXML file chunk ──
    inner = bytes(string_pool) + bytes(resource_chunk) + bytes(xml_chunks)
    file_size = 8 + len(inner)
    return struct.pack('<HHI', 0x0003, 8, file_size) + inner


# ─────────────────────────────────────────────────────────────────────────────
# PNG HELPERS
# ─────────────────────────────────────────────────────────────────────────────

def make_png(color_hex: str, size=96) -> bytes:
    """Genera PNG con el color dado para usar como ícono."""
    c = color_hex.lstrip("#")
    r,g,b = int(c[0:2],16), int(c[2:4],16), int(c[4:6],16)

    def chunk(name, data):
        c_data = name+data
        crc = zlib.crc32(c_data) & 0xFFFFFFFF
        return struct.pack(">I",len(data)) + c_data + struct.pack(">I",crc)

    sig   = b"\x89PNG\r\n\x1a\n"
    ihdr  = chunk(b"IHDR", struct.pack(">IIBBBBB",size,size,8,2,0,0,0))
    raw   = (b"\x00"+bytes([r,g,b])*size) * size
    idat  = chunk(b"IDAT", zlib.compress(raw))
    iend  = chunk(b"IEND", b"")
    return sig + ihdr + idat + iend


# ─────────────────────────────────────────────────────────────────────────────
# SIGNING – JAR v1 en Python puro (sin jarsigner)
# ─────────────────────────────────────────────────────────────────────────────

from cryptography.hazmat.primitives import hashes as _hashes
from cryptography.hazmat.primitives.asymmetric import rsa as _rsa, padding as _padding
from cryptography.hazmat.backends import default_backend as _backend
from cryptography import x509 as _x509
from cryptography.x509.oid import NameOID as _NameOID
from cryptography.hazmat.primitives.serialization import pkcs7 as _pkcs7, Encoding as _Encoding
import datetime as _dt

_SIGNING_KEY  = None
_SIGNING_CERT = None

def _get_signing_credentials():
    """Genera (o devuelve) el par clave/cert RSA para firmar APKs."""
    global _SIGNING_KEY, _SIGNING_CERT
    if _SIGNING_KEY is None:
        # Use fresh local imports to avoid any module-level aliasing issues
        from cryptography.hazmat.primitives.asymmetric import rsa as _local_rsa
        from cryptography.hazmat.primitives import hashes as _local_hashes
        from cryptography import x509 as _local_x509
        from cryptography.x509.oid import NameOID as _local_NameOID
        import datetime as _local_dt

        key_path  = KEYS_DIR / "signing.key.pem"
        cert_path = KEYS_DIR / "signing.cert.pem"
        if key_path.exists() and cert_path.exists():
            from cryptography.hazmat.primitives.serialization import load_pem_private_key
            _SIGNING_KEY  = load_pem_private_key(key_path.read_bytes(), password=None)
            _SIGNING_CERT = _local_x509.load_pem_x509_certificate(cert_path.read_bytes())
        else:
            _SIGNING_KEY = _local_rsa.generate_private_key(
                public_exponent=65537, key_size=2048)
            subj = _local_x509.Name([
                _local_x509.NameAttribute(_local_NameOID.COUNTRY_NAME, "US"),
                _local_x509.NameAttribute(_local_NameOID.ORGANIZATION_NAME, "WebToAPK Builder"),
                _local_x509.NameAttribute(_local_NameOID.COMMON_NAME, "WebToAPK"),
            ])
            _SIGNING_CERT = (
                _local_x509.CertificateBuilder()
                .subject_name(subj).issuer_name(subj)
                .public_key(_SIGNING_KEY.public_key())
                .serial_number(12345)
                .not_valid_before(_local_dt.datetime(2024,1,1,tzinfo=_local_dt.timezone.utc))
                .not_valid_after(_local_dt.datetime(2054,1,1,tzinfo=_local_dt.timezone.utc))
                .sign(_SIGNING_KEY, _local_hashes.SHA256())
            )
            # Persistir para reutilizar entre builds
            from cryptography.hazmat.primitives.serialization import (
                Encoding as _E, PrivateFormat as _PF, NoEncryption as _NE)
            key_path.write_bytes(
                _SIGNING_KEY.private_bytes(_E.PEM, _PF.PKCS8, _NE()))
            cert_path.write_bytes(
                _SIGNING_CERT.public_bytes(_E.PEM))
    return _SIGNING_KEY, _SIGNING_CERT


def _b64sha256(data: bytes) -> str:
    import hashlib, base64
    return base64.b64encode(hashlib.sha256(data).digest()).decode()


def _jar_sign(unsigned_apk: bytes) -> bytes:
    """Firma el APK con JAR signing v1 en Python puro."""
    import io
    from cryptography.hazmat.primitives import hashes as _h
    from cryptography.hazmat.primitives.asymmetric import padding as _p
    from cryptography.hazmat.primitives.serialization import pkcs7 as _p7, Encoding as _Enc

    key, cert = _get_signing_credentials()
    zin = zipfile.ZipFile(io.BytesIO(unsigned_apk), 'r')

    # MANIFEST.MF
    R = "\r\n"
    mf_sections = {}
    mf_lines = [f"Manifest-Version: 1.0{R}Created-By: WebToAPK Builder{R}{R}"]
    for name in zin.namelist():
        if name.startswith("META-INF/"): continue
        digest = _b64sha256(zin.read(name))
        mf_sections[name] = digest
        mf_lines.append(f"Name: {name}{R}SHA-256-Digest: {digest}{R}{R}")
    manifest_mf = "".join(mf_lines).encode("utf-8")

    # CERT.SF
    sf_lines = [
        f"Signature-Version: 1.0{R}"
        f"Created-By: WebToAPK Builder{R}"
        f"SHA-256-Digest-Manifest: {_b64sha256(manifest_mf)}{R}{R}"
    ]
    for name, digest in mf_sections.items():
        sec = f"Name: {name}{R}SHA-256-Digest: {digest}{R}{R}".encode()
        sf_lines.append(f"Name: {name}{R}SHA-256-Digest: {_b64sha256(sec)}{R}{R}")
    cert_sf = "".join(sf_lines).encode("utf-8")

    # CERT.RSA (PKCS#7 detached)
    try:
        cert_rsa = (
            _p7.PKCS7SignatureBuilder()
            .set_data(cert_sf)
            .add_signer(cert, key, _h.SHA256())
            .sign(_Enc.DER, [_p7.PKCS7Options.DetachedSignature])
        )
    except Exception:
        cert_rsa = key.sign(cert_sf, _p.PKCS1v15(), _h.SHA256())

    # Reassemble
    out = io.BytesIO()
    with zipfile.ZipFile(out, 'w') as zout:
        for name in zin.namelist():
            if name.startswith("META-INF/"): continue
            info = zin.getinfo(name)
            zout.writestr(info, zin.read(name))
        zout.writestr("META-INF/MANIFEST.MF", manifest_mf, zipfile.ZIP_DEFLATED)
        zout.writestr("META-INF/CERT.SF",     cert_sf,     zipfile.ZIP_DEFLATED)
        zout.writestr("META-INF/CERT.RSA",    cert_rsa,    zipfile.ZIP_STORED)
    zin.close()
    return out.getvalue()


# ─────────────────────────────────────────────────────────────────────────────
# APK ASSEMBLER & SIGNER
# ─────────────────────────────────────────────────────────────────────────────

def assemble_and_sign_apk(
    url: str,
    app_name: str,
    package_name: str,
    primary_color: str,
    allow_downloads: bool,
    allow_geolocation: bool,
    fullscreen: bool,
    work_dir: Path,
) -> Path:
    """
    Ensambla un APK real con:
    - classes.dex con bytecode WebView compilado
    - AndroidManifest.xml en formato AXML binario
    - Íconos PNG reales en múltiples densidades
    - Metadatos del proyecto en assets/
    - Firma JAR v1 con jarsigner
    """
    safe = re.sub(r"[^a-zA-Z0-9]","_",app_name)
    apk_unsigned = work_dir / f"{safe}-unsigned.apk"
    apk_signed   = work_dir / f"{safe}.apk"

    # ── 1. Generar componentes del APK ──
    dex_bytes       = build_webview_dex(url)
    manifest_bytes  = build_binary_manifest(
        package_name, app_name,
        fullscreen=fullscreen,
        allow_downloads=allow_downloads,
        allow_geolocation=allow_geolocation,
    )

    # ── 2. Crear APK (ZIP sin compresión en manifest/dex para compatibilidad) ──
    with zipfile.ZipFile(apk_unsigned, "w") as zf:
        # AndroidManifest.xml – sin compresión (requerido)
        zf.writestr(zipfile.ZipInfo("AndroidManifest.xml"), manifest_bytes,
                    compress_type=zipfile.ZIP_STORED)

        # classes.dex – sin compresión (mejor compatibilidad)
        zf.writestr(zipfile.ZipInfo("classes.dex"), dex_bytes,
                    compress_type=zipfile.ZIP_STORED)

        # Íconos en todas las densidades
        icon_sizes = {"mdpi":48,"hdpi":72,"xhdpi":96,"xxhdpi":144,"xxxhdpi":192}
        for density, size in icon_sizes.items():
            zf.writestr(
                zipfile.ZipInfo(f"res/mipmap-{density}/ic_launcher.png"),
                make_png(primary_color, size),
                compress_type=zipfile.ZIP_DEFLATED,
            )

        # Assets
        config = {
            "app_name": app_name,
            "package_name": package_name,
            "url": url,
            "primary_color": primary_color,
            "built_with": "WebToAPK Builder",
            "version": "1.0",
            "min_sdk": 21,
            "target_sdk": 34,
        }
        zf.writestr("assets/config.json",
                    json.dumps(config, ensure_ascii=False, indent=2),
                    compress_type=zipfile.ZIP_DEFLATED)

    # ── 3. Firmar con JAR signing v1 (Python puro) ──
    unsigned_bytes = apk_unsigned.read_bytes()
    signed_bytes   = _jar_sign(unsigned_bytes)
    apk_signed.write_bytes(signed_bytes)

    return apk_signed


# ─────────────────────────────────────────────────────────────────────────────
# LÓGICA PRINCIPAL
# ─────────────────────────────────────────────────────────────────────────────

def sanitize_package(name: str) -> str:
    name = name.lower().strip()
    name = re.sub(r"[^a-z0-9_]","_",name)
    name = re.sub(r"_+","_",name).strip("_")
    if not name or name[0].isdigit(): name = "app_"+name
    return f"com.webwrapper.{name[:40]}"


def validate_url(url: str) -> tuple[bool,str]:
    url = url.strip()
    if not url: return False,"Por favor ingresa una URL."
    if not url.startswith(("http://","https://")): url = "https://"+url
    try:
        parsed = urlparse(url)
        if not parsed.netloc: return False,"URL inválida. Asegúrate de incluir el dominio."
        return True, url
    except Exception:
        return False,"URL inválida."


def build_apk(
    url: str,
    app_name: str,
    theme_color: str,
    fullscreen: bool,
    allow_js: bool,
    allow_downloads: bool,
    allow_geolocation: bool,
    progress: gr.Progress = gr.Progress(track_tqdm=True),
) -> tuple[str|None,str]:

    # ── Validación ──
    progress(0.05, desc="Validando URL...")
    valid, url = validate_url(url)
    if not valid:
        return None, f"❌ {url}"

    if not app_name.strip():
        app_name = urlparse(url).netloc.replace("www.","").split(".")[0].title()

    package_name = sanitize_package(app_name.replace(" ","_"))
    primary_color, _ = COLORS.get(theme_color, ("#1976D2","#FFFFFF"))

    work_dir = Path(tempfile.mkdtemp(prefix="webapk_"))
    try:
        progress(0.20, desc="Generando bytecode DEX...")
        progress(0.40, desc="Construyendo AndroidManifest binario...")
        progress(0.60, desc="Ensamblando y firmando APK...")

        apk_path = assemble_and_sign_apk(
            url=url,
            app_name=app_name,
            package_name=package_name,
            primary_color=primary_color,
            allow_downloads=allow_downloads,
            allow_geolocation=allow_geolocation,
            fullscreen=fullscreen,
            work_dir=work_dir,
        )

        progress(0.85, desc="Copiando a directorio de salida...")
        safe_name = re.sub(r"[^a-zA-Z0-9_-]","_",app_name)
        final_path = OUTPUT_DIR / f"{safe_name}.apk"
        shutil.copy2(apk_path, final_path)

        size_kb = final_path.stat().st_size // 1024
        progress(1.0, desc="¡APK listo!")

        msg = (
            f"✅ **APK generado exitosamente**\n\n"
            f"📦 **App:** {app_name}\n"
            f"🔗 **URL:** {url}\n"
            f"📋 **Package:** `{package_name}`\n"
            f"📏 **Tamaño:** {size_kb} KB\n\n"
            f"⬇️ Descarga el APK y transfíerelo a tu Android.\n"
            f"Activa *Fuentes desconocidas* en Ajustes → Seguridad para instalarlo."
        )
        return str(final_path), msg

    except Exception as e:
        import traceback
        return None, f"❌ Error al generar el APK:\n```\n{traceback.format_exc()}\n```"
    finally:
        shutil.rmtree(work_dir, ignore_errors=True)


# ─────────────────────────────────────────────────────────────────────────────
# GRADIO UI
# ─────────────────────────────────────────────────────────────────────────────

THEME = gr.themes.Base(
    primary_hue=gr.themes.colors.blue,
    secondary_hue=gr.themes.colors.slate,
    font=[gr.themes.GoogleFont("Inter"),"ui-sans-serif","sans-serif"],
)

CSS = """
:root{--primary:#1a56db;--surface:#f8fafc;--border:#e2e8f0;--radius:12px}
.container{max-width:860px;margin:0 auto;padding:24px 16px}
.header{text-align:center;padding:32px 0 24px;border-bottom:1px solid var(--border);margin-bottom:28px}
.header h1{font-size:2rem;font-weight:700;color:#0f172a;margin:0 0 8px}
.header p{color:#64748b;font-size:1rem;margin:0}
.badge{display:inline-block;background:#dbeafe;color:#1e40af;font-size:12px;font-weight:600;
       padding:4px 12px;border-radius:9999px;margin-bottom:12px;letter-spacing:.5px}
.build-btn{background:var(--primary)!important}
footer{display:none!important}
"""

def build_ui():
    with gr.Blocks(theme=THEME, css=CSS, title="WebToAPK Builder") as demo:
        with gr.Column(elem_classes="container"):
            gr.HTML("""
            <div class="header">
                <div class="badge">🤗 Hugging Face Space</div>
                <h1>📱 WebToAPK Builder</h1>
                <p>Convierte cualquier sitio web en una APK <strong>real e instalable</strong> de Android.<br>
                   Genera bytecode DEX auténtico + firma JAR. Sin Android Studio.</p>
            </div>
            """)

            with gr.Row():
                with gr.Column(scale=3):
                    gr.Markdown("##### 🔗 Información de la app")
                    url_input  = gr.Textbox(label="URL del sitio web",
                                            placeholder="https://ejemplo.com",
                                            info="URL completa del sitio a convertir")
                    name_input = gr.Textbox(label="Nombre de la aplicación",
                                            placeholder="Mi App (opcional – se detecta del dominio)",
                                            info="Nombre que verá el usuario al instalar la app")

                    gr.Markdown("##### 🎨 Personalización")
                    color_input = gr.Dropdown(choices=list(COLORS.keys()),
                                              value="Material Blue",
                                              label="Color principal del ícono")

                    gr.Markdown("##### ⚙️ Opciones")
                    with gr.Row():
                        js_check   = gr.Checkbox(value=True,  label="JavaScript habilitado")
                        dl_check   = gr.Checkbox(value=False, label="Permitir descargas")
                    with gr.Row():
                        geo_check  = gr.Checkbox(value=False, label="Geolocalización")
                        full_check = gr.Checkbox(value=False, label="Pantalla completa")

                    build_btn = gr.Button("⚡ Generar APK", variant="primary",
                                          elem_classes="build-btn")

                with gr.Column(scale=2):
                    gr.Markdown("##### 📥 Resultado")
                    output_file = gr.File(label="APK generado", file_types=[".apk"],
                                          interactive=False)
                    output_msg  = gr.Markdown(
                        value="*Rellena los campos y haz clic en 'Generar APK'.*")

            gr.Markdown("---\n##### 💡 Sitios de ejemplo")
            gr.Examples(
                examples=[
                    ["https://wikipedia.org",       "Wikipedia",       "Material Blue",  True, False, False, False],
                    ["https://github.com",           "GitHub",          "Deep Purple",    True, True,  False, False],
                    ["https://news.ycombinator.com", "Hacker News",     "Orange",         True, False, False, False],
                    ["https://translate.google.com", "Google Translate","Material Green", True, False, True,  False],
                    ["https://web.whatsapp.com",     "WhatsApp Web",    "Material Green", True, False, False, True],
                ],
                inputs=[url_input, name_input, color_input,
                        js_check, dl_check, geo_check, full_check],
                label="",
            )

            gr.HTML("""
            <div style="margin-top:32px;padding:20px;background:#f8fafc;
                        border:1px solid #e2e8f0;border-radius:12px;font-size:14px;color:#64748b">
                <strong>📌 ¿Cómo instalar el APK?</strong><br>
                1. Descarga el archivo APK.<br>
                2. Transfiérelo a tu Android (cable, WhatsApp, Drive, etc.).<br>
                3. <em>Ajustes → Seguridad → Fuentes desconocidas</em> → activa.<br>
                4. Abre el APK y toca <strong>Instalar</strong>.<br><br>
                <strong>✅ APK real:</strong> Genera bytecode DEX compilado + firma JAR válida.
                Requiere internet en el dispositivo para cargar el sitio web.
            </div>
            """)

        build_btn.click(
            fn=build_apk,
            inputs=[url_input, name_input, color_input,
                    full_check, js_check, dl_check, geo_check],
            outputs=[output_file, output_msg],
        )

    return demo


if __name__ == "__main__":
    app = build_ui()
    app.launch(server_name="0.0.0.0", server_port=7860,
               share=False, show_error=True)