#!/usr/bin/env python3
"""
Generates the Material Symbols icon resources:
- include/lvgl/icons/*.h: UTF-8 string defines per icon
- include/lvgl/icons/names.h and source/icon_names.c: icon name lists per icon font
- Data/system/fonts/MaterialSymbolsRounded.ttf: TTF subset with only the used icons
- Data/system/fonts/MaterialSymbolsRounded.codepoints: name to codepoint map of the used icons

The icon fonts are rasterized from the TTF subset on device at startup.

Requires the fonttools package: pip install fonttools
"""
import os
import urllib.request
import zlib

from fontTools import subset
from fontTools.ttLib import TTFont
from fontTools.varLib import instancer

def download_file(url: str, filename: str):
    if not os.path.exists(filename):
        print(f"Downloading {filename} from {url}")
        urllib.request.urlretrieve(url, filename)
    else:
        print(f"{filename} already exists, skipping download.")

def read_code_points_map(file_path: str):
    codepoints = {}
    with open(file_path, 'r') as f:
        for line in f:
            parts = line.strip().split()
            if len(parts) >= 2:
                name, cp = parts[0].lower(), parts[1]
                codepoints[name] = cp
    if len(codepoints) == 0:
        raise ValueError(f"Code points map is empty or wasn't found at {file_path}")
    return codepoints


def get_code_points(codepoints, names: list) -> list:
    result = []
    for name in names:
        safe_name = name.lower()
        if not safe_name in codepoints:
            raise ValueError(f"Code point '{safe_name}' not found in map")
        result.append(f"0x{codepoints[safe_name].upper()}")
    return result

def generate_subset_ttf(font_file: str, codepoints: list, output_path: str) -> bytes:
    print(f"Generating {output_path}")
    font = TTFont(font_file, recalcTimestamp=False)
    if "fvar" in font:
        # Pin all axes to their defaults, which are the outlines lv_font_conv used to render
        font = instancer.instantiateVariableFont(font, {axis.axisTag: None for axis in font["fvar"].axes})
    options = subset.Options()
    options.layout_features = []
    options.drop_tables += ["GSUB", "GPOS", "GDEF"]
    options.hinting = False
    options.notdef_outline = True
    subsetter = subset.Subsetter(options)
    subsetter.populate(unicodes=codepoints)
    subsetter.subset(font)
    os.makedirs(os.path.dirname(output_path), exist_ok=True)
    font.save(output_path)
    with open(output_path, "rb") as f:
        return f.read()

def generate_codepoints_file(codepoint_map: dict, names: list, output_path: str) -> bytes:
    print(f"Generating {output_path}")
    content = "".join(f"{name} {codepoint_map[name]}\n" for name in names)
    with open(output_path, "w") as f:
        f.write(content)
    return content.encode("utf-8")

def generate_icon_name_lists(icon_sets: list, version_input: bytes):
    version = zlib.crc32(version_input + repr(icon_sets).encode("utf-8")) & 0xFFFFFFFF

    header_path = os.path.join("include", "lvgl", "icons", "names.h")
    print(f"Generating {header_path}")
    with open(header_path, "w") as f:
        f.write("// SPDX-License-Identifier: Apache-2.0\n\n")
        f.write("#pragma once\n\n")
        f.write("#include <stddef.h>\n\n")
        f.write("#ifdef __cplusplus\nextern \"C\" {\n#endif\n\n")
        f.write("/** Changes whenever the icon TTF subset, its codepoints file or the icon name lists change */\n")
        f.write(f"#define LVGL_ICON_FONT_VERSION 0x{version:08X}u\n\n")
        f.write("// Icon names per icon font, resolved through the .codepoints file next to the TTF\n")
        for name, _ in icon_sets:
            f.write(f"extern const char* const lvgl_icon_{name}_names[];\n")
            f.write(f"extern const size_t lvgl_icon_{name}_name_count;\n\n")
        f.write("#ifdef __cplusplus\n}\n#endif\n")

    source_path = os.path.join("source", "icon_names.c")
    print(f"Generating {source_path}")
    with open(source_path, "w") as f:
        f.write("// SPDX-License-Identifier: Apache-2.0\n")
        f.write("// Generated by generate-icons.py\n\n")
        f.write("#include <lvgl/icons/names.h>\n\n")
        for name, names in icon_sets:
            f.write(f"const char* const lvgl_icon_{name}_names[] = {{\n")
            for icon_name in names:
                f.write(f"    \"{icon_name.lower()}\",\n")
            f.write("};\n\n")
            f.write(f"const size_t lvgl_icon_{name}_name_count = sizeof(lvgl_icon_{name}_names) / sizeof(lvgl_icon_{name}_names[0]);\n\n")

def generate_icon_names(codepoint_map: dict, codepoint_names: list, variable_name: str):
    filename = f"{variable_name}.h"
    print(f"Generating {filename}")
    output_path = os.path.join("include", "lvgl", "icons", filename)
    with open(output_path, 'w') as f:
        f.write("// SPDX-License-Identifier: Apache-2.0\n\n")
        f.write("#pragma once\n\n")
        for name in codepoint_names:
            safe_name = name.lower()
            if safe_name in codepoint_map:
                hex_val = codepoint_map[safe_name]
                # Convert hex to int
                val = int(hex_val, 16)
                # Convert to UTF-8 escaped string
                utf8_bytes = chr(val).encode('utf-8')
                escaped_str = "".join(f"\\x{b:02X}" for b in utf8_bytes)
                
                f.write(f'#define LVGL_ICON_{variable_name.upper()}_{safe_name.upper()} "{escaped_str}"\n')
            else:
                print(f"Warning: {safe_name} not found in codepoint map")

# --------------- Symbol Fonts ---------------

# Get more from https://fonts.google.com/icons?icon.set=Material+Symbols&icon.style=Rounded
shared_symbol_code_point_names = [
    "add",
    "apps",
    "area_chart", # System Info
    "app_registration", # App Settings app
    "calendar_month",
    "cable",
    "circle",
    "close",
    "cloud", # Web server
    "check",
    "delete",
    "devices", # Developer app
    "display_settings", # Display Settings app
    "edit_note",
    "electric_bolt", # Power (settings) app
    "folder",
    "deployed_code", # 3D cube
    "download",
    "forum", # Chat app
    "gamepad",
    "hard_disk", # System Info
    "help", # Diceware help
    "hub", # App Hub
    "info", # System Info
    "image", # Screenshot app
    "keyboard_arrow_up",
    "lightbulb",
    "language", # Globe
    "lists", # Chat app toolbar
    "list_alt", # Settings apps: opens a selection dialog
    "hourglass", # App Hub: an operation for the app is pending
    "mail",
    "menu",
    "memory", # System Info
    "mop",
    "more_vert",
    "music_note",
    "note_add",
    "palette",
    "power_settings_new", # Power off for T-Lora Pager
    "refresh", # e.g. App Hub reload button
    "search",
    "select_window_2", # System Info
    "settings",
    "toolbar", # Apps without custom icon
    "navigation", # GPS (settings) app
    "keyboard_alt", # Keyboard (settings) app
    "usb", # Power (settings) app
    "wifi", # WiFi (settings) app
    "bluetooth", # Bluetooth (settings) app
    # System menu toggles
    "wifi_off",
    "bluetooth_disabled",
    "location_on",
    "location_off",
    "terminal",
    "logo_dev",
    "camera",
    "lightstrip",
    "phone_android", # Display settings: orientation
    # Files app
    "draft",
    "description",
    "link",
    "sd_card",
    "content_copy",
    "content_cut",
    "content_paste",
    "edit",
    "play_arrow",
    "eject",
    "create_new_folder",
    # Notes app
    "save",
    "save_as",
    "folder_open",
]

# Get more from https://fonts.google.com/icons?icon.set=Material+Symbols&icon.style=Rounded
statusbar_symbol_code_point_names = [
    # Location tracking
    "location_on",
    "location_off",
    # Development server
    "cloud",
    # Low on available memory
    "memory",
    # SD Card
    "sd_card",
    "sd_card_alert",
    # Wi-Fi
    "signal_wifi_0_bar",
    "network_wifi_1_bar",
    "network_wifi_2_bar",
    "network_wifi_3_bar",
    "signal_wifi_4_bar",
    "signal_wifi_off",
    "signal_wifi_bad",
    # Battery
    "battery_android_frame_1",
    "battery_android_frame_2",
    "battery_android_frame_3",
    "battery_android_frame_4",
    "battery_android_frame_5",
    "battery_android_frame_6",
    "battery_android_frame_full",
    "battery_android_frame_bolt",
    # Bluetooth
    "bluetooth",
    "bluetooth_searching",
    "bluetooth_connected",
    "bluetooth_disabled",
    "usb",
    # Mesh networking
    "hub",
    # App Hub installing an app
    "download",
]

# Get more from https://fonts.google.com/icons?icon.set=Material+Symbols&icon.style=Rounded
launcher_symbol_code_point_names = [
    "apps",
    "folder",
    "settings"
]

# Resolve file path relative to this script so it can be executed from any CWD
base_dir = os.path.dirname(__file__)
if base_dir:
    os.chdir(base_dir)

codepoints_url = "https://github.com/google/material-design-icons/raw/refs/heads/master/variablefont/MaterialSymbolsRounded%5BFILL,GRAD,opsz,wght%5D.codepoints"
ttf_url = "https://github.com/google/material-design-icons/raw/refs/heads/master/variablefont/MaterialSymbolsRounded%5BFILL,GRAD,opsz,wght%5D.ttf"

codepoints_filename = "MaterialSymbolsRounded.codepoints"
ttf_filename = "MaterialSymbolsRounded.ttf"
subset_ttf_path = os.path.join("..", "..", "Data", "system", "fonts", "MaterialSymbolsRounded.ttf")
subset_codepoints_path = os.path.join("..", "..", "Data", "system", "fonts", "MaterialSymbolsRounded.codepoints")

download_file(codepoints_url, codepoints_filename)
download_file(ttf_url, ttf_filename)

codepoints_map_path = codepoints_filename
codepoints_map = read_code_points_map(codepoints_map_path)

icon_sets = [
    ("shared", shared_symbol_code_point_names),
    ("statusbar", statusbar_symbol_code_point_names),
    ("launcher", launcher_symbol_code_point_names),
]

for variable_name, names in icon_sets:
    generate_icon_names(codepoints_map, names, variable_name)

all_names = sorted({name.lower() for _, names in icon_sets for name in names})
all_codepoints = [int(cp, 16) for cp in get_code_points(codepoints_map, all_names)]
subset_data = generate_subset_ttf(ttf_filename, all_codepoints, subset_ttf_path)
codepoints_data = generate_codepoints_file(codepoints_map, all_names, subset_codepoints_path)
generate_icon_name_lists(icon_sets, subset_data + codepoints_data)