#!/usr/bin/env python3
"""Generate MiSans bitmap font C arrays for ILI9341 LCD driver."""

import glob
import math
import os
import re
import sys
from PIL import Image, ImageDraw, ImageFont

ROOT = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
HEADER_IN = os.path.join(ROOT, "device", "LCD_ILI9341", "Drv_ILI9341_Lcd_ChineseFont.h")
HEADER_OUT = HEADER_IN
ENG_HEADER_IN = os.path.join(ROOT, "device", "LCD_ILI9341", "Drv_ILI9341_Lcd_EnglishFont.h")
ENG_HEADER_OUT = ENG_HEADER_IN

MISANS_DIR = os.path.join(os.path.dirname(ROOT), "..", "Doc", "UI", "MiSans")
MISANS_DIR = os.path.normpath(MISANS_DIR)


def find_ttf(name_part):
    for path in glob.glob(os.path.join(MISANS_DIR, "**", "*.ttf"), recursive=True):
        if name_part.lower() in os.path.basename(path).lower():
            return path
    raise FileNotFoundError(f"TTF matching {name_part} not found under {MISANS_DIR}")


def parse_chs_tables(text):
    tables = {}
    for m in re.finditer(r"const char (CHS\d+Table)\[\]\[2\] = \{(.*?)\};", text, re.S):
        name = m.group(1)
        body = m.group(2)
        entries = []
        comments = []
        for line in body.splitlines():
            cm = re.search(r"\{(0x[0-9A-Fa-f]{2})\s*,\s*(0x[0-9A-Fa-f]{2})\}", line)
            if cm:
                entries.append((int(cm.group(1), 16), int(cm.group(2), 16)))
                cmt = re.search(r"//\s*(.+)", line)
                comments.append(cmt.group(1).strip() if cmt else "")
        tables[name] = list(zip(entries, comments))
    return tables


def gbk_char(h, l):
    return bytes([h, l]).decode("gbk", errors="replace")


def render_glyph(ch, size, font, square=True):
    if square:
        w = h = size
    else:
        w = size // 2
        h = size

    img = Image.new("L", (w, h), 0)
    draw = ImageDraw.Draw(img)

    bbox = draw.textbbox((0, 0), ch, font=font)
    tw = bbox[2] - bbox[0]
    th = bbox[3] - bbox[1]
    x = (w - tw) // 2 - bbox[0]
    y = (h - th) // 2 - bbox[1]
    draw.text((x, y), ch, fill=255, font=font)

    pixels = []
    for row in range(h):
        for col in range(w):
            pixels.append(1 if img.getpixel((col, row)) > 127 else 0)
    return pixels, w, h


def cn_to_bytes_msb(pixels, width, height):
    row_bytes = (width + 7) // 8
    out = []
    for row in range(height):
        for bi in range(row_bytes):
            val = 0
            for bit in range(8):
                col = bi * 8 + bit
                if col < width and pixels[row * width + col]:
                    val |= (0x80 >> bit)
                elif col >= width:
                    pass
            out.append(val)
    return out


def ascii_to_bytes_lsb(pixels, width, height):
    row_bytes = (width + 7) // 8
    out = []
    for row in range(height):
        for bi in range(row_bytes):
            val = 0
            for bit in range(8):
                col = bi * 8 + bit
                if col < width and pixels[row * width + col]:
                    val |= (0x01 << bit)
            out.append(val)
    return out


def fmt_bytes(data):
    parts = []
    for i, b in enumerate(data):
        parts.append(f"0x{b:02X}")
    lines = []
    for i in range(0, len(parts), 16):
        lines.append(",".join(parts[i:i + 16]))
    return "{" + ",".join(lines) + "}"


def generate_chinese_array(table_name, entries, size, font):
    lines = [f"const unsigned char Chinese_font_{size}[][{((size + 7)//8)*size}] = {{"]
    for idx, ((h, l), comment) in enumerate(entries):
        ch = gbk_char(h, l)
        pixels, w, hgt = render_glyph(ch, size, font, square=True)
        data = cn_to_bytes_msb(pixels, w, hgt)
        cmt = comment or ch
        lines.append(f"{fmt_bytes(data)},/*\"{cmt}\",{idx}*/")
    lines.append("};")
    return "\n".join(lines)


def generate_ascii_array(size, font, array_name=None):
    sizex = size // 2
    row_bytes = (sizex + 7) // 8
    total = row_bytes * size
    suffix = f"{size}{sizex}"
    name = array_name or f"ascii_{suffix}"
    lines = [f"const unsigned char {name}[][{total}]={{"]

    for num in range(95):
        ch = chr(num + 32)
        pixels, w, hgt = render_glyph(ch, size, font, square=False)
        data = ascii_to_bytes_lsb(pixels, w, hgt)
        lines.append(f"{fmt_bytes(data)},/*\"{ch}\",{num}*/")
    lines.append("};")
    return name, "\n".join(lines)


def patch_header_chinese(text, tables, fonts_by_size):
    # Replace each Chinese_font_XX array
    for size, font in fonts_by_size.items():
        table_key = {
            8: "CHS8Table",
            11: "CHS11Table",
            12: "CHS12Table",
            13: "CHS13Table",
            15: "CHS15Table",
            16: "CHS16Table",
            28: "CHS24Table",  # reuse 24 table chars for 28 if no CHS28
        }.get(size)

        if size == 28:
            table_key = "CHS24Table"
        if table_key not in tables:
            print(f"Skip size {size}: no {table_key}")
            continue

        entries = tables[table_key]
        new_array = generate_chinese_array(table_key, entries, size, font)

        pat = rf"const unsigned char Chinese_font_{size}\[\]\[\d+\] = \{{.*?\}};"
        if re.search(pat, text, re.S):
            text = re.sub(pat, new_array, text, count=1, flags=re.S)
        else:
            # insert before Chinese_font for next size or at end of tables section
            insert_after = f"const char {table_key}"
            # add new table for CHS8/CHS15 if missing
            pass

    return text


def ensure_chs8_table(text, tables):
    if "CHS8Table" in tables:
        return text, tables
    if "CHS12Table" not in tables:
        return text, tables
    # Insert CHS8Table copy of CHS12Table before CHS11Table
    entries = tables["CHS12Table"]
    block = "const char CHS8Table[][2] = {\n"
    for (h, l), cmt in entries:
        block += f"    {{0x{h:02X},0x{l:02X}}}, // {cmt}\n"
    block += "};\n\n"
    text = text.replace("const char CHS11Table", block + "const char CHS11Table", 1)
    tables["CHS8Table"] = entries
    return text, tables


def ensure_chs15_table(text, tables):
    if "CHS15Table" in tables:
        return text, tables
    if "CHS13Table" not in tables:
        return text, tables
    entries = tables["CHS13Table"]
    block = "const char CHS15Table[][2] = {\n"
    for (h, l), cmt in entries:
        block += f"    {{0x{h:02X},0x{l:02X}}}, // {cmt}\n"
    block += "};\n\n"
    text = text.replace("const char CHS16Table", block + "const char CHS16Table", 1)
    tables["CHS15Table"] = entries
    return text, tables


def main():
    medium = find_ttf("MiSans-Medium")
    semibold = find_ttf("MiSans-Semibold")
    print("Medium:", medium)
    print("Semibold:", semibold)

    with open(HEADER_IN, "r", encoding="utf-8", errors="replace") as f:
        text = f.read()

    tables = parse_chs_tables(text)
    print("Tables:", {k: len(v) for k, v in tables.items()})

    text, tables = ensure_chs8_table(text, tables)
    text, tables = ensure_chs15_table(text, tables)

    # Regenerate all Chinese font arrays
    cn_sizes = [8, 11, 12, 13, 15, 16, 24, 28]
    for size in cn_sizes:
        if size in (24, 28):
            table_key = "CHS24Table"
            font = ImageFont.truetype(semibold if size == 28 else medium, size - 2)
        else:
            table_key = {
                8: "CHS8Table", 11: "CHS11Table", 12: "CHS12Table",
                13: "CHS13Table", 15: "CHS15Table", 16: "CHS16Table",
            }[size]
            font = ImageFont.truetype(medium, size - 1)

        if table_key not in tables:
            continue
        entries = tables[table_key]
        new_array = generate_chinese_array(table_key, entries, size, font)
        pat = rf"const unsigned char Chinese_font_{size}\[\]\[\d+\] =[\s\S]*?\}};"
        if re.search(pat, text, re.S):
            text = re.sub(pat, new_array, text, count=1, flags=re.S)
            print(f"Updated Chinese_font_{size} ({len(entries)} glyphs)")
        else:
            # Insert new array before Chinese_font for next existing or after CHS tables
            anchor = "const unsigned char Chinese_font_11"
            if size == 8:
                anchor = "const unsigned char Chinese_font_11"
            elif size == 15:
                anchor = "const unsigned char Chinese_font_16"
            elif size == 28:
                anchor = None
            if anchor and anchor in text:
                text = text.replace(anchor, new_array + "\n\n" + anchor, 1)
                print(f"Inserted Chinese_font_{size}")
            elif size == 28:
                text = text.rstrip() + "\n\n" + new_array + "\n"
                print(f"Appended Chinese_font_{size}")

    with open(HEADER_OUT, "w", encoding="utf-8", newline="\n") as f:
        f.write(text)

    # English / ASCII fonts
    with open(ENG_HEADER_IN, "r", encoding="utf-8", errors="replace") as f:
        eng = f.read()

    ascii_targets = [
        (8, medium, None), (11, medium, None), (12, medium, None), (13, medium, "ascii_1306"),
        (15, medium, None), (16, medium, "ascii_1608"), (24, medium, "ascii_2412"),
        (28, semibold, None),
    ]
    for size, ttf, legacy_name in ascii_targets:
        font = ImageFont.truetype(ttf, size - 1)
        name, arr = generate_ascii_array(size, font, legacy_name)
        pat = rf"const unsigned char {name}\[\]\[\d+\][\s\S]*?\}};"
        if re.search(pat, eng, re.S):
            eng = re.sub(pat, arr, eng, count=1, flags=re.S)
            print(f"Updated {name}")
        else:
            auto_name, _ = generate_ascii_array(size, font)
            pat2 = rf"const unsigned char {auto_name}\[\]\[\d+\][\s\S]*?\}};"
            if auto_name != name and re.search(pat2, eng, re.S):
                eng = re.sub(pat2, arr, eng, count=1, flags=re.S)
                print(f"Updated {auto_name} -> {name}")
            else:
                eng = eng.rstrip() + "\n\n" + arr + "\n"
                print(f"Appended {name}")

    with open(ENG_HEADER_OUT, "w", encoding="utf-8", newline="\n") as f:
        f.write(eng)

    print("Done.")


if __name__ == "__main__":
    main()