Import("env")  # noqa: F821

from pathlib import Path
import hashlib
import shutil
import subprocess


project_dir = Path(env.subst("$PROJECT_DIR"))  # noqa: F821
ui_dir = project_dir / "ui"
generated_dir = project_dir / "src" / "generated"
generated_dir.mkdir(parents=True, exist_ok=True)

npm = shutil.which("npm")
if npm and (ui_dir / "node_modules").is_dir():
    subprocess.run([npm, "run", "build"], cwd=ui_dir, check=True)

assets = {
    "indexHtml": ui_dir / "dist" / "index.html",
    "appCss": ui_dir / "dist" / "styles.min.css",
    "appJs": ui_dir / "dist" / "app.min.js",
}
if not all(path.is_file() for path in assets.values()):
    assets = {
        "indexHtml": ui_dir / "index.html",
        "appCss": ui_dir / "styles.css",
        "appJs": ui_dir / "app.js",
    }

missing = [str(path) for path in assets.values() if not path.is_file()]
if missing:
    raise SystemExit(
        "Missing UI assets: " + ", ".join(missing)
    )


def emit_array(name, data):
    lines = [f"const char {name}[] PROGMEM = {{"]
    for offset in range(0, len(data), 16):
        chunk = data[offset : offset + 16]
        values = ", ".join(f"0x{value:02X}" for value in chunk)
        lines.append(f"  {values},")
    lines.append("  0x00")
    lines.append("};")
    return "\n".join(lines)


def emit_length(name, data):
    return f"const std::size_t {name}Length = {len(data)}U;"


header_lines = [
    "#pragma once",
    "",
    "#include <Arduino.h>",
    "#include <pgmspace.h>",
    "",
    "#include <cstddef>",
    "",
]
source_lines = [
    "// Generated by scripts/embed_ui.py. Do not edit manually.",
    "#include \"UiAssets.h\"",
    "",
    "#include <cstddef>",
    "",
]

for name, path in assets.items():
    data = path.read_bytes()
    digest = hashlib.sha256(data).hexdigest()
    header_lines.append(f"extern const char {name}[] PROGMEM;")
    header_lines.append(f"extern const std::size_t {name}Length;")
    header_lines.append(f"extern const char {name}Sha256[] PROGMEM;")
    source_lines.extend(
        [
            emit_array(name, data),
            emit_length(name, data),
            f'const char {name}Sha256[] PROGMEM = "{digest}";',
            "",
        ]
    )

def write_if_changed(path, content):
    if path.is_file() and path.read_text(encoding="utf-8") == content:
        return
    path.write_text(content, encoding="utf-8")


write_if_changed(generated_dir / "UiAssets.h", "\n".join(header_lines) + "\n")
write_if_changed(generated_dir / "UiAssets.cpp", "\n".join(source_lines) + "\n")

print("Embedded UI assets:")
for name, path in assets.items():
    data = path.read_bytes()
    print(f"  {name}: {path.name} ({len(data)} bytes)")