#!/usr/bin/env bash
# Creates a Chromium webapp .desktop entry with favicon as icon.
# Usage: create-webapp.sh <url> [display-name]

set -euo pipefail

usage() {
    echo "Usage: $(basename "$0") <url> [display-name]"
    echo
    echo "  Fetches the page title and favicon, then writes a .desktop"
    echo "  entry that opens the URL in Chromium app-window mode (no tabs/address bar)."
    exit 1
}

[[ $# -lt 1 ]] && usage

URL="$1"
CUSTOM_NAME="${2:-}"

# Ensure scheme
[[ "$URL" != http://* && "$URL" != https://* ]] && URL="https://$URL"

BASE_URL=$(echo "$URL" | grep -oE 'https?://[^/]+')
DOMAIN=$(echo "$BASE_URL" | sed -E 's|https?://(www\.)?||')

echo "Fetching: $URL"
PAGE_HTML=$(curl -sL --max-time 15 \
    -A "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36" \
    "$URL" 2>/dev/null || echo "")

# Resolve app name from <title> or argument
if [[ -n "$CUSTOM_NAME" ]]; then
    APP_NAME="$CUSTOM_NAME"
else
    APP_NAME=$(echo "$PAGE_HTML" | python3 -c '
import sys, re, html as html_mod
content = sys.stdin.read()
m = re.search(r"<title[^>]*>([^<]+)</title>", content, re.IGNORECASE)
print(html_mod.unescape(m.group(1).strip()) if m else "", end="")
' 2>/dev/null || true)
    APP_NAME="${APP_NAME:-$DOMAIN}"
fi

# Safe identifier for filenames / WM_CLASS
SAFE_ID=$(echo "$APP_NAME" | tr '[:upper:]' '[:lower:]' | tr -cs 'a-z0-9' '-' | sed 's/^-*//;s/-*$//')
[[ -z "$SAFE_ID" ]] && SAFE_ID="$DOMAIN"

# Find best favicon from HTML link tags (largest declared size wins)
FAVICON_URL=$(echo "$PAGE_HTML" | python3 -c '
import sys, re
from urllib.parse import urljoin

base = sys.argv[1]
content = sys.stdin.read()

candidates = []
for link in re.findall(r"<link([^>]+?)/??>", content, re.IGNORECASE | re.DOTALL):
    rel_m = re.search(r"rel=[\"'"'"']([^\"'"'"']+)[\"'"'"']", link, re.IGNORECASE)
    if not rel_m or "icon" not in rel_m.group(1).lower():
        continue
    href_m = re.search(r"href=[\"'"'"']([^\"'"'"']+)[\"'"'"']", link, re.IGNORECASE)
    if not href_m:
        continue
    size = 0
    sizes_m = re.search(r"sizes=[\"'"'"']([^\"'"'"']+)[\"'"'"']", link, re.IGNORECASE)
    if sizes_m:
        val = sizes_m.group(1).lower().split("x")[0]
        try:
            size = 999 if val == "any" else int(val)
        except ValueError:
            pass
    candidates.append((size, href_m.group(1)))

if candidates:
    candidates.sort(key=lambda x: x[0], reverse=True)
    print(urljoin(base, candidates[0][1]), end="")
' "$BASE_URL" 2>/dev/null || true)

FAVICON_URL="${FAVICON_URL:-$BASE_URL/favicon.ico}"
echo "Favicon: $FAVICON_URL"

# Download icon
ICON_DIR="$HOME/.local/share/icons/webapps"
mkdir -p "$ICON_DIR"

TMP=$(mktemp /tmp/webapp-icon.XXXXXX)
trap 'rm -f "$TMP"' EXIT

ICON_PATH="chromium"  # fallback

if curl -sL --max-time 10 -A "Mozilla/5.0" -o "$TMP" "$FAVICON_URL" && [[ -s "$TMP" ]]; then
    if command -v convert &>/dev/null \
       && convert "${TMP}[0]" -resize 128x128\> "${ICON_DIR}/${SAFE_ID}.png" 2>/dev/null; then
        ICON_PATH="${ICON_DIR}/${SAFE_ID}.png"
        echo "Icon: $ICON_PATH  (PNG via ImageMagick)"
    else
        MIME=$(file -b --mime-type "$TMP")
        EXT="${MIME##*/}"
        [[ "$EXT" == "x-icon" || "$EXT" == "vnd.microsoft.icon" ]] && EXT="ico"
        cp "$TMP" "${ICON_DIR}/${SAFE_ID}.${EXT}"
        ICON_PATH="${ICON_DIR}/${SAFE_ID}.${EXT}"
        echo "Icon: $ICON_PATH  ($MIME)"
    fi
else
    echo "Warning: could not fetch favicon — using chromium default icon"
fi

# Write .desktop file
DESKTOP_DIR="$HOME/.local/share/applications"
mkdir -p "$DESKTOP_DIR"
DESKTOP_FILE="${DESKTOP_DIR}/webapp-${SAFE_ID}.desktop"

cat > "$DESKTOP_FILE" << DESKTOP
[Desktop Entry]
Version=1.0
Type=Application
Name=${APP_NAME}
Exec=chromium --app=${URL}
Icon=${ICON_PATH}
Terminal=false
Categories=Network;WebBrowser;
StartupWMClass=${SAFE_ID}
DESKTOP

chmod +x "$DESKTOP_FILE"

echo
echo "Created : $DESKTOP_FILE"
echo "  Name  : $APP_NAME"
echo "  URL   : $URL"
echo "  Icon  : $ICON_PATH"