#!/bin/bash

NEXUS_ROOT="$HOME/nexus-core"
ROUTER_BACKUP="router:/tmp/mnt/Wingdrive2/nexus-backup/"

# ─── Helpers ──────────────────────────────────────────────────────────────────

is_wsl() {
    grep -qi microsoft /proc/version 2>/dev/null
}

detect_requirements() {
    if command -v nvidia-smi &>/dev/null && nvidia-smi &>/dev/null 2>&1; then
        echo "nvidia_requirements.txt"
    elif lspci 2>/dev/null | grep -qi nvidia; then
        echo "nvidia_requirements.txt"
    else
        echo "amd_requirements.txt"
    fi
}

get_windows_user() {
    powershell.exe -command '$env:USERNAME' 2>/dev/null | tr -d '\r\n'
}

setup_windows() {
    local win_user distro icon_src icon_win_dir icon_win_path wt_settings

    win_user=$(get_windows_user)
    distro="${WSL_DISTRO_NAME:-$(uname -n)}"

    if [ -z "$win_user" ] || [ ! -d "/mnt/c/Users/$win_user" ]; then
        echo "Could not locate Windows user directory — skipping Windows setup."
        return 1
    fi

    # Copy icon to Windows filesystem
    icon_src="$NEXUS_ROOT/assets/nexus-terminal.png"
    icon_win_dir="/mnt/c/Users/$win_user/AppData/Local/Nexus"
    mkdir -p "$icon_win_dir"
    cp "$icon_src" "$icon_win_dir/nexus-terminal.png"
    icon_win_path="C:\\Users\\$win_user\\AppData\\Local\\Nexus\\nexus-terminal.png"

    # Create combined init file so WT session has ncp, nvm, and Promethean prompt
    cat > "$HOME/.promethean_init" << 'EOF'
[[ -f ~/.bashrc ]] && source ~/.bashrc
[[ -f ~/.promethean_bashrc ]] && source ~/.promethean_bashrc
EOF

    # Patch Windows Terminal settings.json
    python3 - "$win_user" "$distro" "$icon_win_path" << 'PYEOF'
import json, uuid, sys
from pathlib import Path

win_user, distro, icon_path = sys.argv[1], sys.argv[2], sys.argv[3]

wt_candidates = [
    f"/mnt/c/Users/{win_user}/AppData/Local/Packages/Microsoft.WindowsTerminal_8wekyb3d8bbwe/LocalState/settings.json",
    f"/mnt/c/Users/{win_user}/AppData/Local/Packages/Microsoft.WindowsTerminalPreview_8wekyb3d8bbwe/LocalState/settings.json",
]

settings_path = next((Path(p) for p in wt_candidates if Path(p).exists()), None)

if not settings_path:
    print("Windows Terminal settings.json not found — skipping.")
    sys.exit(0)

with open(settings_path) as f:
    settings = json.load(f)

profiles = settings.setdefault("profiles", {}).setdefault("list", [])

if any(p.get("name") == "Promethean" for p in profiles):
    print("Promethean profile already exists — skipping.")
    sys.exit(0)

profiles.insert(0, {
    "guid": "{" + str(uuid.uuid4()) + "}",
    "name": "Promethean",
    "commandline": f"wsl.exe -d {distro} bash --init-file ~/.promethean_init",
    "startingDirectory": "~",
    "icon": icon_path,
})

with open(settings_path, "w") as f:
    json.dump(settings, f, indent=4)

print(f"Promethean profile added to Windows Terminal ({settings_path.parent.parent.name}).")
PYEOF

    # Create desktop shortcut
    powershell.exe -command "
\$ws = New-Object -ComObject WScript.Shell
\$s = \$ws.CreateShortcut(\"\$env:USERPROFILE\Desktop\Promethean.lnk\")
\$s.TargetPath = 'wt.exe'
\$s.Arguments = '--profile Promethean'
\$s.IconLocation = 'wt.exe,0'
\$s.Save()
" 2>/dev/null && echo "Desktop shortcut created." || echo "Could not create desktop shortcut — open Windows Terminal manually."
}

# ─── Step 1: Sync from router ─────────────────────────────────────────────────

echo "Pulling Nexus from router..."
mkdir -p "$NEXUS_ROOT"
rsync -avz --delete \
    --exclude='Promethean/' \
    --exclude='models/blobs/' \
    --exclude='ollama/' \
    --exclude='interface/web/node_modules/' \
    --exclude='interface/web/dist/' \
    --exclude='runtime/' \
    --exclude='__pycache__/' \
    --exclude='*.pyc' \
    -e ssh \
    "$ROUTER_BACKUP" "$NEXUS_ROOT/"

# ─── Step 2: Python venv ──────────────────────────────────────────────────────

echo ""
echo "Creating Python environment..."
python3 -m venv "$NEXUS_ROOT/Promethean"

# ─── Step 3: pip install ──────────────────────────────────────────────────────

echo ""
echo "Installing Python dependencies..."
req=$(detect_requirements)
echo "Detected: $req"
if [ -f "$NEXUS_ROOT/$req" ]; then
    "$NEXUS_ROOT/Promethean/bin/pip" install --upgrade pip -q
    "$NEXUS_ROOT/Promethean/bin/pip" install -r "$NEXUS_ROOT/$req"
else
    echo "Warning: $req not found — skipping pip install."
fi

# ─── Step 4: npm install ──────────────────────────────────────────────────────

echo ""
echo "Installing frontend dependencies..."
export NVM_DIR="$HOME/.nvm"
[ -s "$NVM_DIR/nvm.sh" ] && \. "$NVM_DIR/nvm.sh"
if command -v npm &>/dev/null; then
    cd "$NEXUS_ROOT/interface/web" && npm install
else
    echo "npm not found — install nvm/node then run 'cd $NEXUS_ROOT/interface/web && npm install'."
fi

# ─── Step 5: Register ncp in ~/.bashrc ───────────────────────────────────────

echo ""
echo "Registering ncp..."
if ! grep -q "nexus-core/management/nexus-cli.sh" "$HOME/.bashrc"; then
    cat >> "$HOME/.bashrc" << 'EOF'

# Nexus
ncp() {
    ~/nexus-core/management/nexus-cli.sh "$@"
}
alias promethean='source ~/.promethean_bashrc'
EOF
    echo "ncp registered in ~/.bashrc."
else
    echo "ncp already in ~/.bashrc — skipping."
fi

# ─── Step 6: Windows Terminal + desktop shortcut ──────────────────────────────

if is_wsl; then
    echo ""
    echo "Configuring Windows environment..."
    setup_windows || true
    echo ""
    echo "Reload your shell or open a new terminal for ncp to take effect."
fi

# ─── Done ─────────────────────────────────────────────────────────────────────

echo ""
echo "Installation complete. Nexus is ready."
if is_wsl; then
    echo "Open Windows Terminal → Promethean profile, or use the desktop shortcut."
else
    echo "Run 'ncp start' to launch Nexus."
fi