#!/bin/bash
# ============================================================================
# PVPlex Edge Agent - Installer
# ============================================================================
# Installs the PVPlex Edge Agent on a Raspberry Pi.
# Usage: curl -sSL https://cloud.pvplex.com/download/install.sh | sudo bash
#
# Supported: Raspberry Pi 3B+, 4, 5 with Raspberry Pi OS Bookworm
# ============================================================================

set -euo pipefail

INSTALL_DIR="/opt/pvplex"
REPO_URL="https://github.com/pvplex-com/edge-agent.git"
CLOUD_URL="https://cloud.pvplex.com"
PACKAGE_URL="$CLOUD_URL/download/pvplex-edge.tar.gz"

RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m'

log()   { echo -e "${GREEN}[PVPlex]${NC} $1"; }
warn()  { echo -e "${YELLOW}[PVPlex]${NC} $1"; }
error() { echo -e "${RED}[PVPlex]${NC} $1"; exit 1; }

# -- Pre-checks --

if [ "$(id -u)" -ne 0 ]; then
    error "Bitte als root ausfuehren: sudo bash install.sh"
fi

ARCH=$(uname -m)
if [[ "$ARCH" != "aarch64" && "$ARCH" != "armv7l" && "$ARCH" != "armv6l" ]]; then
    error "Nicht unterstuetzt: $ARCH (nur Raspberry Pi armv7l/aarch64)"
fi

log "PVPlex Edge Agent Installer"
log "================================"
log "Plattform: $(uname -s) $ARCH"
log "Installationsverzeichnis: $INSTALL_DIR"
echo ""

# -- System packages --

log "Installiere Systempakete..."
apt-get update -qq
apt-get install -y -qq \
    python3 python3-pip python3-venv \
    git \
    curl \
    network-manager \
    dnsmasq \
    > /dev/null 2>&1

# Ensure NetworkManager manages WiFi
log "Konfiguriere NetworkManager..."
if [ -f /etc/NetworkManager/NetworkManager.conf ]; then
    if ! grep -q "managed=true" /etc/NetworkManager/NetworkManager.conf 2>/dev/null; then
        cat >> /etc/NetworkManager/NetworkManager.conf << 'NMEOF'

[device]
wifi.scan-rand-mac-address=no

[ifupdown]
managed=true
NMEOF
    fi
fi

# Disable default dnsmasq (we run our own instance for captive portal)
systemctl stop dnsmasq 2>/dev/null || true
systemctl disable dnsmasq 2>/dev/null || true

# Restart NetworkManager to pick up changes
systemctl restart NetworkManager
sleep 2

# -- Download & Install PVPlex --

if [ -d "$INSTALL_DIR/pvplex" ]; then
    log "Aktualisiere bestehende Installation..."
    # Backup config if exists
    if [ -f "$INSTALL_DIR/data/config.yaml" ]; then
        cp "$INSTALL_DIR/data/config.yaml" /tmp/pvplex-config-backup.yaml
    fi
fi

mkdir -p "$INSTALL_DIR"

# -- Install PVPlex (git clone for OTA updates) --

INSTALL_OK=false

if [ -d "$INSTALL_DIR/.git" ]; then
    # Existing git repo: pull latest
    log "Aktualisiere bestehende Installation..."
    cd "$INSTALL_DIR"
    git fetch origin 2>/dev/null || true
    # Checkout latest tag if available, otherwise pull master
    LATEST_TAG=$(git tag --sort=-v:refname 2>/dev/null | head -1)
    if [ -n "$LATEST_TAG" ]; then
        log "Neueste Version: $LATEST_TAG"
        git checkout "$LATEST_TAG" 2>/dev/null || git pull origin master
    else
        git pull origin master 2>/dev/null || true
    fi
    INSTALL_OK=true
else
    # Fresh install: try git clone first (needed for OTA updates)
    log "Installiere PVPlex Edge Agent..."

    if command -v git &>/dev/null; then
        log "Klone Git-Repository (fuer automatische Updates)..."
        if git clone --depth 1 "$REPO_URL" "$INSTALL_DIR" 2>/dev/null; then
            # Checkout latest tag if available
            cd "$INSTALL_DIR"
            git fetch --tags 2>/dev/null || true
            LATEST_TAG=$(git tag --sort=-v:refname 2>/dev/null | head -1)
            if [ -n "$LATEST_TAG" ]; then
                log "Wechsle zu Version $LATEST_TAG"
                git checkout "$LATEST_TAG" 2>/dev/null || true
            fi
            INSTALL_OK=true
        else
            warn "Git-Clone fehlgeschlagen, versuche Download..."
        fi
    fi
fi

# Fallback 1: Download tarball from cloud server
if [ "$INSTALL_OK" = false ]; then
    log "Lade Paket von $PACKAGE_URL herunter..."
    if curl -sSfL "$PACKAGE_URL" -o /tmp/pvplex-edge.tar.gz 2>/dev/null; then
        log "Download erfolgreich, entpacke..."
        tar -xzf /tmp/pvplex-edge.tar.gz -C "$INSTALL_DIR" --strip-components=0
        rm -f /tmp/pvplex-edge.tar.gz
        INSTALL_OK=true
        warn "Installation ohne Git - automatische Updates nicht verfuegbar."
        warn "Fuer Updates: git installieren und Installer erneut ausfuehren."
    fi
fi

# Fallback 2: Local files (USB stick)
if [ "$INSTALL_OK" = false ]; then
    SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
    if [ -f "$SCRIPT_DIR/requirements.txt" ] && [ -d "$SCRIPT_DIR/pvplex" ]; then
        log "Verwende lokale Dateien..."
        cp -r "$SCRIPT_DIR/pvplex" "$INSTALL_DIR/"
        cp -r "$SCRIPT_DIR/systemd" "$INSTALL_DIR/"
        cp "$SCRIPT_DIR/requirements.txt" "$INSTALL_DIR/"
        INSTALL_OK=true
        warn "Installation ohne Git - automatische Updates nicht verfuegbar."
    fi
fi

if [ "$INSTALL_OK" = false ]; then
    error "Installation fehlgeschlagen. Pruefe Internetverbindung oder nutze USB-Stick-Installation."
fi

# Restore config backup
if [ -f /tmp/pvplex-config-backup.yaml ]; then
    mkdir -p "$INSTALL_DIR/data"
    mv /tmp/pvplex-config-backup.yaml "$INSTALL_DIR/data/config.yaml"
fi

# -- Python venv --

log "Erstelle Python Virtual Environment..."
python3 -m venv "$INSTALL_DIR/venv"
"$INSTALL_DIR/venv/bin/pip" install --upgrade pip -q
"$INSTALL_DIR/venv/bin/pip" install -r "$INSTALL_DIR/requirements.txt" -q

# -- Create data directory --

mkdir -p "$INSTALL_DIR/data"

# Write initial state if not exists
if [ ! -f "$INSTALL_DIR/data/setup_state.json" ]; then
    echo '{"state": "unconfigured"}' > "$INSTALL_DIR/data/setup_state.json"
fi

# -- Install systemd services --

log "Installiere systemd Services..."
cp "$INSTALL_DIR/systemd/pvplex-boot.service" /etc/systemd/system/
cp "$INSTALL_DIR/systemd/pvplex-edge.service" /etc/systemd/system/
cp "$INSTALL_DIR/systemd/pvplex-setup.service" /etc/systemd/system/

systemctl daemon-reload

# Only enable the boot manager - it handles starting edge/setup
systemctl enable pvplex-boot.service
systemctl disable pvplex-edge.service 2>/dev/null || true
systemctl disable pvplex-setup.service 2>/dev/null || true

# -- Serial port permissions --

# Add current user to dialout group for serial access
if id "pi" &>/dev/null; then
    usermod -a -G dialout pi
fi

# -- Done --

echo ""
log "============================================"
log "  Installation abgeschlossen!"
log "============================================"
log ""
log "Naechste Schritte:"
log "  1. Starte den Raspberry Pi neu: sudo reboot"
log "  2. Verbinde dich mit dem WLAN 'PVPlex-XXXX'"
log "  3. Der Einrichtungsassistent oeffnet sich automatisch"
log "  4. Folge den 4 Schritten zur Konfiguration"
log ""
log "Bei Problemen:"
log "  sudo systemctl status pvplex-boot"
log "  sudo journalctl -u pvplex-boot -f"
log ""

read -p "Jetzt neustarten? [j/N] " -n 1 -r
echo ""
if [[ $REPLY =~ ^[Jj]$ ]]; then
    log "Neustart..."
    reboot
fi