#!/bin/bash
# Parahub Mesh Firmware Builder
# Uses OpenWrt Image Builder to create custom firmware with mesh packages.
#
# Usage: ./scripts/build.sh <device>
# Example: ./scripts/build.sh axt1800

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
PROJECT_DIR="$(dirname "$SCRIPT_DIR")"

OPENWRT_VERSION="${OPENWRT_VERSION:-25.12.0-rc4}"

# ============================================================================
# Device Database (device → target/subtarget + Image Builder profile)
# ============================================================================

device_config() {
    local device="$1"
    case "$device" in
        axt1800)
            OPENWRT_TARGET="qualcommax/ipq60xx"
            PROFILE="glinet_gl-axt1800"
            ;;
        mt3000)
            OPENWRT_TARGET="mediatek/filogic"
            PROFILE="glinet_gl-mt3000"
            ;;
        mt6000)
            OPENWRT_TARGET="mediatek/filogic"
            PROFILE="glinet_gl-mt6000"
            ;;
        ax6s)
            OPENWRT_TARGET="mediatek/filogic"
            PROFILE="xiaomi_redmi-router-ax6s"
            ;;
        ax53u)
            OPENWRT_TARGET="ramips/mt7621"
            PROFILE="asus_rt-ax53u"
            ;;
        *)
            return 1
            ;;
    esac
}

# ============================================================================
# Packages
# ============================================================================

PACKAGES_CORE=(
    # batman-adv mesh
    kmod-batman-adv
    batctl-full

    # 802.11s mesh support (replace basic wpad, includes OWE)
    wpad-mesh-mbedtls
    -wpad-basic-mbedtls

    # Yggdrasil overlay network
    yggdrasil

    # GRE6 tunnel (guest traffic → VPS gateway)
    kmod-gre6

    # WireGuard (optional local Mullvad via parahub-mullvad script)
    kmod-wireguard
    wireguard-tools
    luci-proto-wireguard

    # DNS-over-HTTPS for guest privacy
    https-dns-proxy

    # SQM traffic shaping
    sqm-scripts
    kmod-sched-cake

    # Management
    luci
    luci-app-sqm
)

PACKAGES_FULL=(
    "${PACKAGES_CORE[@]}"

    # Diagnostics
    tcpdump
    iperf3
    iwinfo
    curl
)

# ============================================================================
# Functions
# ============================================================================

usage() {
    echo "Usage: $0 <device>"
    echo ""
    echo "Devices:"
    echo "  axt1800   GL.iNet GL-AXT1800 (Slate AX)    qualcommax/ipq60xx"
    echo "  mt3000    GL.iNet GL-MT3000 (Beryl AX)      mediatek/filogic"
    echo "  mt6000    GL.iNet GL-MT6000 (Flint 2)       mediatek/filogic"
    echo "  ax6s      Xiaomi Redmi AX6S                 mediatek/filogic"
    echo "  ax53u     Asus RT-AX53U                    ramips/mt7621"
    echo ""
    echo "OpenWrt version: ${OPENWRT_VERSION} (override with OPENWRT_VERSION env var)"
    echo ""
    echo "Environment variables:"
    echo "  OPENWRT_VERSION  OpenWrt release (default: ${OPENWRT_VERSION})"
    echo "  PACKAGES_EXTRA   Additional packages (space-separated)"
    exit 1
}

builder_dir() {
    echo "${PROJECT_DIR}/imagebuilder-${OPENWRT_VERSION}-${OPENWRT_TARGET//\//-}"
}

download_builder() {
    local dir
    dir="$(builder_dir)"

    if [ -d "$dir" ]; then
        echo "Image Builder already downloaded at ${dir##*/}, skipping..."
        return
    fi

    # OpenWrt 25.x uses .tar.zst, older uses .tar.xz
    local base_url="https://downloads.openwrt.org/releases/${OPENWRT_VERSION}/targets/${OPENWRT_TARGET}/openwrt-imagebuilder-${OPENWRT_VERSION}-${OPENWRT_TARGET//\//-}.Linux-x86_64"
    echo "Downloading OpenWrt Image Builder ${OPENWRT_VERSION} for ${OPENWRT_TARGET}..."
    mkdir -p "$dir"

    if wget -q --spider "${base_url}.tar.zst" 2>/dev/null; then
        wget -q --show-progress -O- "${base_url}.tar.zst" | zstd -d | tar -x --strip-components=1 -C "$dir"
    else
        wget -q --show-progress -O- "${base_url}.tar.xz" | tar -xJ --strip-components=1 -C "$dir"
    fi
}

build_firmware() {
    local dir
    dir="$(builder_dir)"
    local packages="${PACKAGES_FULL[*]} ${PACKAGES_EXTRA:-}"

    echo "Building firmware for profile: ${PROFILE}"
    echo "Packages: ${packages}"
    echo "Custom files: ${PROJECT_DIR}/files"

    make -C "$dir" image \
        PROFILE="$PROFILE" \
        PACKAGES="$packages" \
        FILES="${PROJECT_DIR}/files" \
        BIN_DIR="${PROJECT_DIR}/output"

    echo ""
    echo "Build complete! Firmware images:"
    ls -lh "${PROJECT_DIR}/output/"*.bin 2>/dev/null || true
    ls -lh "${PROJECT_DIR}/output/"*.img* 2>/dev/null || true
    ls -lh "${PROJECT_DIR}/output/"*.itb 2>/dev/null || true
}

# ============================================================================
# Main
# ============================================================================

if [ $# -lt 1 ]; then
    usage
fi

INPUT="$1"

if ! device_config "$INPUT"; then
    echo "Error: Unknown device '${INPUT}'"
    echo ""
    usage
fi

echo "=== Parahub Mesh Firmware Builder ==="
echo "Device:  ${INPUT}"
echo "OpenWrt: ${OPENWRT_VERSION}"
echo "Target:  ${OPENWRT_TARGET}"
echo "Profile: ${PROFILE}"
echo ""

download_builder
build_firmware