#!/bin/sh
set -e

RELEASES_BASE="https://releases.dmagh.ai"
INSTALL_DIR="/usr/local/bin"
BINARY_NAME="dmagh-agent"

main() {
    echo ""
    echo "  ╔═══════════════════════════════════════════╗"
    echo "  ║   DMAGH Agent Installer                   ║"
    echo "  ╚═══════════════════════════════════════════╝"
    echo ""

    OS=$(uname -s | tr '[:upper:]' '[:lower:]')
    ARCH=$(uname -m)

    case "$ARCH" in
        x86_64|amd64)  ARCH="amd64" ;;
        aarch64|arm64) ARCH="arm64" ;;
        *)
            echo "  ✗ Unsupported architecture: $ARCH"
            exit 1
            ;;
    esac

    case "$OS" in
        linux)  OS="linux" ;;
        darwin) OS="darwin" ;;
        *)
            echo "  ✗ Unsupported OS: $OS"
            exit 1
            ;;
    esac

    echo "  Platform:  ${OS}/${ARCH}"

    # Check dependencies
    if ! command -v curl >/dev/null 2>&1 && ! command -v wget >/dev/null 2>&1; then
        echo "  ✗ curl or wget is required"
        exit 1
    fi

    # Get latest version
    echo "  Fetching latest version..."
    VERSION_JSON=$(download "${RELEASES_BASE}/dist/latest.json")
    VERSION=$(echo "$VERSION_JSON" | grep -o '"version"[[:space:]]*:[[:space:]]*"[^"]*"' | head -1 | cut -d'"' -f4)

    if [ -z "$VERSION" ]; then
        echo "  ✗ Could not determine latest version"
        exit 1
    fi

    echo "  Version:   v${VERSION}"

    # Check if already installed
    if command -v "$BINARY_NAME" >/dev/null 2>&1; then
        CURRENT=$("$BINARY_NAME" version 2>/dev/null | head -1 | awk '{print $2}' || echo "unknown")
        if [ "$CURRENT" = "$VERSION" ]; then
            echo "  ✓ Already up to date (v${VERSION})"
            exit 0
        fi
        echo "  Upgrading from ${CURRENT} → v${VERSION}"
    fi

    # Download binary
    DOWNLOAD_URL="${RELEASES_BASE}/dist/${BINARY_NAME}-${OS}-${ARCH}"
    TMP_FILE=$(mktemp)
    
    echo "  Downloading ${BINARY_NAME}-${OS}-${ARCH}..."
    download_file "$DOWNLOAD_URL" "$TMP_FILE"

    chmod +x "$TMP_FILE"

    # Verify it runs
    if ! "$TMP_FILE" version >/dev/null 2>&1; then
        echo "  ✗ Downloaded binary failed verification"
        rm -f "$TMP_FILE"
        exit 1
    fi

    # Install
    if [ -w "$INSTALL_DIR" ]; then
        mv "$TMP_FILE" "${INSTALL_DIR}/${BINARY_NAME}"
    else
        echo "  Installing to ${INSTALL_DIR} (requires sudo)..."
        sudo mv "$TMP_FILE" "${INSTALL_DIR}/${BINARY_NAME}"
    fi

    echo ""
    echo "  ✓ Installed ${BINARY_NAME} v${VERSION} to ${INSTALL_DIR}/${BINARY_NAME}"
    echo ""
    echo "  Get started:"
    echo "    ${BINARY_NAME} login        # Authenticate with DMAGH.AI"
    echo "    ${BINARY_NAME} connect      # Establish tunnel"
    echo "    ${BINARY_NAME} status       # Check status"
    echo "    ${BINARY_NAME} doctor       # Run diagnostics"
    echo ""
}

download() {
    url="$1"
    if command -v curl >/dev/null 2>&1; then
        curl -fsSL "$url"
    elif command -v wget >/dev/null 2>&1; then
        wget -qO- "$url"
    fi
}

download_file() {
    url="$1"
    dest="$2"
    if command -v curl >/dev/null 2>&1; then
        curl -fsSL -o "$dest" "$url"
    elif command -v wget >/dev/null 2>&1; then
        wget -q -O "$dest" "$url"
    fi
}

main "$@"