#!/usr/bin/env bash
# Flow Pro Installation Script
# Downloads and installs Flow Pro CLI and Desktop application
# Requires valid Polar.sh license key
#
# Usage:
#   curl -fsSL https://install.flowexec.io | bash -s -- YOUR_LICENSE_KEY [VERSION]
#   FLOW_PRO_LICENSE=YOUR_LICENSE_KEY curl -fsSL https://install.flowexec.io | bash
#
# Environment Variables:
#   FLOW_PRO_LICENSE - License key (alternative to passing as argument)
#   FLOW_PRO_VERSION - Version to install (defaults to 'latest')
#   FLOW_PRO_DEBUG - Set to '1' for verbose output
#   FLOW_PRO_INSTALL_DIR - Installation directory (defaults to ~/.flow-pro)
#   FLOW_PRO_SKIP_DESKTOP - Set to '1' to skip desktop app installation

set -euo pipefail

# ============================================================================
# Configuration
# ============================================================================

INSTALL_DIR="${FLOW_PRO_INSTALL_DIR:-$HOME/.flow-pro}"
BIN_DIR="${INSTALL_DIR}/bin"
DOWNLOAD_DIR="${INSTALL_DIR}/downloads"
BASE_URL="${FLOW_PRO_BASE_URL:-https://releases.flowexec.io}"

# Parse command-line arguments
LICENSE_KEY="${1:-${FLOW_PRO_LICENSE:-}}"
VERSION="${2:-${FLOW_PRO_VERSION:-latest}}"
DEBUG="${FLOW_PRO_DEBUG:-0}"
SKIP_DESKTOP="${FLOW_PRO_SKIP_DESKTOP:-0}"

# ============================================================================
# Colors and Logging
# ============================================================================

# Color codes (disabled if not a TTY or NO_COLOR is set)
if [ -t 1 ] && [ -z "${NO_COLOR:-}" ]; then
    RED='\033[0;31m'
    GREEN='\033[0;32m'
    YELLOW='\033[1;33m'
    BLUE='\033[0;34m'
    MAGENTA='\033[0;35m'
    CYAN='\033[0;36m'
    BOLD='\033[1m'
    NC='\033[0m'
else
    RED=''
    GREEN=''
    YELLOW=''
    BLUE=''
    MAGENTA=''
    CYAN=''
    BOLD=''
    NC=''
fi

log_info() {
    echo -e "${BLUE}ℹ${NC} $1"
}

log_success() {
    echo -e "${GREEN}✓${NC} $1"
}

log_error() {
    echo -e "${RED}✗${NC} $1" >&2
}

log_warn() {
    echo -e "${YELLOW}⚠${NC} $1"
}

log_debug() {
    if [ "$DEBUG" = "1" ]; then
        echo -e "${CYAN}[DEBUG]${NC} $1"
    fi
}

log_step() {
    echo -e "\n${BOLD}${MAGENTA}▶${NC} ${BOLD}$1${NC}"
}

banner() {
    cat << "EOF"

   ,d8888b d8b
   88P'    88P
d888888P  d88
  ?88'    888   d8888b  ?88   d8P  d8P
  88P     ?88  d8P' ?88 d88  d8P' d8P'
 d88       88b 88b  d88 ?8b ,88b ,88'
d88'        88b`?8888P' `?888P'888P'

EOF
}

# ============================================================================
# Utility Functions
# ============================================================================

# Cleanup on error or exit
cleanup() {
    local exit_code=$?
    if [ $exit_code -ne 0 ]; then
        log_error "Installation failed!"
        if [ "$DEBUG" = "0" ]; then
            log_info "Run with FLOW_PRO_DEBUG=1 for more details"
        fi
    fi
    # Clean up temporary downloads on error
    if [ -d "$DOWNLOAD_DIR" ] && [ $exit_code -ne 0 ]; then
        log_debug "Cleaning up download directory: $DOWNLOAD_DIR"
        rm -rf "$DOWNLOAD_DIR"
    fi
}

trap cleanup EXIT

# Check if command exists
command_exists() {
    command -v "$1" &> /dev/null
}

# Download file with progress
download_file() {
    local url="$1"
    local output="$2"

    log_debug "Downloading: $url -> $output"

    if command_exists curl; then
        curl -fsSL --retry 3 --retry-delay 2 "$url" -o "$output"
    elif command_exists wget; then
        wget -q --retry-connrefused --waitretry=2 --tries=3 "$url" -O "$output"
    else
        log_error "Neither curl nor wget found. Please install curl or wget."
        exit 1
    fi
}

# Verify SHA256 checksum
verify_checksum() {
    local file="$1"
    local expected="$2"

    log_debug "Verifying checksum for: $file"
    log_debug "Expected: $expected"

    local actual=""
    if command_exists sha256sum; then
        actual=$(sha256sum "$file" | awk '{print $1}')
    elif command_exists shasum; then
        actual=$(shasum -a 256 "$file" | awk '{print $1}')
    else
        log_error "Neither sha256sum nor shasum found"
        exit 1
    fi

    log_debug "Actual: $actual"

    if [ "$actual" != "$expected" ]; then
        log_error "Checksum verification failed for $file"
        log_error "Expected: $expected"
        log_error "Got: $actual"
        return 1
    fi

    log_success "Checksum verified for $(basename "$file")"
    return 0
}

# ============================================================================
# Platform Detection
# ============================================================================

detect_platform() {
    local os=""
    local arch=""

    # Detect OS
    case "$(uname -s | tr '[:upper:]' '[:lower:]')" in
        linux*)
            os="linux"
            ;;
        darwin*)
            os="darwin"
            ;;
        *)
            log_error "Unsupported operating system: $(uname -s)"
            log_error "Flow Pro supports: Linux, macOS"
            exit 1
            ;;
    esac

    # Detect architecture
    case "$(uname -m)" in
        x86_64|amd64)
            arch="amd64"
            ;;
        arm64|aarch64)
            arch="arm64"
            ;;
        *)
            log_error "Unsupported architecture: $(uname -m)"
            log_error "Flow Pro supports: x86_64 (amd64), arm64"
            exit 1
            ;;
    esac

    echo "${os}-${arch}"
}

# ============================================================================
# License Validation
# ============================================================================

validate_license() {
    local license="$1"

    log_step "Validating license with Polar.sh..."

    if [ -z "$license" ]; then
        log_error "No license key provided!"
        echo ""
        echo "Usage:"
        echo "  curl -fsSL https://install.flowexec.io | bash -s -- YOUR_LICENSE_KEY"
        echo ""
        echo "Or set environment variable:"
        echo "  export FLOW_PRO_LICENSE=YOUR_LICENSE_KEY"
        echo "  curl -fsSL https://install.flowexec.io | bash"
        echo ""
        echo "Get your license at: ${BOLD}https://flowexec.io/pro${NC}"
        exit 1
    fi

    log_debug "License key: ${license:0:10}..."
    flow license set "$license"
}

# ============================================================================
# Version Resolution
# ============================================================================

resolve_version() {
    local version="$1"

    if [ "$version" = "latest" ]; then
        log_step "Resolving latest version..."

        # Download latest version manifest
        local version_json="${DOWNLOAD_DIR}/version.json"
        download_file "${BASE_URL}/latest/version.json" "$version_json"

        if command_exists jq; then
            version=$(jq -r '.version' "$version_json")
            log_success "Latest version: $version"
        else
            log_error "jq is required to resolve latest version"
            log_info "Please install jq or specify a version explicitly"
            exit 1
        fi
    fi

    echo "$version"
}

# ============================================================================
# Installation
# ============================================================================

install_cli() {
    local version="$1"
    local platform="$2"

    log_step "Installing Flow Pro CLI..."

    local version_json="${DOWNLOAD_DIR}/version.json"
    local version_url="${BASE_URL}/${version}/version.json"

    log_info "Downloading version manifest..."
    download_file "$version_url" "$version_json"

    if ! command_exists jq; then
        log_error "jq is required for installation"
        log_info "Install jq: https://stedolan.github.io/jq/download/"
        exit 1
    fi

    local cli_info=$(jq -r ".cli[\"$platform\"]" "$version_json")
    if [ "$cli_info" = "null" ] || [ -z "$cli_info" ]; then
        log_error "No CLI binary found for platform: $platform"
        log_info "Available platforms:"
        jq -r '.cli | keys[]' "$version_json"
        exit 1
    fi

    local filename=$(echo "$cli_info" | jq -r '.filename')
    local checksum=$(echo "$cli_info" | jq -r '.checksum')

    log_info "Downloading CLI: $filename"
    local archive_path="${DOWNLOAD_DIR}/${filename}"
    download_file "${BASE_URL}/${version}/${filename}" "$archive_path"

    verify_checksum "$archive_path" "$checksum"

    log_info "Extracting CLI binary..."
    mkdir -p "$BIN_DIR"
    tar -xzf "$archive_path" -C "$DOWNLOAD_DIR"

    local binary=$(find "$DOWNLOAD_DIR" -name "flow" -type f | head -1)
    if [ -z "$binary" ]; then
        log_error "Binary 'flow' not found in archive"
        exit 1
    fi

    mv "$binary" "${BIN_DIR}/flow"
    chmod +x "${BIN_DIR}/flow"

    if "${BIN_DIR}/flow" --version &> /dev/null; then
        local installed_version=$("${BIN_DIR}/flow" --version | head -1)
        log_success "CLI installed: $installed_version"
    else
        log_error "CLI installation verification failed"
        exit 1
    fi
}

install_desktop_macos() {
    local version="$1"
    local version_json="${DOWNLOAD_DIR}/version.json"

    log_step "Installing Flow Pro Desktop (macOS)..."

    local desktop_info=$(jq -r '.desktop.darwin' "$version_json")
    if [ "$desktop_info" = "null" ] || [ -z "$desktop_info" ]; then
        log_warn "No macOS desktop app found for this version"
        return 0
    fi

    local filename=$(echo "$desktop_info" | jq -r '.filename')
    local checksum=$(echo "$desktop_info" | jq -r '.checksum')

    log_info "Downloading Desktop: $filename"
    local dmg_path="${DOWNLOAD_DIR}/${filename}"
    download_file "${BASE_URL}/${version}/${filename}" "$dmg_path"

    verify_checksum "$dmg_path" "$checksum"

    log_info "Mounting DMG..."
    local mount_point=$(hdiutil attach "$dmg_path" | grep Volumes | awk '{print $3}')

    if [ -z "$mount_point" ]; then
        log_error "Failed to mount DMG"
        return 1
    fi

    log_debug "Mounted at: $mount_point"

    local app_bundle=$(find "$mount_point" -name "*.app" -maxdepth 1 | head -1)

    if [ -z "$app_bundle" ]; then
        hdiutil detach "$mount_point" -quiet
        log_error "No .app bundle found in DMG"
        return 1
    fi

    log_info "Installing to /Applications..."
    sudo cp -R "$app_bundle" /Applications/

    hdiutil detach "$mount_point" -quiet

    log_success "Desktop app installed to /Applications"
}

install_desktop_linux() {
    local version="$1"
    local version_json="${DOWNLOAD_DIR}/version.json"

    log_step "Installing Flow Pro Desktop (Linux)..."

    local desktop_info=$(jq -r '.desktop.linux' "$version_json")
    if [ "$desktop_info" = "null" ] || [ -z "$desktop_info" ]; then
        log_warn "No Linux desktop app found for this version"
        return 0
    fi

    local filename=$(echo "$desktop_info" | jq -r '.filename')
    local checksum=$(echo "$desktop_info" | jq -r '.checksum')

    log_info "Downloading Desktop: $filename"
    local appimage_path="${DOWNLOAD_DIR}/${filename}"
    download_file "${BASE_URL}/${version}/${filename}" "$appimage_path"

    verify_checksum "$appimage_path" "$checksum"

    mv "$appimage_path" "${BIN_DIR}/flow-desktop"
    chmod +x "${BIN_DIR}/flow-desktop"

    log_info "Creating desktop entry..."
    local desktop_file="${HOME}/.local/share/applications/flow-pro.desktop"
    mkdir -p "$(dirname "$desktop_file")"

    cat > "$desktop_file" << EOF
[Desktop Entry]
Type=Application
Name=Flow Desktop
Comment=Flow Automation Platform
Exec=${BIN_DIR}/flow-desktop
Icon=flow-pro
Terminal=false
Categories=Development;Utility;
EOF

    log_success "Desktop app installed"
    log_info "Run with: flow-desktop"
}

# ============================================================================
# PATH Configuration
# ============================================================================

configure_path() {
    log_step "Configuring PATH..."

    if echo "$PATH" | grep -q "${BIN_DIR}"; then
        log_success "Already in PATH"
        return 0
    fi

    local shell_configs=(
        "$HOME/.bashrc"
        "$HOME/.zshrc"
        "$HOME/.profile"
    )

    local path_line="export PATH=\"${BIN_DIR}:\$PATH\""
    local added=false

    for config in "${shell_configs[@]}"; do
        if [ -f "$config" ]; then
            if ! grep -q "flow-pro/bin" "$config"; then
                echo "" >> "$config"
                echo "# Flow Pro" >> "$config"
                echo "$path_line" >> "$config"
                log_success "Added to $(basename "$config")"
                added=true
            fi
        fi
    done

    if [ "$added" = true ]; then
        log_warn "Restart your shell or run: source ~/.bashrc (or ~/.zshrc)"
    else
        log_info "Add to PATH manually: $path_line"
    fi
}

# ============================================================================
# Version Tracking
# ============================================================================

save_installation_info() {
    local version="$1"
    local platform="$2"

    log_step "Saving installation info..."

    local info_file="${INSTALL_DIR}/version.json"
    local installed=$(date -u +"%Y-%m-%dT%H:%M:%SZ")

    cat > "$info_file" << EOF
{
  "version": "$version",
  "platform": "$platform",
  "installed": "$installed",
  "install_dir": "$INSTALL_DIR",
  "bin_dir": "$BIN_DIR"
}
EOF

    log_debug "Installation info saved to $info_file"
}

# ============================================================================
# Main Installation Flow
# ============================================================================

main() {
    clear
    banner
    echo ""

    log_info "Flow Pro Installer"
    log_info "Installation directory: $INSTALL_DIR"
    echo ""

    PLATFORM=$(detect_platform)
    log_info "Platform: $PLATFORM"

    OS=$(echo "$PLATFORM" | cut -d'-' -f1)

    VERSION=$(resolve_version "$VERSION")
    log_info "Installing version: $VERSION"

    mkdir -p "$INSTALL_DIR" "$BIN_DIR" "$DOWNLOAD_DIR"

    install_cli "$VERSION" "$PLATFORM"

    validate_license "$LICENSE_KEY"

    if [ "$SKIP_DESKTOP" = "0" ]; then
        case "$OS" in
            darwin)
                install_desktop_macos "$VERSION" || log_warn "Desktop installation failed (non-fatal)"
                ;;
            linux)
                install_desktop_linux "$VERSION" || log_warn "Desktop installation failed (non-fatal)"
                ;;
        esac
    else
        log_info "Skipping desktop app installation (FLOW_PRO_SKIP_DESKTOP=1)"
    fi

    configure_path

    save_installation_info "$VERSION" "$PLATFORM"

    log_debug "Cleaning up downloads..."
    rm -rf "$DOWNLOAD_DIR"

    echo ""
    echo -e "${GREEN}${BOLD}"
    echo "╔════════════════════════════════════════════════════════╗"
    echo "║                                                        ║"
    echo "║   Flow Pro installed successfully!                     ║"
    echo "║                                                        ║"
    echo "╚════════════════════════════════════════════════════════╝"
    echo -e "${NC}"
    echo ""
    log_info "${BOLD}Version:${NC} $VERSION"
    log_info "${BOLD}Location:${NC} $BIN_DIR/flow"
    echo ""
    log_info "${BOLD}Next steps:${NC}"
    echo "  1. Restart your shell or run: ${BOLD}source ~/.bashrc${NC}"
    echo "  2. Verify installation: ${BOLD}flow --version${NC}"
    echo "  3. Get started: ${BOLD}flow --help${NC}"
    echo ""
    log_info "Documentation: ${BOLD}https://flowexec.io/${NC}"
    echo ""
}

# Run main installation
main