#!/usr/bin/env bash
#
# qvm-reset - Wipe VM overlay and workspace registry
#
# This script resets the VM to a clean state by deleting the overlay.qcow2
# and workspaces.json files. This is useful when you want to start fresh
# or if the VM state has become corrupted.
#
# IMPORTANT: This does NOT delete the base image (base.qcow2), so you won't
# need to re-download or rebuild the NixOS image.
#
# Usage: qvm reset [-f|--force]
#        -f, --force    Skip confirmation prompt
#

set -euo pipefail

# Source common library
readonly QVM_LIB_DIR="${QVM_LIB_DIR:-$(cd "$(dirname "${BASH_SOURCE[0]}")/../lib" && pwd)}"
source "${QVM_LIB_DIR}/common.sh"

# Get path to qvm-stop script
readonly QVM_BIN_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
readonly QVM_STOP="${QVM_BIN_DIR}/qvm-stop"

#
# confirm_reset - Prompt user for confirmation
# Returns: 0 if user confirms, exits script if user cancels
#
confirm_reset() {
    echo
    log_warn "This will delete:"
    
    if [[ -f "$QVM_OVERLAY" ]]; then
        echo "  - $QVM_OVERLAY"
    fi
    
    if [[ -f "$QVM_WORKSPACES_FILE" ]]; then
        echo "  - $QVM_WORKSPACES_FILE"
    fi
    
    if [[ ! -f "$QVM_OVERLAY" ]] && [[ ! -f "$QVM_WORKSPACES_FILE" ]]; then
        log_info "No files to delete (already clean)"
        exit 0
    fi
    
    echo
    echo "The base image (base.qcow2) and cache directories will NOT be deleted."
    echo
    read -p "Continue with reset? [y/N] " -n 1 -r
    echo
    
    if [[ ! $REPLY =~ ^[Yy]$ ]]; then
        log_info "Reset cancelled"
        exit 0
    fi
}

#
# main - Main reset orchestration
#
main() {
    local force=false
    
    # Parse arguments
    while [[ $# -gt 0 ]]; do
        case "$1" in
            -f|--force)
                force=true
                shift
                ;;
            *)
                die "Unknown option: $1"
                ;;
        esac
    done
    
    # Confirm unless --force is used
    if [[ "$force" != true ]]; then
        confirm_reset
    fi
    
    # Stop VM if running
    if is_vm_running; then
        log_info "VM is running, stopping it first..."
        "$QVM_STOP"
    fi
    
    # Delete overlay if it exists
    if [[ -f "$QVM_OVERLAY" ]]; then
        log_info "Deleting overlay: $QVM_OVERLAY"
        rm -f "$QVM_OVERLAY"
    else
        log_info "Overlay does not exist (nothing to delete)"
    fi
    
    # Delete workspaces registry if it exists
    if [[ -f "$QVM_WORKSPACES_FILE" ]]; then
        log_info "Deleting workspaces registry: $QVM_WORKSPACES_FILE"
        rm -f "$QVM_WORKSPACES_FILE"
    else
        log_info "Workspaces registry does not exist (nothing to delete)"
    fi
    
    # Print success message with next steps
    echo
    log_info "Reset complete!"
    echo
    echo "Next steps:"
    echo "  - Run 'qvm start' to boot the VM with a fresh overlay"
    echo "  - Your base image (base.qcow2) is still intact"
    echo "  - Cache directories (cargo-home, pnpm-store, etc.) are preserved"
    echo
}

main "$@"