#!/bin/bash

# Script to list available snapshots from Restic repository
# Usage: ./list-snapshots [service_name]

set -e

# Configuration should be sourced before running: source backup.env

# Configuration
BACKUP_DIR="$BACKUP_BASE_DIR"
CONFIG_FILE="$RESTIC_CONFIG_FILE"

# Colors for output
BLUE='\033[0;34m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

show_help() {
    echo "Usage: $0 [service_name]"
    echo ""
    echo "List available snapshots from Restic repository"
    echo ""
    echo "Examples:"
    echo "  $0              # List all snapshots grouped by service"
    echo "  $0 paperless    # List snapshots for paperless service only"
    echo ""
}

log() {
    echo -e "${BLUE}[INFO]${NC} $1"
}

list_all_snapshots() {
    log "All available snapshots:"
    echo ""
    
    local snapshots=$(restic snapshots --json 2>/dev/null)
    
    if [ -z "$snapshots" ] || [ "$snapshots" = "null" ] || [ "$snapshots" = "[]" ]; then
        echo "No snapshots found in repository."
        return
    fi
    
    # Filter out timestamp tags (like paperless-20250609-115655) and retention tags
    local services=$(echo "$snapshots" | jq -r '.[].tags[]' | grep -v -E '^(daily|weekly|monthly|yearly)$' | grep -v -E '^.*-[0-9]{8}-[0-9]{6}$' | sort -u)
    
    for service in $services; do
        echo -e "${GREEN}=== $service ===${NC}"
        
        # Display snapshots for this service
        echo "$snapshots" | jq -r ".[] | select(.tags[] == \"$service\") | \"\(.short_id)  \(.time[:19])  \(.summary.total_files_processed)  \((.summary.total_bytes_processed / 1024 / 1024 / 1024 * 100 | floor) / 100)\"" | \
        awk 'BEGIN {printf "%-10s %-20s %-10s %s\n", "ID", "DATE", "FILES", "SIZE(GB)"; print "-------------------------------------------------------"} {printf "%-10s %-20s %-10s %.2f\n", $1, $2, $3, $4}'
        
        echo ""
    done
}

list_service_snapshots() {
    local service="$1"
    
    log "Snapshots for service: $service"
    echo ""
    
    local snapshots=$(restic snapshots --tag "$service" --json 2>/dev/null)
    
    if [ -z "$snapshots" ] || [ "$snapshots" = "null" ] || [ "$snapshots" = "[]" ]; then
        echo "No snapshots found for service: $service"
        return
    fi
    
    # Display snapshots in a readable format
    echo "$snapshots" | jq -r '.[] | "\(.short_id)  \(.time[:19])  \(.tags | join(","))  \(.summary.total_files_processed)  \((.summary.total_bytes_processed / 1024 / 1024 / 1024 * 100 | floor) / 100)"' | \
    awk 'BEGIN {printf "%-10s %-20s %-35s %-10s %s\n", "ID", "DATE", "TAGS", "FILES", "SIZE(GB)"; print "-------------------------------------------------------------------------------------"} {printf "%-10s %-20s %-35s %-10s %.2f\n", $1, $2, $3, $4, $5}'
    
    echo ""
    
    # Show summary
    local count=$(echo "$snapshots" | jq length)
    local total_size=$(echo "$snapshots" | jq -r '.[].summary.total_bytes_processed' | awk '{sum+=$1} END {printf "%.2f", sum/1024/1024/1024}')
    local oldest=$(echo "$snapshots" | jq -r '.[0].time[:19]' 2>/dev/null)
    local newest=$(echo "$snapshots" | jq -r '.[-1].time[:19]' 2>/dev/null)
    
    echo -e "${YELLOW}Summary:${NC}"
    echo "  Total snapshots: $count"
    echo "  Total size: ${total_size}GB"
    if [ "$oldest" != "$newest" ]; then
        echo "  Date range: $oldest to $newest"
    else
        echo "  Date: $oldest"
    fi
}

show_repository_info() {
    log "Repository information:"
    echo ""
    
    # Repository stats
    restic stats --mode raw-data 2>/dev/null | head -10
    
    echo ""
    log "Repository status:"
    restic check --read-data-subset=1% 2>/dev/null && echo "✅ Repository is healthy" || echo "⚠️  Repository check failed or not available"
}

# Main script logic
main() {
    local service="${1:-}"
    
    if [ "$service" = "--help" ] || [ "$service" = "-h" ] || [ "$service" = "help" ]; then
        show_help
        exit 0
    fi
    
    # Check if we're in the backup directory or config exists
    if [ ! -f "$CONFIG_FILE" ]; then
        echo "Error: Configuration file not found: $CONFIG_FILE"
        echo "Make sure you're running this from the backup directory or have valid restic.conf"
        exit 1
    fi
    
    # Source Restic configuration
    source "$CONFIG_FILE"
    
    # Test repository access
    if ! restic snapshots >/dev/null 2>&1; then
        echo "Error: Cannot access Restic repository"
        echo "Check your configuration and repository password"
        exit 1
    fi
    
    # List snapshots
    if [ -n "$service" ]; then
        list_service_snapshots "$service"
    else
        list_all_snapshots
    fi
    
    # Show repository info
    echo ""
    show_repository_info
}

# Check for required tools
if ! command -v restic &> /dev/null; then
    echo "Error: restic is not installed or not in PATH"
    exit 1
fi

if ! command -v jq &> /dev/null; then
    echo "Error: jq is not installed (required for JSON parsing)"
    exit 1
fi

# Run main function
main "$@"