#!/bin/bash

# AWS Region
REGION="us-east-2"
TABLE_NAME="email-rules"

# Farben für Output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

# Logging-Funktionen
info() { echo -e "${GREEN}✓${NC} $1"; }
warn() { echo -e "${YELLOW}⚠${NC} $1"; }
error() { echo -e "${RED}✗${NC} $1"; exit 1; }

# Hilfe-Funktion
show_help() {
    cat << EOF
Usage: $0 <command> [options]

Commands:
  set-ooo <email> <message> [--html]
      Setzt Out-of-Office Nachricht
      --html: Nachricht ist HTML-formatiert (default: text)

  set-forward <email> <address1>[,address2,...]
      Setzt Forward-Adressen (überschreibt bestehende)

  add-forward <email> <address1>[,address2,...]
      Fügt Forward-Adressen hinzu (behält bestehende)

  remove-ooo <email>
      Entfernt Out-of-Office Regel

  remove-forward <email>
      Entfernt alle Forward-Adressen

  remove-all <email>
      Löscht komplette Regel (OOO + Forwards)

  show <email>
      Zeigt aktuelle Regel

  list
      Listet alle Regeln auf

Examples:
  $0 set-ooo john@example.com "I'm on vacation until Monday"
  $0 set-ooo john@example.com "<p>Out of office</p>" --html
  $0 set-forward john@example.com alice@example.com,bob@example.com
  $0 add-forward john@example.com charlie@example.com
  $0 show john@example.com
  $0 remove-all john@example.com

EOF
}

# Prüft ob Regel existiert
rule_exists() {
    local email=$1
    aws dynamodb get-item \
        --table-name "$TABLE_NAME" \
        --key '{"email_address": {"S": "'"$email"'"}}' \
        --region "$REGION" \
        --output json 2>/dev/null | jq -e '.Item' > /dev/null
}

# Holt aktuelle Regel
get_rule() {
    local email=$1
    aws dynamodb get-item \
        --table-name "$TABLE_NAME" \
        --key '{"email_address": {"S": "'"$email"'"}}' \
        --region "$REGION" \
        --output json 2>/dev/null | jq -r '.Item // {}'
}

# Validiert E-Mail-Adresse (basic)
validate_email() {
    local email=$1
    if [[ ! "$email" =~ ^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$ ]]; then
        error "Ungültige E-Mail-Adresse: $email"
    fi
}

# ==============================================
# COMMAND: set-ooo
# ==============================================
cmd_set_ooo() {
    local email=$1
    local message=$2
    local content_type="text"
    
    if [ "$3" = "--html" ]; then
        content_type="html"
    fi
    
    if [ -z "$email" ] || [ -z "$message" ]; then
        error "Usage: $0 set-ooo <email> <message> [--html]"
    fi
    
    validate_email "$email"
    
    # Hole bestehende Forwards (falls vorhanden)
    local existing_rule=$(get_rule "$email")
    local forwards_json='{"L": []}'
    
    if [ "$existing_rule" != "{}" ]; then
        forwards_json=$(echo "$existing_rule" | jq -r '.forwards // {"L": []}')
        warn "Regel existiert bereits, behalte bestehende Forwards bei"
    fi
    
    # Setze Regel
    aws dynamodb put-item \
        --table-name "$TABLE_NAME" \
        --item '{
            "email_address": {"S": "'"$email"'"},
            "ooo_active": {"BOOL": true},
            "ooo_message": {"S": "'"${message//\"/\\\"}"'"},
            "ooo_content_type": {"S": "'"$content_type"'"},
            "forwards": '"$forwards_json"',
            "last_updated": {"S": "'$(date -u +"%Y-%m-%dT%H:%M:%SZ")'"}
        }' \
        --region "$REGION" >/dev/null
    
    info "Out-of-Office aktiviert für $email ($content_type)"
}

# ==============================================
# COMMAND: set-forward
# ==============================================
cmd_set_forward() {
    local email=$1
    local forward_addresses=$2
    
    if [ -z "$email" ] || [ -z "$forward_addresses" ]; then
        error "Usage: $0 set-forward <email> <address1>[,address2,...]"
    fi
    
    validate_email "$email"
    
    # Validiere alle Forward-Adressen
    IFS=',' read -ra ADDRS <<< "$forward_addresses"
    for addr in "${ADDRS[@]}"; do
        validate_email "$(echo "$addr" | xargs)"  # xargs trimmt whitespace
    done
    
    # Konvertiere zu JSON-Array
    local forwards_list=$(echo "$forward_addresses" | jq -R 'split(",") | map(gsub("^\\s+|\\s+$";"")) | map({"S": .})')
    
    # Hole bestehende OOO-Einstellungen (falls vorhanden)
    local existing_rule=$(get_rule "$email")
    local ooo_active="false"
    local ooo_message=""
    local ooo_content_type="text"
    
    if [ "$existing_rule" != "{}" ]; then
        ooo_active=$(echo "$existing_rule" | jq -r '.ooo_active.BOOL // false')
        ooo_message=$(echo "$existing_rule" | jq -r '.ooo_message.S // ""')
        ooo_content_type=$(echo "$existing_rule" | jq -r '.ooo_content_type.S // "text"')
        warn "Regel existiert bereits, behalte bestehende OOO-Einstellungen bei"
    fi
    
    # Setze Regel
    aws dynamodb put-item \
        --table-name "$TABLE_NAME" \
        --item '{
            "email_address": {"S": "'"$email"'"},
            "ooo_active": {"BOOL": '"$ooo_active"'},
            "ooo_message": {"S": "'"${ooo_message//\"/\\\"}"'"},
            "ooo_content_type": {"S": "'"$ooo_content_type"'"},
            "forwards": {"L": '"$forwards_list"'},
            "last_updated": {"S": "'$(date -u +"%Y-%m-%dT%H:%M:%SZ")'"}
        }' \
        --region "$REGION" >/dev/null
    
    info "Forwards gesetzt für $email: ${ADDRS[*]}"
}

# ==============================================
# COMMAND: add-forward
# ==============================================
cmd_add_forward() {
    local email=$1
    local new_addresses=$2
    
    if [ -z "$email" ] || [ -z "$new_addresses" ]; then
        error "Usage: $0 add-forward <email> <address1>[,address2,...]"
    fi
    
    validate_email "$email"
    
    if ! rule_exists "$email"; then
        error "Keine Regel für $email gefunden. Nutze 'set-forward' stattdessen."
    fi
    
    # Hole bestehende Forwards
    local existing_rule=$(get_rule "$email")
    local existing_forwards=$(echo "$existing_rule" | jq -r '.forwards.L // [] | map(.S) | join(",")')
    
    # Kombiniere und dedupliziere
    local combined="$existing_forwards,$new_addresses"
    IFS=',' read -ra ALL_ADDRS <<< "$combined"
    
    # Dedupliziere und validiere
    declare -A seen
    local unique_addrs=()
    for addr in "${ALL_ADDRS[@]}"; do
        addr=$(echo "$addr" | xargs)  # Trim whitespace
        if [ -n "$addr" ] && [ -z "${seen[$addr]}" ]; then
            validate_email "$addr"
            seen[$addr]=1
            unique_addrs+=("$addr")
        fi
    done
    
    # Konvertiere zu Komma-separiertem String
    local final_list=$(IFS=','; echo "${unique_addrs[*]}")
    
    # Nutze set-forward mit kombinierter Liste
    cmd_set_forward "$email" "$final_list"
    info "Forwards hinzugefügt (insgesamt ${#unique_addrs[@]} Adressen)"
}

# ==============================================
# COMMAND: remove-ooo
# ==============================================
cmd_remove_ooo() {
    local email=$1
    
    if [ -z "$email" ]; then
        error "Usage: $0 remove-ooo <email>"
    fi
    
    validate_email "$email"
    
    if ! rule_exists "$email"; then
        warn "Keine Regel für $email gefunden"
        return 0
    fi
    
    # Update: OOO deaktivieren, Message-Felder entfernen
    aws dynamodb update-item \
        --table-name "$TABLE_NAME" \
        --key '{"email_address": {"S": "'"$email"'"}}' \
        --update-expression "SET ooo_active = :false, last_updated = :timestamp REMOVE ooo_message, ooo_content_type" \
        --expression-attribute-values '{
            ":false": {"BOOL": false},
            ":timestamp": {"S": "'$(date -u +"%Y-%m-%dT%H:%M:%SZ")'"}
        }' \
        --region "$REGION" >/dev/null
    
    info "Out-of-Office entfernt für $email"
}

# ==============================================
# COMMAND: remove-forward
# ==============================================
cmd_remove_forward() {
    local email=$1
    
    if [ -z "$email" ]; then
        error "Usage: $0 remove-forward <email>"
    fi
    
    validate_email "$email"
    
    if ! rule_exists "$email"; then
        warn "Keine Regel für $email gefunden"
        return 0
    fi
    
    # Update: Forwards leeren
    aws dynamodb update-item \
        --table-name "$TABLE_NAME" \
        --key '{"email_address": {"S": "'"$email"'"}}' \
        --update-expression "SET forwards = :empty, last_updated = :timestamp" \
        --expression-attribute-values '{
            ":empty": {"L": []},
            ":timestamp": {"S": "'$(date -u +"%Y-%m-%dT%H:%M:%SZ")'"}
        }' \
        --region "$REGION" >/dev/null
    
    info "Forwards entfernt für $email"
}

# ==============================================
# COMMAND: remove-all
# ==============================================
cmd_remove_all() {
    local email=$1
    
    if [ -z "$email" ]; then
        error "Usage: $0 remove-all <email>"
    fi
    
    validate_email "$email"
    
    if ! rule_exists "$email"; then
        warn "Keine Regel für $email gefunden"
        return 0
    fi
    
    aws dynamodb delete-item \
        --table-name "$TABLE_NAME" \
        --key '{"email_address": {"S": "'"$email"'"}}' \
        --region "$REGION" >/dev/null
    
    info "Regel komplett gelöscht für $email"
}

# ==============================================
# COMMAND: show
# ==============================================
cmd_show() {
    local email=$1
    
    if [ -z "$email" ]; then
        error "Usage: $0 show <email>"
    fi
    
    validate_email "$email"
    
    if ! rule_exists "$email"; then
        warn "Keine Regel für $email gefunden"
        return 0
    fi
    
    local rule=$(get_rule "$email")
    
    echo ""
    echo "Regel für: $email"
    echo "─────────────────────────────────────────"
    
    # OOO Status
    local ooo_active=$(echo "$rule" | jq -r '.ooo_active.BOOL // false')
    if [ "$ooo_active" = "true" ]; then
        local ooo_msg=$(echo "$rule" | jq -r '.ooo_message.S // ""')
        local ooo_type=$(echo "$rule" | jq -r '.ooo_content_type.S // "text"')
        echo "Out-of-Office: ${GREEN}AKTIV${NC} ($ooo_type)"
        echo "Nachricht: $ooo_msg"
    else
        echo "Out-of-Office: ${RED}INAKTIV${NC}"
    fi
    
    # Forwards
    local forwards=$(echo "$rule" | jq -r '.forwards.L // [] | map(.S) | join(", ")')
    if [ -n "$forwards" ]; then
        echo "Forwards: $forwards"
    else
        echo "Forwards: ${RED}KEINE${NC}"
    fi
    
    # Letztes Update
    local updated=$(echo "$rule" | jq -r '.last_updated.S // "unbekannt"')
    echo "Letzte Änderung: $updated"
    echo ""
}

# ==============================================
# COMMAND: list
# ==============================================
cmd_list() {
    echo ""
    echo "Alle E-Mail-Regeln:"
    echo "═════════════════════════════════════════════════════════════════"
    
    local items=$(aws dynamodb scan \
        --table-name "$TABLE_NAME" \
        --region "$REGION" \
        --output json | jq -r '.Items')
    
    local count=$(echo "$items" | jq 'length')
    
    if [ "$count" -eq 0 ]; then
        warn "Keine Regeln gefunden"
        echo ""
        return 0
    fi
    
    echo "$items" | jq -r '.[] | 
        "\(.email_address.S)\n" +
        "  OOO: \(if .ooo_active.BOOL then "✓ AKTIV (\(.ooo_content_type.S // "text"))" else "✗ INAKTIV" end)\n" +
        "  Forwards: \(if (.forwards.L | length) > 0 then (.forwards.L | map(.S) | join(", ")) else "KEINE" end)\n" +
        "  Updated: \(.last_updated.S // "unbekannt")\n"'
    
    echo "─────────────────────────────────────────────────────────────────"
    echo "Gesamt: $count Regel(n)"
    echo ""
}

# ==============================================
# MAIN
# ==============================================
COMMAND=$1
shift

case "$COMMAND" in
    set-ooo)
        cmd_set_ooo "$@"
        ;;
    set-forward)
        cmd_set_forward "$@"
        ;;
    add-forward)
        cmd_add_forward "$@"
        ;;
    remove-ooo)
        cmd_remove_ooo "$@"
        ;;
    remove-forward)
        cmd_remove_forward "$@"
        ;;
    remove-all)
        cmd_remove_all "$@"
        ;;
    show)
        cmd_show "$@"
        ;;
    list)
        cmd_list
        ;;
    help|--help|-h|"")
        show_help
        ;;
    *)
        error "Unbekannter Befehl: $COMMAND\n\nNutze '$0 help' für Hilfe"
        ;;
esac