#!/bin/bash
# ============================================================================
# Teste de Stress - Demonstração de Traffic Splitting do Istio
# ============================================================================
# Script interativo para visualizar a distribuição de tráfego entre v1 e v2.
#
# Uso:
#   ./teste-stress.sh [URL] [NUM_REQUESTS]
#
# Exemplos:
#   ./teste-stress.sh                        # Usa APP_HOST do .env, 100 requests
#   ./teste-stress.sh https://app.kube.quest # URL específica, 100 requests
#   ./teste-stress.sh https://app.kube.quest 50  # 50 requests
# ============================================================================

set -e

RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
CYAN='\033[0;36m'
MAGENTA='\033[0;35m'
NC='\033[0m'
BOLD='\033[1m'

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
ENV_FILE="${SCRIPT_DIR}/.env"

# ============================================================================
# Configuração
# ============================================================================

# Carregar .env se existir
if [[ -f "$ENV_FILE" ]]; then
    source "$ENV_FILE"
fi

# Parâmetros
URL="${1:-}"
NUM_REQUESTS="${2:-100}"

# Se URL não foi passada, tentar construir do .env
if [[ -z "$URL" ]]; then
    if [[ -n "$APP_HOST" ]]; then
        if [[ "$USE_LETSENCRYPT" == "true" ]]; then
            URL="https://${APP_HOST}"
        else
            URL="http://${APP_HOST}"
        fi
    else
        echo -e "${RED}[ERRO]${NC} URL não especificada e APP_HOST não encontrado no .env"
        echo ""
        echo "Uso: $0 [URL] [NUM_REQUESTS]"
        echo ""
        echo "Exemplos:"
        echo "  $0 https://app.kube.quest"
        echo "  $0 https://app.kube.quest 50"
        echo ""
        echo "Ou configure APP_HOST no .env executando setup.sh novamente."
        exit 1
    fi
fi

# ============================================================================
# Funções
# ============================================================================

get_current_weights() {
    local weights
    weights=$(kubectl get virtualservice app-backend -n istio -o jsonpath='{.spec.http[0].route[*].weight}' 2>/dev/null || echo "90 10")
    echo "$weights"
}

draw_bar() {
    local value=$1
    local max=$2
    local width=40
    local filled=$((value * width / max))
    local empty=$((width - filled))

    printf "["
    for ((i=0; i<filled; i++)); do printf "${GREEN}#${NC}"; done
    for ((i=0; i<empty; i++)); do printf "."; done
    printf "]"
}

show_header() {
    local weights
    weights=$(get_current_weights)
    local v1_weight=$(echo "$weights" | awk '{print $1}')
    local v2_weight=$(echo "$weights" | awk '{print $2}')

    echo ""
    echo -e "${CYAN}${BOLD}╔═══════════════════════════════════════════════════════════╗${NC}"
    echo -e "${CYAN}${BOLD}║  Teste de Traffic Splitting - Istio                        ║${NC}"
    echo -e "${CYAN}${BOLD}╚═══════════════════════════════════════════════════════════╝${NC}"
    echo ""
    echo -e "${YELLOW}Distribuição configurada:${NC} v1=${v1_weight}% v2=${v2_weight}%"
    echo -e "${YELLOW}URL:${NC} ${URL}"
    echo -e "${YELLOW}Requests:${NC} ${NUM_REQUESTS}"
    echo ""
    echo -e "${CYAN}───────────────────────────────────────────────────────────${NC}"
}

run_test() {
    local count_v1=0
    local count_v2=0
    local count_other=0

    for ((i=1; i<=NUM_REQUESTS; i++)); do
        # Fazer request e capturar resposta
        local response
        response=$(curl -sk --connect-timeout 5 --max-time 10 "$URL" 2>/dev/null || echo "ERROR")

        # Identificar versão baseado na resposta
        if echo "$response" | grep -q "v1\|node-bugado v1"; then
            ((count_v1++))
        elif echo "$response" | grep -q "v2\|stable\|node-bugado v2"; then
            ((count_v2++))
        else
            ((count_other++))
        fi

        # Exibir progresso
        printf "\r${NC}[%3d/%d] ${BLUE}v1:%-3d${NC} ${GREEN}v2:%-3d${NC}" "$i" "$NUM_REQUESTS" "$count_v1" "$count_v2"

        # Pequena pausa para não sobrecarregar
        sleep 0.05
    done

    echo ""
    echo ""

    # Exibir resultados
    show_results "$count_v1" "$count_v2" "$count_other"
}

show_results() {
    local count_v1=$1
    local count_v2=$2
    local count_other=$3
    local total=$((count_v1 + count_v2 + count_other))

    local pct_v1=0
    local pct_v2=0
    [[ $total -gt 0 ]] && pct_v1=$((count_v1 * 100 / total))
    [[ $total -gt 0 ]] && pct_v2=$((count_v2 * 100 / total))

    echo -e "${CYAN}═══════════════════════════════════════════════════════════${NC}"
    echo -e "${BOLD}Resultados:${NC}"
    echo ""
    printf "  ${BLUE}v1${NC}: %3d (%2d%%)  " "$count_v1" "$pct_v1"
    draw_bar "$count_v1" "$total"
    echo ""
    printf "  ${GREEN}v2${NC}: %3d (%2d%%)  " "$count_v2" "$pct_v2"
    draw_bar "$count_v2" "$total"
    echo ""

    if [[ $count_other -gt 0 ]]; then
        echo -e "  ${RED}Erros${NC}: $count_other"
    fi

    echo -e "${CYAN}═══════════════════════════════════════════════════════════${NC}"
    echo ""

    # Comandos para alterar distribuição
    show_commands
}

show_commands() {
    echo -e "${BOLD}Comandos para alterar distribuição:${NC}"
    echo ""
    echo -e "${YELLOW}# Aumentar tráfego para v2 (50/50)${NC}"
    echo "kubectl patch virtualservice app-backend -n istio --type='json' \\"
    echo "  -p='[{\"op\":\"replace\",\"path\":\"/spec/http/0/route/0/weight\",\"value\":50},"
    echo "      {\"op\":\"replace\",\"path\":\"/spec/http/0/route/1/weight\",\"value\":50}]'"
    echo ""
    echo -e "${YELLOW}# Virada completa para v2 (0/100)${NC}"
    echo "kubectl patch virtualservice app-backend -n istio --type='json' \\"
    echo "  -p='[{\"op\":\"replace\",\"path\":\"/spec/http/0/route/0/weight\",\"value\":0},"
    echo "      {\"op\":\"replace\",\"path\":\"/spec/http/0/route/1/weight\",\"value\":100}]'"
    echo ""
    echo -e "${YELLOW}# Rollback para v1 se necessário (100/0)${NC}"
    echo "kubectl patch virtualservice app-backend -n istio --type='json' \\"
    echo "  -p='[{\"op\":\"replace\",\"path\":\"/spec/http/0/route/0/weight\",\"value\":100},"
    echo "      {\"op\":\"replace\",\"path\":\"/spec/http/0/route/1/weight\",\"value\":0}]'"
    echo ""
    echo -e "${CYAN}Após alterar, re-execute: ${NC}${BOLD}./teste-stress.sh${NC}"
    echo ""
}

# ============================================================================
# Execução
# ============================================================================

show_header
run_test