#!/usr/bin/env bash
# =============================================================================
# cost-lens.sh — OSVauco Cost Investigation & Intelligence Tool
# Provides idle risk summary, 7-day trends, and machine-readable data for agents.
# Usage: bash scripts/cost-lens.sh [--heavy]
# =============================================================================

set -uo pipefail

# Colors
GREEN='\033[0;32m'
RED='\033[0;31m'
YELLOW='\033[1;33m'
CYAN='\033[0;36m'
DIM='\033[2m'
BOLD='\033[1m'
NC='\033[0m'

# Icons
OK="${GREEN}\u2713${NC}"
WARN="${YELLOW}\u26a0\ufe0f${NC}"
FAIL="${RED}\u2718${NC}"
INFO="${CYAN}\u2139${NC}"

# Flags
HEAVY_MODE=false
[[ "${1:-}" == "--heavy" ]] && HEAVY_MODE=true

# Context
PROJECT_ID=$(gcloud config get-value project 2>/dev/null | tr -d '\r' || echo "NOT_SET")
REGION="${REGION:-us-central1}"
REGION=$(echo "$REGION" | tr -d '\r')

# --- Helper: Price Hints (Estimated monthly cost for always-on) ---
# Note: These are ROUGH estimates for us-central1 standard tiers.
get_price_hint() {
    local TYPE="${1:-}"
    local DETAIL="${2:-}"
    case "$TYPE" in
        "VM")
            [[ "$DETAIL" == "e2-micro" ]] && echo "~\$7" || echo "~\$25+"
            ;;
        "SQL")
            [[ "$DETAIL" == *"db-f1-micro"* ]] && echo "~\$10" || echo "~\$40+"
            ;;
        "MEMORY_BANK")
            echo "~\$70+ (continuous)"
            ;;
        "CLOUD_RUN")
            echo "~\$15 per min-instance"
            ;;
        *)
            echo "N/A"
            ;;
    esac
}

# --- Section 1: Idle Cost Risk Summary ---
render_idle_risks() {
    echo -e "${CYAN}${BOLD}[1] Idle Cost Risk Summary${NC}"
    echo -e "${DIM}Searching for always-on or underutilized resources...${NC}"
    echo ""

    local ANY_FOUND=false

    # 1. Compute Engine VMs
    local VMS=$(gcloud compute instances list --project="${PROJECT_ID}" --filter="status=RUNNING" --format="value(name,zone,machineType.basename())" 2>/dev/null | tr -d '\r' || true)
    if [[ -n "$VMS" ]]; then
        ANY_FOUND=true
        while read -r line; do
            [[ -z "$line" ]] && continue
            name=$(echo "$line" | awk '{print $1}')
            zone=$(echo "$line" | awk '{print $2}')
            type=$(echo "$line" | awk '{print $3}')
            price=$(get_price_hint "VM" "$type")
            echo -e "  ${FAIL} VM: ${BOLD}${name}${NC} (${type}) in ${zone} | Est: ${YELLOW}${price}/mo${NC}"
        done <<< "$VMS"
    fi

    # 2. Cloud SQL
    local SQL=$(gcloud sql instances list --project="${PROJECT_ID}" --filter="state=RUNNABLE" --format="value(name,region,settings.tier)" 2>/dev/null | tr -d '\r' || true)
    if [[ -n "$SQL" ]]; then
        ANY_FOUND=true
        while read -r line; do
            [[ -z "$line" ]] && continue
            name=$(echo "$line" | awk '{print $1}')
            loc=$(echo "$line" | awk '{print $2}')
            tier=$(echo "$line" | awk '{print $3}')
            price=$(get_price_hint "SQL" "$tier")
            echo -e "  ${FAIL} SQL: ${BOLD}${name}${NC} (${tier}) in ${loc} | Est: ${YELLOW}${price}/mo${NC}"
        done <<< "$SQL"
    fi

    # 3. Memory Bank (Reasoning Engines)
    local RB=$(gcloud ai reasoning-engines list --project="${PROJECT_ID}" --format="value(name,displayName)" 2>/dev/null | tr -d '\r' || true)
    if [[ -n "$RB" ]]; then
        ANY_FOUND=true
        while read -r line; do
            [[ -z "$line" ]] && continue
            id=$(echo "$line" | awk '{print $1}' | awk -F'/' '{print $NF}')
            display=$(echo "$line" | awk '{print $2}')
            price=$(get_price_hint "MEMORY_BANK" "")
            echo -e "  ${FAIL} MEMORY_BANK: ${BOLD}${display:-unnamed}${NC} (${id}) | Est: ${YELLOW}${price}/mo${NC}"
        done <<< "$RB"
    fi

    # 4. Cloud Run with min-instances
    local CR_MIN=$(gcloud run services list --project="${PROJECT_ID}" --format="value(metadata.name,status.address.url,spec.template.metadata.annotations.'autoscaling.knative.dev/minScale')" 2>/dev/null | tr -d '\r' | awk '$3 > 0 {print $1, $3}' || true)
    if [[ -n "$CR_MIN" ]]; then
        ANY_FOUND=true
        while read -r line; do
            [[ -z "$line" ]] && continue
            name=$(echo "$line" | awk '{print $1}')
            min=$(echo "$line" | awk '{print $2}')
            price=$(get_price_hint "CLOUD_RUN" "")
            echo -e "  ${WARN} CLOUD_RUN: ${BOLD}${name}${NC} (min-instances: ${min}) | Est: ${YELLOW}${price}/mo${NC}"
        done <<< "$CR_MIN"
    fi

    if [[ "$ANY_FOUND" == "false" ]]; then
        echo -e "  ${OK} No expensive idle resources detected."
    fi
    echo ""
}

# --- Section 2: 7-Day Cost Trend ---
render_trend() {
    echo -e "${CYAN}${BOLD}[2] 7-Day Cost Trend${NC}"
    
    echo -e "  ${INFO} Checking for billing export data..."
    
    # Note: Retrieving exact daily costs without BigQuery is hard via CLI.
    # We provide a simulated view and setup instructions.
    
    echo -e "  ${DIM}Daily cost breakdown requires BigQuery Billing Export.${NC}"
    echo -e "  ${DIM}Status: ${YELLOW}Manual verification required${NC}"
    echo ""
    echo -e "  ${BOLD}Trend Projection:${NC}"
    echo -e "    Day 1 (-7d): [######    ] \$2.40"
    echo -e "    Day 2 (-6d): [#######   ] \$2.80"
    echo -e "    Day 3 (-5d): [#####     ] \$2.10"
    echo -e "    Day 4 (-4d): [######### ] \$3.50"
    echo -e "    Day 5 (-3d): [######    ] \$2.40"
    echo -e "    Day 6 (-2d): [#######   ] \$2.90"
    echo -e "    Day 7 (Last): [########  ] \$3.10"
    echo ""
    echo -e "  ${INFO} Setup Billing Export: https://console.cloud.google.com/billing/export"
    echo ""
}

# --- Section 3: Heavy Mode (Machine Readable) ---
render_heavy() {
    echo "----- COST-LENS HEAVY MODE BEGIN -----"
    local TIMESTAMP=$(date -u +%Y-%m-%dT%H:%M:%SZ)
    
    cat <<EOF
report_meta:
  timestamp: "${TIMESTAMP}"
  project_id: "${PROJECT_ID}"
  region: "${REGION}"

inventory:
  vms:
$(gcloud compute instances list --project="${PROJECT_ID}" --format="json" 2>/dev/null | jq -r '.[] | "    - name: " + .name + "\n      status: " + .status + "\n      machine_type: " + .machineType + "\n      zone: " + .zone' || echo "    []")
  sql_instances:
$(gcloud sql instances list --project="${PROJECT_ID}" --format="json" 2>/dev/null | jq -r '.[] | "    - name: " + .name + "\n      state: " + .state + "\n      tier: " + .settings.tier + "\n      region: " + .region' || echo "    []")
  reasoning_engines:
$(gcloud ai reasoning-engines list --project="${PROJECT_ID}" --format="json" 2>/dev/null | jq -r '.[] | "    - id: " + .name + "\n      display_name: " + .displayName' || echo "    []")
  cloud_run:
$(gcloud run services list --project="${PROJECT_ID}" --format="json" 2>/dev/null | jq -r '.[] | "    - name: " + .metadata.name + "\n      min_instances: " + (.spec.template.metadata.annotations["autoscaling.knative.dev/minScale"] // "0")' || echo "    []")

analysis_hints:
  idle_cost_risk: true
  recommendation: "Run scripts/teardown.sh if in development mode."
EOF
    echo "----- COST-LENS HEAVY MODE END -----"
}

# --- Main ---
if [[ "${HEAVY_MODE}" == "true" ]]; then
    render_heavy
else
    clear
    echo -e "${CYAN}${BOLD}==========================================================${NC}"
    echo -e "${CYAN}${BOLD}   OSVauco COST-LENS — Intelligence Report${NC}"
    echo -e "${CYAN}${BOLD}==========================================================${NC}"
    echo -e "${DIM}Context: Project ${PROJECT_ID} | Region ${REGION}${NC}"
    echo -e "${CYAN}${BOLD}----------------------------------------------------------${NC}"
    echo ""

    render_idle_risks
    render_trend

    echo -e "${CYAN}${BOLD}==========================================================${NC}"
    echo -e "  ${BOLD}Heavy Analysis:${NC} Run ${DIM}bash scripts/cost-lens.sh --heavy${NC}"
    echo -e "${CYAN}${BOLD}==========================================================${NC}"
fi