#!/usr/bin/env bash

set -euo pipefail

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

source "$SCRIPT_DIR/config.sh"
source "$REPO_ROOT/shared/minicorp/lib/minicorp.sh"
source "$REPO_ROOT/shared/minicorp/topologies/client-router-server.sh"

printf '\n'
mc_log "Setting up $LAB_NAME"

if [[ "$LAB_TOPOLOGY" != "client-router-server" ]]; then
    mc_error "Unsupported topology: $LAB_TOPOLOGY"
    exit 1
fi

# Verify the tools required by this lab.
for command_name in python3 dnsmasq ss curl getent dig; do
    mc_require_command "$command_name"
done

# Build the MiniCorp network from a known state.
# Suppress topology details so setup does not reveal investigation answers.
mc_log "Building MiniCorp virtual network"
mc_topology_client_router_server_up >/dev/null

# Verify the topology without exposing the investigation answers.
if ! mc_topology_client_router_server_check >/dev/null; then
    mc_error "MiniCorp topology validation failed."
    exit 1
fi

# Remove stale service output from a previous run.
sudo rm -f \
    "$LAB_WEB_STDOUT" \
    "$LAB_DNS_STDOUT"

#
# Web service
#

mc_log "Starting MiniCorp web service"

sudo ip netns exec "$MC_SERVER_NS" env \
    MINICORP_WEB_HOST="$MC_SERVER_ADDR" \
    MINICORP_WEB_PORT="$LAB_WEB_PORT" \
    python3 -u "$SCRIPT_DIR/web_server.py" \
    >"$LAB_WEB_STDOUT" 2>&1 &

web_ready=0

for attempt in {1..20}; do
    if mc_exec "$MC_SERVER_NS" ss -ltn |
        grep -F "$MC_SERVER_ADDR:$LAB_WEB_PORT" >/dev/null
    then
        web_ready=1
        break
    fi

    sleep 0.1
done

if [[ "$web_ready" -ne 1 ]]; then
    mc_error "Web service failed to start."

    if [[ -f "$LAB_WEB_STDOUT" ]]; then
        cat "$LAB_WEB_STDOUT" >&2
    fi

    exit 1
fi

#
# DNS service
#

mc_log "Starting MiniCorp DNS service"

sudo ip netns exec "$MC_ROUTER_NS" dnsmasq \
    --no-daemon \
    --interface="$MC_ROUTER_CLIENT_IF" \
    --listen-address="$MC_ROUTER_CLIENT_ADDR" \
    --bind-interfaces \
    --no-resolv \
    --no-hosts \
    --local=/minicorp.test/ \
    --host-record="$LAB_WEB_HOSTNAME,$MC_SERVER_ADDR" \
    --log-facility=- \
    >"$LAB_DNS_STDOUT" 2>&1 &

dns_ready=0

for attempt in {1..20}; do
    if mc_exec "$MC_ROUTER_NS" ss -lun |
        grep -F "$MC_ROUTER_CLIENT_ADDR:53" >/dev/null
    then
        dns_ready=1
        break
    fi

    sleep 0.1
done

if [[ "$dns_ready" -ne 1 ]]; then
    mc_error "DNS service failed to start."

    if [[ -f "$LAB_DNS_STDOUT" ]]; then
        cat "$LAB_DNS_STDOUT" >&2
    fi

    exit 1
fi

#
# Client resolver
#

mc_log "Configuring client DNS resolver"

sudo mkdir -p "$LAB_CLIENT_RESOLV_DIR"

printf 'nameserver %s\n' "$MC_ROUTER_CLIENT_ADDR" |
    sudo tee "$LAB_CLIENT_RESOLV_CONF" >/dev/null

#
# Final health check
#

if ! mc_exec "$MC_CLIENT_NS" \
    getent ahostsv4 "$LAB_WEB_HOSTNAME" >/dev/null
then
    mc_error "Client name resolution check failed."
    exit 1
fi

if ! mc_exec "$MC_CLIENT_NS" \
    curl --noproxy '*' -fsS \
    "http://$LAB_WEB_HOSTNAME:$LAB_WEB_PORT/" >/dev/null
then
    mc_error "Client web request check failed."
    exit 1
fi

printf '\n'
mc_log "$LAB_NAME is ready."