#!/usr/bin/env bash
# Disposable, headless smoke check for the incomplete 26.3 runtime Age backend.
set -euo pipefail

repo_dir=$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)
smoke_dir=$(mktemp -d "${TMPDIR:-/tmp}/rivencraft-263-smoke.XXXXXX")
server_dir="$smoke_dir/server"
server_pid=
input_fd=

cleanup() {
    if [[ -n "$server_pid" ]] && kill -0 "$server_pid" 2>/dev/null; then
        if [[ -n "$input_fd" ]]; then printf 'stop\n' >&"$input_fd" || true; fi
        wait "$server_pid" 2>/dev/null || true
    fi
    if [[ -n "$input_fd" ]]; then exec {input_fd}>&-; fi
    rm -rf -- "$smoke_dir"
}
trap cleanup EXIT

mkdir -p "$server_dir"
printf 'eula=true\n' > "$server_dir/eula.txt"
printf 'server-port=0\nonline-mode=false\nwhite-list=false\n' > "$server_dir/server.properties"

wait_for_log() {
    local log_file=$1 pattern=$2 seconds=$3
    local tries=$((seconds * 4))
    for ((i = 0; i < tries; i++)); do
        if grep -Fq -- "$pattern" "$log_file" 2>/dev/null; then return 0; fi
        if ! kill -0 "$server_pid" 2>/dev/null; then
            printf 'Server exited before: %s\n' "$pattern" >&2
            tail -80 "$log_file" >&2
            return 1
        fi
        sleep 0.25
    done
    printf 'Timed out waiting for: %s\n' "$pattern" >&2
    tail -80 "$log_file" >&2
    return 1
}

start_server() {
    local phase=$1
    log_file="$smoke_dir/$phase.log"
    fifo="$smoke_dir/$phase.stdin"
    mkfifo "$fifo"
    exec {input_fd}<>"$fifo"
    "$repo_dir/gradlew" -p "$repo_dir/ports/mc263" runServer \
        -PserverRunDir="$server_dir" --no-daemon < "$fifo" > "$log_file" 2>&1 &
    server_pid=$!
    wait_for_log "$log_file" 'Done (' 120
}

stop_server() {
    printf 'stop\n' >&"$input_fd"
    wait "$server_pid"
    server_pid=
    exec {input_fd}>&-
    rm -- "$fifo"
}

send_and_wait() {
    local command=$1 result=$2
    printf '%s\n' "$command" >&"$input_fd"
    wait_for_log "$log_file" "$result" 60
}

start_server first
send_and_wait 'rivencraft_port compat' 'Registered biomes by namespace:'
send_and_wait 'rivencraft_port age create smoke_alpha 123456789' 'Created rivencraft:age/smoke_alpha with seed 123456789'
send_and_wait 'rivencraft_port age create smoke_beta 987654321' 'Created rivencraft:age/smoke_beta with seed 987654321'
# The index must reach disk while the server is still running. A graceful
# shutdown would hide the interrupted-save regression this checks.
index_file="$server_dir/world/dimensions/minecraft/overworld/data/rivencraft/runtime_ages.dat"
[[ -s "$index_file" ]] || {
    printf 'Age index was not persisted before shutdown: %s\n' "$index_file" >&2
    exit 1
}
gzip -dc "$index_file" | strings | grep -Fq 'rivencraft:age/smoke_alpha'
gzip -dc "$index_file" | strings | grep -Fq 'rivencraft:age/smoke_beta'
send_and_wait 'rivencraft_port age sample smoke_alpha' 'rivencraft:age/smoke_alpha seed=123456789 chunkOffset=0 terrain='
send_and_wait 'rivencraft_port age sample smoke_beta' 'rivencraft:age/smoke_beta seed=987654321 chunkOffset=0 terrain='
alpha_before=$(grep -F 'rivencraft:age/smoke_alpha seed=123456789 chunkOffset=0 terrain=' "$log_file" | tail -1 | sed 's/.*terrain=//')
beta_before=$(grep -F 'rivencraft:age/smoke_beta seed=987654321 chunkOffset=0 terrain=' "$log_file" | tail -1 | sed 's/.*terrain=//')
if [[ "$alpha_before" == "$beta_before" ]]; then
    printf 'Different Age seeds produced the same terrain probe: %s\n' "$alpha_before" >&2
    exit 1
fi
stop_server

start_server restart
send_and_wait 'rivencraft_port age list' 'smoke_alpha'
send_and_wait 'rivencraft_port age sample smoke_alpha' 'rivencraft:age/smoke_alpha seed=123456789 chunkOffset=0 terrain='
send_and_wait 'rivencraft_port age sample smoke_beta' 'rivencraft:age/smoke_beta seed=987654321 chunkOffset=0 terrain='
alpha_after=$(grep -F 'rivencraft:age/smoke_alpha seed=123456789 chunkOffset=0 terrain=' "$log_file" | tail -1 | sed 's/.*terrain=//')
beta_after=$(grep -F 'rivencraft:age/smoke_beta seed=987654321 chunkOffset=0 terrain=' "$log_file" | tail -1 | sed 's/.*terrain=//')
[[ "$alpha_before" == "$alpha_after" && "$beta_before" == "$beta_after" ]] || {
    printf 'Age terrain changed across restart: %s/%s -> %s/%s\n' \
        "$alpha_before" "$beta_before" "$alpha_after" "$beta_after" >&2
    exit 1
}
stop_server
printf '26.3 dedicated-server smoke passed: two distinct Ages persisted across restart.\n'