#!/usr/bin/env bash
# Held-out family evaluation for a model trained on the diffusion-only split.
#
# For a given checkpoint, runs three independent test passes — one per
# unseen family (3DMM/SadTalker, AE/EDTalk, Flow-Matching/Float) — and
# also runs an in-distribution diffusion test as a reference baseline
# (so you can directly read the cross-family gap from one CSV).
#
# Each pass produces:
#   * test/acc, test/auc on stdout
#   * AP, Acc@EER post-hoc from the predictions CSV
#   * fairness metrics (race4) — these are computed per pass; in-distribution
#     diffusion test will have the most reliable fairness numbers because
#     unseen-family tests intentionally use samples the model wasn't trained
#     to recognize.
#
# Output directory: outputs/cta_test_result/diffusion_holdout_<TS>/
#   ├── results.csv                        — combined long-table
#   ├── logs/<family>__<dataset>.log
#   └── runs/<family>/...                  — one subdir per (family, ckpt)
#
# Usage:
#   bash scripts/batch_test_diffusion_holdout.sh                                 # auto-discovers latest cta_diffusion_* run
#   bash scripts/batch_test_diffusion_holdout.sh outputs/cta_diffusion_2026.../  # explicit run dir
#   bash scripts/batch_test_diffusion_holdout.sh --ckpt /path/to/best.ckpt       # explicit ckpt
#   bash scripts/batch_test_diffusion_holdout.sh --num-top 1                     # only top-1 + last
#   bash scripts/batch_test_diffusion_holdout.sh --families sadtalker float      # subset
#   bash scripts/batch_test_diffusion_holdout.sh --include-diffusion             # also test on diffusion (in-distribution)
set -eo pipefail
cd "$(dirname "$0")/.."

[ -f .env ] && set -a && . ./.env && set +a

# ---- python interpreter -----------------------------------------------------
resolve_python() {
    if [[ -n "${PY:-}" ]] && "$PY" -c 'import hydra' >/dev/null 2>&1; then
        echo "$PY"; return
    fi
    if command -v python3 >/dev/null 2>&1 && python3 -c 'import hydra' >/dev/null 2>&1; then
        command -v python3; return
    fi
    if [[ -x /opt/conda/envs/av/bin/python3 ]] && \
       /opt/conda/envs/av/bin/python3 -c 'import hydra' >/dev/null 2>&1; then
        echo "/opt/conda/envs/av/bin/python3"; return
    fi
    cat <<EOF >&2
[holdout] FATAL: cannot find a Python interpreter with hydra installed.
  Activate the project env (e.g. \`conda activate pytorch\`) or pass PY=/path/to/python3.
EOF
    exit 1
}
PY="$(resolve_python)"
echo "[holdout] using python: $PY"

# ---- args -------------------------------------------------------------------
RUN_DIR=""
EXPLICIT_CKPT=""
NUM_TOP=3
FAMILIES=("sadtalker" "edtalk" "float")
INCLUDE_DIFFUSION=false

while [[ $# -gt 0 ]]; do
    case "$1" in
        --ckpt) EXPLICIT_CKPT="$2"; shift 2 ;;
        --num-top) NUM_TOP="$2"; shift 2 ;;
        --families)
            shift
            FAMILIES=()
            while [[ $# -gt 0 && "$1" != --* ]]; do FAMILIES+=("$1"); shift; done
            ;;
        --include-diffusion) INCLUDE_DIFFUSION=true; shift ;;
        -h|--help) grep -E '^#( |$)' "$0" | sed 's/^# \?//'; exit 0 ;;
        --*) echo "Unknown flag: $1" >&2; exit 1 ;;
        *) RUN_DIR="$1"; shift ;;
    esac
done

# ---- locate run dir / checkpoints ------------------------------------------
if [[ -z "$RUN_DIR" && -z "$EXPLICIT_CKPT" ]]; then
    # Auto-discover latest cta_diffusion_<TS> dir.
    RUN_DIR=$(ls -d outputs/cta_diffusion_[0-9]*_[0-9]* 2>/dev/null | sort -r | head -1 || true)
    if [[ -z "$RUN_DIR" ]]; then
        echo "[holdout] No cta_diffusion_* run dir found. Train first with bash scripts/train_cta_diffusion.sh, or pass an explicit --ckpt." >&2
        exit 1
    fi
fi

pick_ckpts() {
    local run_dir="$1" num_top="$2"
    local ckpt_dir="$run_dir/checkpoints"
    [[ -d "$ckpt_dir" ]] || return 0
    local top
    top=$(ls -1 "$ckpt_dir"/*.ckpt 2>/dev/null | grep -v '/last\.ckpt$' | sort -r || true)
    if [[ -n "$top" ]]; then
        local i=1
        while IFS= read -r p; do
            [[ -z "$p" ]] && continue
            echo "top${i}:$p"; i=$((i + 1))
            if (( i > num_top )); then break; fi
        done <<< "$top"
    fi
    [[ -f "$ckpt_dir/last.ckpt" ]] && echo "last:$ckpt_dir/last.ckpt"
}

if [[ -n "$EXPLICIT_CKPT" ]]; then
    [[ -f "$EXPLICIT_CKPT" ]] || { echo "[holdout] checkpoint not found: $EXPLICIT_CKPT" >&2; exit 1; }
    CKPTS=("custom:$EXPLICIT_CKPT")
    if [[ -z "$RUN_DIR" ]]; then RUN_DIR="$(dirname "$(dirname "$EXPLICIT_CKPT")")"; fi
else
    [[ -d "$RUN_DIR" ]] || { echo "[holdout] run dir not found: $RUN_DIR" >&2; exit 1; }
    mapfile -t CKPTS < <(pick_ckpts "$RUN_DIR" "$NUM_TOP")
    [[ ${#CKPTS[@]} -gt 0 ]] || { echo "[holdout] no checkpoints under $RUN_DIR/checkpoints" >&2; exit 1; }
fi

# ---- output layout ----------------------------------------------------------
TIMESTAMP="$(date +%Y%m%d_%H%M%S)"
BATCH_DIR="outputs/cta_test_result/diffusion_holdout_${TIMESTAMP}"
RESULTS_CSV="${BATCH_DIR}/results.csv"
LOG_DIR="${BATCH_DIR}/logs"
RUNS_DIR="${BATCH_DIR}/runs"
mkdir -p "$LOG_DIR" "$RUNS_DIR"

echo "============================================================"
echo "[holdout] run dir:        $RUN_DIR"
echo "[holdout] families:       ${FAMILIES[*]}"
$INCLUDE_DIFFUSION && echo "[holdout] also testing on diffusion (in-distribution)"
echo "[holdout] checkpoints:"
for c in "${CKPTS[@]}"; do echo "    $c"; done
echo "[holdout] output dir:     $BATCH_DIR"
echo "[holdout] results CSV:    $RESULTS_CSV"
echo "============================================================"

echo "family,ckpt_kind,ckpt_name,test_acc,test_auc,test_ap,test_acc_at_eer,F_FPR,F_OAE,F_DP,F_MEO,run_dir,test_out_dir,predictions_csv,timestamp" > "$RESULTS_CSV"

# ---- helpers ----------------------------------------------------------------
data_cfg_for() {
    case "$1" in
        sadtalker) echo "fairtalking_test_sadtalker" ;;
        edtalk)    echo "fairtalking_test_edtalk" ;;
        float)     echo "fairtalking_test_float" ;;
        diffusion) echo "fairtalking_diffusion_only" ;;
        *) echo ""; return 1 ;;
    esac
}

extract_metric() {
    local key="$1" output="$2"
    echo "$output" | grep -E "${key}[[:space:]]" | tail -1 | awk '{
        for (i=NF; i>=1; i--) if ($i ~ /^-?[0-9.]+$/) { print $i; exit }
    }' | tr -d '\r'
}
extract_kv() {
    local out="$1" key="$2"
    echo "$out" | tr ' ' '\n' | awk -F= -v k="$key" '$1==k {print $2; exit}' | tr -d '\r'
}
extract_fairness() {
    local csv="$1" key="$2"
    [[ -f "$csv" ]] || { echo ""; return; }
    awk -F, -v k="$key" '$1=="summary" && $(NF-1)==k {print $NF; exit}' "$csv" | tr -d '\r'
}

run_one() {
    local family="$1" ckpt_kind="$2" ckpt_path="$3"
    local data_cfg ts test_out_dir pred_csv log_path out rc
    local acc auc extra ap acc_eer f_fpr f_oae f_dp f_meo

    data_cfg=$(data_cfg_for "$family") || true
    if [[ -z "$data_cfg" ]]; then
        echo "[holdout] unknown family '$family'; skipping" >&2
        return
    fi
    ts="$(date +%Y%m%d_%H%M%S)"
    test_out_dir="${RUNS_DIR}/${family}/${ckpt_kind}__${ts}"
    mkdir -p "$test_out_dir"
    pred_csv="${test_out_dir}/test_predictions.csv"
    log_path="${LOG_DIR}/${family}__${ckpt_kind}.log"

    echo ""
    echo "[holdout] [$family] [$ckpt_kind] testing $(basename "$ckpt_path")"
    set +e
    out=$("$PY" src/train.py \
        method=cta \
        data="$data_cfg" \
        trainer=ddp \
        backbone=timesformer \
        +test_only=true \
        +test_ckpt="$ckpt_path" \
        +test_predictions_csv="$pred_csv" \
        output_dir="$test_out_dir" \
        hydra.run.dir="$test_out_dir/hydra" \
        experiment_name="cta_diffusion_holdout_${family}_${ckpt_kind}" \
        2>&1)
    rc=$?
    set -e
    echo "$out" > "$log_path"

    if [[ $rc -ne 0 ]]; then
        echo "${family},${ckpt_kind},$(basename "$ckpt_path"),ERROR_RC${rc},ERROR_RC${rc},ERROR_RC${rc},ERROR_RC${rc},,,,,$RUN_DIR,$test_out_dir,$pred_csv,$ts" >> "$RESULTS_CSV"
        echo "[holdout] [$family] [$ckpt_kind] FAILED (rc=$rc) — see $log_path"
        return
    fi

    acc=$(extract_metric "test/acc" "$out"); acc=${acc:-N/A}
    auc=$(extract_metric "test/auc" "$out"); auc=${auc:-N/A}

    ap="N/A"; acc_eer="N/A"
    if [[ -f "$pred_csv" ]]; then
        set +e
        extra=$("$PY" scripts/compute_extra_metrics.py "$pred_csv" 2>/dev/null)
        if [[ $? -eq 0 ]]; then
            ap=$(extract_kv "$extra" "ap"); ap=${ap:-N/A}
            acc_eer=$(extract_kv "$extra" "acc_at_eer"); acc_eer=${acc_eer:-N/A}
        fi
        set -e
    fi

    # Fairness only meaningful when race4 annotations cover the test split.
    # FairTalking's test.csv has them, so all 4 families' test sets carry race4.
    f_fpr=""; f_oae=""; f_dp=""; f_meo=""
    local fairness_csv="${pred_csv%.csv}_fairness.csv"
    f_fpr=$(extract_fairness "$fairness_csv" "F_FPR")
    f_oae=$(extract_fairness "$fairness_csv" "F_OAE")
    f_dp=$(extract_fairness  "$fairness_csv" "F_DP")
    f_meo=$(extract_fairness "$fairness_csv" "F_MEO")

    echo "${family},${ckpt_kind},$(basename "$ckpt_path"),${acc},${auc},${ap},${acc_eer},${f_fpr},${f_oae},${f_dp},${f_meo},$RUN_DIR,$test_out_dir,$pred_csv,$ts" >> "$RESULTS_CSV"
    echo "[holdout] [$family] [$ckpt_kind]  acc=$acc  auc=$auc  ap=$ap  acc_at_eer=$acc_eer"
}

# ---- main loop -------------------------------------------------------------
ALL_FAMILIES=()
$INCLUDE_DIFFUSION && ALL_FAMILIES+=("diffusion")
ALL_FAMILIES+=("${FAMILIES[@]}")

for fam in "${ALL_FAMILIES[@]}"; do
    for kp in "${CKPTS[@]}"; do
        ckpt_kind="${kp%%:*}"
        ckpt_path="${kp#*:}"
        run_one "$fam" "$ckpt_kind" "$ckpt_path"
    done
done

echo ""
echo "============================================================"
echo "[holdout] DONE.  results: $RESULTS_CSV"
echo "============================================================"
if command -v column >/dev/null 2>&1; then
    column -t -s, "$RESULTS_CSV" | head -40
else
    head -40 "$RESULTS_CSV"
fi