#!/usr/bin/env bash
# Sides are encoded individually — no concatenation. Idempotent: a side is
# skipped if its output is newer than its source.
set -euo pipefail

REPO_ROOT="$(cd "$(dirname "$0")/.." && pwd)"
MANIFEST="${MANIFEST:-$REPO_ROOT/content/audio.yaml}"
RAW_DIR="${RAW_DIR:-$REPO_ROOT/content/audio}"
OUT_DIR="${OUT_DIR:-$REPO_ROOT/web/static/audio}"

for tool in yq ffmpeg; do
	if ! command -v "$tool" >/dev/null; then
		echo "error: $tool not in PATH (try: nix develop)" >&2
		exit 1
	fi
done

if [[ ! -f "$MANIFEST" ]]; then
	echo "error: manifest not found: $MANIFEST" >&2
	exit 1
fi

mkdir -p "$OUT_DIR"

DEFAULT_BITRATE=$(yq -r '.defaults.bitrate // "64k"' "$MANIFEST")
DEFAULT_CHANNELS=$(yq -r '.defaults.channels // "2"' "$MANIFEST")
DEFAULT_RATE=$(yq -r '.defaults.sample_rate // "48000"' "$MANIFEST")

encoded=0
skipped=0
missing=0
failed=0

NUM_ARTISTS=$(yq '.artists | length' "$MANIFEST")

for ((a=0; a<NUM_ARTISTS; a++)); do
	ARTIST_SLUG=$(yq -r ".artists[$a].slug" "$MANIFEST")
	NUM_SHOWS=$(yq ".artists[$a].shows | length" "$MANIFEST")

	for ((s=0; s<NUM_SHOWS; s++)); do
		SHOW_SLUG=$(yq -r ".artists[$a].shows[$s].slug" "$MANIFEST")
		NUM_SIDES=$(yq ".artists[$a].shows[$s].sides | length" "$MANIFEST")

		for ((sd=0; sd<NUM_SIDES; sd++)); do
			SIDE_ID=$(yq -r ".artists[$a].shows[$s].sides[$sd].id" "$MANIFEST")
			SOURCE=$(yq -r ".artists[$a].shows[$s].sides[$sd].source" "$MANIFEST")
			BITRATE=$(yq -r ".artists[$a].shows[$s].sides[$sd].bitrate // \"$DEFAULT_BITRATE\"" "$MANIFEST")
			CHANNELS=$(yq -r ".artists[$a].shows[$s].sides[$sd].channels // \"$DEFAULT_CHANNELS\"" "$MANIFEST")
			RATE=$(yq -r ".artists[$a].shows[$s].sides[$sd].sample_rate // \"$DEFAULT_RATE\"" "$MANIFEST")

			SRC_PATH="$RAW_DIR/$SOURCE"
			OUT_NAME="${ARTIST_SLUG}-${SHOW_SLUG}-${SIDE_ID}.opus"
			OUT_PATH="$OUT_DIR/$OUT_NAME"

			if [[ ! -f "$SRC_PATH" ]]; then
				printf '  %-50s SKIP (source not present)\n' "$OUT_NAME"
				missing=$((missing + 1))
				continue
			fi

			if [[ -f "$OUT_PATH" ]]; then
				src_mt=$(stat -c %Y "$SRC_PATH")
				out_mt=$(stat -c %Y "$OUT_PATH")
				if (( out_mt > src_mt )); then
					printf '  %-50s up to date\n' "$OUT_NAME"
					skipped=$((skipped + 1))
					continue
				fi
			fi

			printf '  %-50s encoding ...\n' "$OUT_NAME"

			if ffmpeg \
				-i "$SRC_PATH" \
				-c:a libopus -b:a "$BITRATE" -ac "$CHANNELS" -ar "$RATE" \
				-application audio -vbr on -compression_level 10 \
				-y "$OUT_PATH" \
				-hide_banner -loglevel warning -nostdin </dev/null; then
				size=$(du -h "$OUT_PATH" | cut -f1)
				printf '  %-50s done (%s)\n' "$OUT_NAME" "$size"
				encoded=$((encoded + 1))
			else
				printf '  %-50s FAILED\n' "$OUT_NAME" >&2
				failed=$((failed + 1))
			fi
		done
	done
done

printf '\n%d encoded · %d up-to-date · %d missing sources · %d failed\n' \
	"$encoded" "$skipped" "$missing" "$failed"

if (( failed > 0 )); then
	exit 1
fi