Initial commit: akai-fetch - AKAI sampler ISO downloader & extractor

- fetch: Go CLI tool for searching, downloading, and extracting
  AKAI sampler ISOs from archive.org
- scripts/extract_wavs.sh: Shell script driving akaiutil to
  convert samples to WAV
- Dockerfile: Multi-stage build packaging akaiutil + fetch
- third_party/akaiutil: Vendored akaiutil v4.6.7 source (GPLv2)
- docs/akaiutil.md: Full akaiutil reference

scripts/extract_wavs.sh

@@ -0,0 +1,115 @@
+#!/usr/bin/env bash
+# Extract all AKAI samples as WAV from all volumes in an AKAI disk image.
+# Usage: ./extract_wavs.sh <iso-file> [output-dir]
+# Uses a single akaiutil session to avoid repeated disk rescans.
+
+set -euo pipefail
+
+AKAIUTIL="${AKAIUTIL:-akaiutil}"
+ISO="${1:?Usage: $0 <iso-file> [output-dir]}"
+OUTPUT="${2:-wavs}"
+
+# Derive ISO basename without extension, sanitized for filesystem use
+isobase=$(basename "$ISO")
+isobase="${isobase%.*}"
+isobase=$(echo "$isobase" | sed 's/ /_/g' | sed 's/[^A-Za-z0-9_.-]/_/g' | sed 's/__*/_/g' | sed 's/^[_.]//; s/[_.]$//')
+OUTPUT="$OUTPUT/$isobase"
+
+TMPFILE=$(mktemp /tmp/akai_cmds.XXXXXX)
+trap 'rm -f "$TMPFILE"' EXIT
+
+mkdir -p "$OUTPUT"
+
+# Phase 1: enumerate partitions from df output
+echo "Enumerating partitions and volumes..."
+DF_OUTPUT=$("$AKAIUTIL" -r "$ISO" 2>/dev/null <<< $'df\nq')
+
+# Parse partition letters from the partition table in df output
+PARTITIONS=()
+while IFS= read -r line; do
+  if [[ "$line" =~ ^[[:space:]]+([A-Z])[[:space:]]+ ]]; then
+    PARTITIONS+=("${BASH_REMATCH[1]}")
+  fi
+done <<< "$DF_OUTPUT"
+
+if [[ ${#PARTITIONS[@]} -eq 0 ]]; then
+  echo "No partitions found in ISO. Trying single-partition layout..."
+  PARTITIONS=("A")
+fi
+
+echo "Found partitions: ${PARTITIONS[*]}"
+
+# Scan each partition for volumes
+VOLUME_LIST=$(
+  {
+    for p in "${PARTITIONS[@]}"; do
+      echo "cd /disk0/$p"
+      echo "dir"
+    done
+    echo "q"
+  } | "$AKAIUTIL" -r "$ISO" 2>/dev/null
+)
+
+# Parse partition-letter:volume-name pairs
+VOLUMES=()
+CURRENT_PART=""
+while IFS= read -r line; do
+  for p in "${PARTITIONS[@]}"; do
+    if [[ "$line" == *"/disk0/$p >"* ]]; then
+      CURRENT_PART="$p"
+    fi
+  done
+  if [[ "$line" =~ ^[[:space:]]+[0-9]+[[:space:]]+(.+)[[:space:]]+-[[:space:]]+ ]]; then
+    name="${BASH_REMATCH[1]}"
+    name="${name%%  -*}"
+    name="$(echo "$name" | sed 's/  *$//')"
+    if [[ -n "$CURRENT_PART" && -n "$name" ]]; then
+      VOLUMES+=("$CURRENT_PART|$name")
+    fi
+  fi
+done <<< "$VOLUME_LIST"
+
+echo "Found ${#VOLUMES[@]} volumes"
+
+# Phase 2: build command file and create output dirs
+> "$TMPFILE"
+
+for entry in "${VOLUMES[@]}"; do
+  IFS='|' read -r part vol_name <<< "$entry"
+
+  safe_name=$(echo "$vol_name" | sed 's/ /_/g' | sed 's/[^A-Za-z0-9_.-]/_/g' | sed 's/__*/_/g' | sed 's/^[_.]//; s/[_.]$//')
+  [[ -z "$safe_name" ]] && safe_name="volume"
+
+  vol_dir="$OUTPUT/$safe_name"
+  mkdir -p "$vol_dir"
+
+  nav_name="${vol_name// /_}"
+  echo "lcd $vol_dir" >> "$TMPFILE"
+  echo "cd /disk0/$part/$nav_name" >> "$TMPFILE"
+  echo "sample2wavall" >> "$TMPFILE"
+done
+
+echo "lcd /" >> "$TMPFILE"
+echo "q" >> "$TMPFILE"
+
+# Phase 3: run extraction
+echo "Starting extraction..."
+START=$SECONDS
+"$AKAIUTIL" -r "$ISO" < "$TMPFILE" 2>/dev/null > /tmp/akai_output.txt
+DURATION=$((SECONDS - START))
+
+total=0
+while IFS= read -r line; do
+  if [[ "$line" =~ exported[[:space:]]+([0-9]+)[[:space:]]+file ]]; then
+    count="${BASH_REMATCH[1]}"
+    total=$((total + count))
+    echo "  -> $count WAVs"
+  fi
+done < /tmp/akai_output.txt
+
+echo ""
+echo "--- Done in ${DURATION}s ---"
+echo "Total WAV files: $total"
+
+echo ""
+echo "WAVs are in: $OUTPUT/"