#!/bin/bash
# Rumpk Build Script - Freestanding Doctrine
# Pure Zig L0 + Nim L1, no C stubs, no glibc
#
# We are the standard library now.

set -e

RUMPK_DIR="$(cd "$(dirname "$0")" && pwd)"
BUILD_DIR="$RUMPK_DIR/build"

echo "╔═══════════════════════════════════════╗"
echo "║    RUMPK FREESTANDING BUILD v0.2      ║"
echo "║       No glibc. Pure Sovereignty.     ║"
echo "╚═══════════════════════════════════════╝"
echo ""

# Create build directory
mkdir -p "$BUILD_DIR"
mkdir -p "$BUILD_DIR/nimcache"

# =========================================================
# Step 1: Compile Zig L0 (HAL + Stubs + Context Switch)
# =========================================================
echo "[1/5] Compiling Zig L0 (HAL + libc stubs + context switch)..."

# Compile main.zig
zig build-obj \
    "$RUMPK_DIR/hal/main.zig" \
    -target aarch64-freestanding-none \
    -O ReleaseSmall \
    -femit-bin="$BUILD_DIR/hal.o"

# Compile stubs.zig (our libc replacement)
zig build-obj \
    "$RUMPK_DIR/hal/stubs.zig" \
    -target aarch64-freestanding-none \
    -O ReleaseSmall \
    -femit-bin="$BUILD_DIR/stubs.o"

# Compile switch.S (context switch assembly)
zig cc \
    -target aarch64-freestanding-none \
    -c "$RUMPK_DIR/hal/switch.S" \
    -o "$BUILD_DIR/switch.o"

echo "      → $BUILD_DIR/hal.o"
echo "      → $BUILD_DIR/stubs.o"
echo "      → $BUILD_DIR/switch.o"

# =========================================================
# Step 2: Compile Nim L1 (Kernel + Fibers)
# =========================================================
echo "[2/5] Compiling Nim L1 (Kernel + Fibers)..."

nim c \
    --cpu:arm64 \
    --os:any \
    --mm:arc \
    --noMain:on \
    --cc:clang \
    --passC:"-target aarch64-unknown-none -ffreestanding -fno-stack-protector -fno-builtin" \
    --passL:"-target aarch64-unknown-none -nostdlib -ffreestanding" \
    --define:useMalloc \
    --define:StandaloneHeapSize=65536 \
    -d:release \
    -d:danger \
    --checks:off \
    --assertions:off \
    --boundChecks:off \
    --overflowChecks:off \
    --nimcache:"$BUILD_DIR/nimcache" \
    --path:"$RUMPK_DIR/core" \
    -c \
    "$RUMPK_DIR/core/kernel.nim"

echo "      → $BUILD_DIR/nimcache/*.c"

# =========================================================
# Step 3: Compile Nim C files to objects
# =========================================================
echo "[3/5] Compiling Nim C files..."

for cfile in "$BUILD_DIR/nimcache"/*.c; do
    ofile="${cfile%.c}.o"
    zig cc \
        -target aarch64-freestanding-none \
        -ffreestanding \
        -fno-stack-protector \
        -fno-builtin \
        -fno-sanitize=all \
        -I"$RUMPK_DIR/core/include" \
        -I/usr/lib/nim \
        -I"$RUMPK_DIR/core" \
        -c "$cfile" \
        -o "$ofile" 2>&1 || true
done

echo "      → $BUILD_DIR/nimcache/*.o"

# =========================================================
# Step 4: Link Everything (NO LIBC!)
# =========================================================
echo "[4/5] Linking (freestanding, no libc)..."

# Collect all Nim object files
NIM_OBJS=$(find "$BUILD_DIR/nimcache" -name "*.o" 2>/dev/null | tr '\n' ' ')

if [ -z "$NIM_OBJS" ]; then
    echo "ERROR: No Nim object files found!"
    exit 1
fi

zig cc \
    -target aarch64-freestanding-none \
    -nostdlib \
    -T "$RUMPK_DIR/boot/linker.ld" \
    "$BUILD_DIR/hal.o" \
    "$BUILD_DIR/stubs.o" \
    "$BUILD_DIR/switch.o" \
    $NIM_OBJS \
    -o "$BUILD_DIR/rumpk.elf"

echo "      → $BUILD_DIR/rumpk.elf"

# =========================================================
# Done
# =========================================================
echo ""
echo "✅ Freestanding build complete!"
echo ""
echo "Verification:"
echo "  file $BUILD_DIR/rumpk.elf"
echo ""
echo "Run with:"
echo "  qemu-system-aarch64 -M virt -cpu cortex-a57 -nographic -kernel $BUILD_DIR/rumpk.elf"