#!/bin/sh
set -e

ALPINE_ROOT="/build/initramfs"
COMPONENTS_DIR="/build/components"
CACHE_DIR="/build/cache/source"

echo "[+] Compiling Zero-OS components from git submodules..."

# Create build directories
mkdir -p "$CACHE_DIR"

# Check if submodules are available
if [ ! -d "$COMPONENTS_DIR" ]; then
    echo "Error: Components directory not found. Run setup-submodules.sh first."
    exit 1
fi

# Function to prepare component for building
prepare_component() {
    local component_name="$1"
    local component_dir="$COMPONENTS_DIR/$component_name"
    
    if [ ! -d "$component_dir" ]; then
        echo "    Warning: $component_name submodule not found at $component_dir"
        return 1
    fi
    
    echo "    Preparing $component_name..."
    cd "$component_dir"
    
    # Update submodule if needed
    if [ -d ".git" ]; then
        git pull origin main 2>/dev/null || git pull origin master 2>/dev/null || echo "    Using existing checkout"
    fi
    
    return 0
}

# Function to build Rust project from submodule
build_rust_component() {
    local component_name="$1"
    local binary_name="$2"
    local install_path="$3"
    
    echo "  Building Rust component: $component_name"
    
    if ! prepare_component "$component_name"; then
        echo "    Skipping $component_name (not available)"
        return 1
    fi
    
    # Build the project
    echo "    Compiling with cargo for musl target..."
    
    # Source cargo environment
    . ~/.cargo/env
    
    # Set git version for components that use git_version macro
    export GIT_DESCRIBE=$(cd "$COMPONENTS_DIR/$component_name" && git describe --tags --always --dirty=-modified 2>/dev/null || echo "unknown")
    
    # Build with musl target for static linking
    cargo build --release --target x86_64-unknown-linux-musl
    
    # Install binary to Alpine root
    mkdir -p "$ALPINE_ROOT$install_path"
    cp "target/x86_64-unknown-linux-musl/release/$binary_name" "$ALPINE_ROOT$install_path/"
    chmod +x "$ALPINE_ROOT$install_path/$binary_name"
    
    echo "    Success: $install_path/$binary_name installed to Alpine root (musl static)"
    return 0
}

# Function to build Go project from submodule
build_go_component() {
    local component_name="$1"
    local binary_name="$2"
    local install_path="$3"
    local build_cmd="$4"
    
    echo "  Building Go component: $component_name"
    
    if ! prepare_component "$component_name"; then
        echo "    Skipping $component_name (not available)"
        return 1
    fi
    
    # Build the project
    echo "    Compiling with go..."
    if command -v go >/dev/null; then
        if [ -n "$build_cmd" ]; then
            eval "$build_cmd"
        else
            go build -o "$binary_name"
        fi
        
        # Install binary to Alpine root
        mkdir -p "$ALPINE_ROOT$install_path"
        cp "$binary_name" "$ALPINE_ROOT$install_path/"
        chmod +x "$ALPINE_ROOT$install_path/$binary_name"
        
        echo "    Success: $install_path/$binary_name installed to Alpine root"
        return 0
    else
        echo "    Error: go not found - installing Go..."
        apk add --no-cache go
        if [ -n "$build_cmd" ]; then
            eval "$build_cmd"
        else
            go build -o "$binary_name"
        fi
        
        mkdir -p "$ALPINE_ROOT$install_path"
        cp "$binary_name" "$ALPINE_ROOT$install_path/"
        chmod +x "$ALPINE_ROOT$install_path/$binary_name"
        
        echo "    Success: $install_path/$binary_name installed to Alpine root"
        return 0
    fi
}

# Install build dependencies if needed
echo "  Checking build dependencies..."
if ! command -v git >/dev/null; then
    echo "    Installing git..."
    apk add --no-cache git
fi

echo ""

# Ensure Alpine root directory exists
if [ ! -d "$ALPINE_ROOT" ]; then
    echo "Creating Alpine initramfs root at $ALPINE_ROOT"
    mkdir -p "$ALPINE_ROOT"
fi

# Build each Zero-OS component from submodules
echo "Building Zero-OS components from submodules:"

# 1. Zinit - Init system (Rust) - master branch
if build_rust_component "zinit" "zinit" "/sbin"; then
    echo "    Zinit built successfully"
else
    echo "    Warning: Failed to build zinit"
fi

# 2. RFS - Rust filesystem (Rust) - v2.0.6 with musl
if build_rust_component "rfs" "rfs" "/usr/bin"; then
    echo "    RFS built successfully"
else
    echo "    Warning: Failed to build rfs"
fi

# 3. CoreX - Container control (static binary) - v2.1.4
echo "  Installing CoreX static binary..."
if [ -f "$COMPONENTS_DIR/corex/corex" ]; then
    mkdir -p "$ALPINE_ROOT/usr/bin"
    cp "$COMPONENTS_DIR/corex/corex" "$ALPINE_ROOT/usr/bin/"
    chmod +x "$ALPINE_ROOT/usr/bin/corex"
    echo "    CoreX installed successfully"
else
    echo "    Warning: CoreX binary not found"
fi

# 4. Mycelium - Networking layer (Rust) - 0.6.1 with musl
if build_rust_component "mycelium" "mycelium" "/usr/bin"; then
    echo "    Mycelium built successfully"
else
    echo "    Warning: Failed to build mycelium"
fi

echo ""
echo "[+] Zero-OS component compilation completed"

# Show installed binaries info
echo ""
echo "[+] Compiled Zero-OS components in Alpine root:"
for binary in "/sbin/zinit" "/usr/bin/rfs" "/usr/bin/corex" "/usr/bin/mycelium"; do
    if [ -x "$ALPINE_ROOT$binary" ]; then
        size=$(stat -c%s "$ALPINE_ROOT$binary" 2>/dev/null || echo "unknown")
        echo "  $binary (${size} bytes)"
    else
        echo "  $binary (NOT BUILT)"
    fi
done

echo "[+] Zero-OS binaries installed to Alpine root filesystem"