#!/bin/sh
# Nomos Turnkey Substrate Installer
# https://sophialabs.ca
# Machine-Enforced Reality for Coding Agents
set -e

# ==============================================================================
# Terminal Aesthetics & Formatting (POSIX Compliant)
# Uses printf command substitution to guarantee escape code evaluation on all shells.
# ==============================================================================
RESET="$(printf '\033[0m')"
BOLD="$(printf '\033[1m')"
CYAN="$(printf '\033[38;2;56;189;248m')"
GREEN="$(printf '\033[38;2;52;211;153m')"
YELLOW="$(printf '\033[38;2;251;191;36m')"
RED="$(printf '\033[38;2;239;68;68m')"

echo ""
echo "${CYAN}${BOLD}  ▲ NOMOS — Deterministic Engineering Substrate${RESET}"
echo "${CYAN}  https://sophialabs.ca | Machine-Enforced Reality for Coding Agents${RESET}"
echo ""

# ==============================================================================
# Phase 1: Operating System & Hardware Architecture Identification
# Matches host environment to pre-compiled static Go binary releases.
# ==============================================================================
OS="$(uname -s | tr '[:upper:]' '[:lower:]')"
ARCH="$(uname -m)"

case "$ARCH" in
    x86_64|amd64)
        ARCH="amd64"
        ;;
    arm64|aarch64)
        ARCH="arm64"
        ;;
    *)
        echo "${RED}❌ Unsupported architecture: $ARCH${RESET}"
        exit 1
        ;;
esac

case "$OS" in
    linux)
        OS="linux"
        ;;
    darwin)
        OS="darwin"
        ;;
    *)
        echo "${RED}❌ Unsupported operating system: $OS${RESET}"
        exit 1
        ;;
esac

echo "${BOLD}🔍 Detected platform:${RESET} ${OS}_${ARCH}"

# ==============================================================================
# Phase 2: Directory Scaffolding & Path Resolution
# Nomos standardizes on ~/.nomos/bin for isolated user-level binary execution.
# ==============================================================================
INSTALL_DIR="$HOME/.nomos/bin"
mkdir -p "$INSTALL_DIR"

BINARY_PATH="$INSTALL_DIR/nomos"
TMP_BIN="$INSTALL_DIR/nomos.tmp.$$"

# ==============================================================================
# Phase 3: Existing Installation Audit
# Alerts user if upgrading an existing local binary in ~/.nomos/bin.
# ==============================================================================
if [ -f "$BINARY_PATH" ]; then
    echo "${YELLOW}⚠️  Existing nomos binary detected at $BINARY_PATH. Upgrading...${RESET}"
fi

# ==============================================================================
# Phase 4: CDN Asset Retrieval
# Directly streams static, symbol-stripped binaries from SophiaLabs.
# Falls back to local Go toolchain if CDN asset is temporarily unreachable.
# ==============================================================================
DOWNLOAD_URL="https://sophialabs.ca/bin/nomos_${OS}_${ARCH}"

echo "⬇️  Downloading pre-compiled Nomos Go binary (${OS}_${ARCH})..."
if curl -fL --progress-bar -o "$TMP_BIN" "$DOWNLOAD_URL" 2>/dev/null || curl -fsSL -o "$TMP_BIN" "$DOWNLOAD_URL"; then
    chmod +x "$TMP_BIN"
    mv "$TMP_BIN" "$BINARY_PATH"
    echo "${GREEN}✓ Downloaded Nomos binary from sophialabs.ca${RESET}"
elif command -v go >/dev/null 2>&1; then
    echo "${YELLOW}ℹ️  CDN asset unavailable. Compiling from Go source via toolchain...${RESET}"
    GOBIN="$INSTALL_DIR" go install github.com/mgantlett/nomos-os/src/nomos@latest
    echo "${GREEN}✓ Compiled and installed via go toolchain.${RESET}"
else
    rm -f "$TMP_BIN"
    echo "${RED}❌ Installation failed. Could not fetch binary from ${DOWNLOAD_URL}.${RESET}"
    echo "   Please check network connectivity or visit https://sophialabs.ca/docs/nomos"
    exit 1
fi

# ==============================================================================
# Phase 5: Post-Installation Smoke Test
# Confirms execution permissions and kernel ABI compatibility on the local host.
# ==============================================================================
if ! "$BINARY_PATH" --help >/dev/null 2>&1; then
    echo "${RED}❌ Installed binary failed smoke test execution on this host.${RESET}"
    exit 1
fi

# ==============================================================================
# Phase 6: Shell Configuration & PATH Synchronization
# Identifies the active shell runtime and safely registers ~/.nomos/bin in PATH.
# ==============================================================================
SHELL_NAME="$(basename "${SHELL:-sh}")"
RC_FILE=""

case "$SHELL_NAME" in
    zsh)
        RC_FILE="$HOME/.zshrc"
        ;;
    bash)
        RC_FILE="$HOME/.bashrc"
        ;;
    *)
        RC_FILE="$HOME/.profile"
        ;;
esac

if ! echo "$PATH" | grep -q "$INSTALL_DIR"; then
    echo ""
    echo "⚙️  Configuring PATH in $RC_FILE..."
    if [ -f "$RC_FILE" ]; then
        if ! grep -q '\.nomos/bin' "$RC_FILE"; then
            printf '\n# Nomos Substrate\nexport PATH="%s:$PATH"\n' "$INSTALL_DIR" >> "$RC_FILE"
            echo "${GREEN}✓ Added $INSTALL_DIR to $RC_FILE${RESET}"
        fi
    else
        printf '# Nomos Substrate\nexport PATH="%s:$PATH"\n' "$INSTALL_DIR" >> "$RC_FILE"
        echo "${GREEN}✓ Created $RC_FILE and configured PATH${RESET}"
    fi
    export PATH="$INSTALL_DIR:$PATH"
fi

# ==============================================================================
# Summary & Agent Onboarding Directives
# Guides human developer to launch their AI agent and execute /nomos-handshake.
# ==============================================================================
echo ""
echo "${GREEN}${BOLD}🎉 Nomos Substrate installed successfully!${RESET}"
echo ""
echo "  Location : ${BINARY_PATH}"
echo "  Protocol : Unified v1.4"
echo ""
echo "${CYAN}${BOLD}🚀 Next Steps:${RESET}"
echo "  1. Reload your shell: ${BOLD}source $RC_FILE${RESET} (or open a new terminal tab)"
echo "  2. Go to any existing git repository: ${BOLD}cd your-project${RESET}"
echo "  3. Open your AI coding agent (Cursor, Claude Code, Antigravity) and type:"
echo "     ${CYAN}${BOLD}/nomos-handshake${RESET}"
echo ""
echo "  💡 To uninstall anytime: ${BOLD}curl -fsSL https://sophialabs.ca/uninstall | sh${RESET}"
echo ""