#!/bin/sh
# AgentSpan installer — installs the CLI binary and Java 21+ (required for the server).
# SDK install is language-specific: pip install agentspan / npm install @agentspan-ai/sdk
# Usage: curl -fsSL https://raw.githubusercontent.com/agentspan-ai/agentspan/main/cli/install.sh | sh
set -e

S3_BUCKET="https://agentspan.s3.us-east-2.amazonaws.com"
BINARY_NAME="agentspan"
INSTALL_DIR="${INSTALL_DIR:-/usr/local/bin}"
JAVA_MIN=21

ADOPTIUM_URL="https://adoptium.net/temurin/releases/?version=${JAVA_MIN}"

# ── Colors ────────────────────────────────────────────────────────────────────
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
CYAN='\033[0;36m'
BOLD='\033[1m'
NC='\033[0m'

step() { printf "\n${CYAN}${BOLD}[%s/4]${NC} %s\n" "$1" "$2"; }
ok()   { printf "  ${GREEN}✓${NC} %s\n" "$1"; }
warn() { printf "  ${YELLOW}!${NC} %s\n" "$1"; }
info() { printf "       %s\n" "$1"; }
die()  { printf "\n${RED}Error:${NC} %s\n" "$1" >&2; exit 1; }

# ── Prompt helper ─────────────────────────────────────────────────────────────
# Works even when the script is piped through `curl | sh` by reading from /dev/tty.
prompt_yn() {
    printf "  ${YELLOW}?${NC} %s [y/N] " "$1"
    read -r answer </dev/tty 2>/dev/null || answer="n"
    case "$answer" in
        [Yy]|[Yy][Ee][Ss]) return 0 ;;
        *) return 1 ;;
    esac
}

# ── Cleanup on unexpected exit ────────────────────────────────────────────────
TMP_DIR=""
cleanup() { [ -n "$TMP_DIR" ] && rm -rf "$TMP_DIR"; }
trap cleanup EXIT INT TERM

# ── Step 1: Detect platform ───────────────────────────────────────────────────
step 1 "Detecting platform..."

detect_os() {
    OS="$(uname -s)"
    case "$OS" in
        Linux*)               OS='linux';;
        Darwin*)              OS='darwin';;
        CYGWIN*|MINGW*|MSYS*) OS='windows';;
        *) die "Unsupported operating system: $OS";;
    esac
}

detect_arch() {
    ARCH="$(uname -m)"
    case "$ARCH" in
        x86_64|amd64)  ARCH='amd64';;
        arm64|aarch64) ARCH='arm64';;
        armv7l|armv6l) die "32-bit ARM (${ARCH}) is not supported. Binaries require arm64 or amd64.";;
        *) die "Unsupported architecture: $ARCH. See https://docs.agentspan.dev for manual install.";;
    esac
}

detect_os
detect_arch
ok "Platform: ${OS}/${ARCH}"

# Detect Linux package manager
PKG_MGR=""
if [ "$OS" = "linux" ]; then
    if   command -v apt-get >/dev/null 2>&1; then PKG_MGR="apt"
    elif command -v dnf     >/dev/null 2>&1; then PKG_MGR="dnf"
    elif command -v yum     >/dev/null 2>&1; then PKG_MGR="yum"
    elif command -v pacman  >/dev/null 2>&1; then PKG_MGR="pacman"
    fi
fi

# ── Step 2: Check + install Java 21+ ─────────────────────────────────────────
step 2 "Checking Java ${JAVA_MIN}+..."

# Helper: check a specific java binary's version
check_java_bin() {
    _bin="$1"
    [ -z "$_bin" ] && return 1
    command -v "$_bin" >/dev/null 2>&1 || [ -x "$_bin" ] || return 1
    _ver=$("$_bin" -version 2>&1 | head -1 | sed 's/.*"\(.*\)".*/\1/' | cut -d. -f1)
    # Old 1.x versioning (Java 8 reports "1.8")
    [ "$_ver" = "1" ] && _ver=$("$_bin" -version 2>&1 | head -1 | sed 's/.*"\(.*\)".*/\1/' | cut -d. -f2)
    if [ "$_ver" -ge "$JAVA_MIN" ] 2>/dev/null; then
        ok "Java $_ver found"
        JAVA_OK=true
        return 0
    fi
    return 1
}

JAVA_OK=false

# Search order: JAVA_HOME → sdkman → asdf → PATH
# Covers users whose version manager doesn't activate in non-interactive shells
# (which is what `curl | sh` runs as).
for _java_candidate in \
    "${JAVA_HOME:+$JAVA_HOME/bin/java}" \
    "$HOME/.sdkman/candidates/java/current/bin/java" \
    "$HOME/.asdf/shims/java" \
    "java"; do
    [ -z "$_java_candidate" ] && continue
    check_java_bin "$_java_candidate" && break
done

# Also try jenv if available
if [ "$JAVA_OK" = false ] && command -v jenv >/dev/null 2>&1; then
    _jenv_java="$(jenv which java 2>/dev/null)" || true
    [ -n "$_jenv_java" ] && check_java_bin "$_jenv_java" || true
fi

if [ "$JAVA_OK" = false ]; then
    warn "Java ${JAVA_MIN}+ not found. It is required to run the AgentSpan server."
    if prompt_yn "Install Java ${JAVA_MIN} (Eclipse Temurin) now?"; then
        JAVA_INSTALLED=false

        if [ "$OS" = "darwin" ] && command -v brew >/dev/null 2>&1; then
            info "Running: brew install --cask temurin@${JAVA_MIN}"
            brew install --cask "temurin@${JAVA_MIN}" && JAVA_INSTALLED=true

        elif [ "$OS" = "linux" ]; then
            case "$PKG_MGR" in
                apt)
                    info "Adding Eclipse Temurin apt repository..."
                    sudo apt-get install -y wget apt-transport-https gnupg 2>/dev/null
                    sudo mkdir -p /etc/apt/keyrings
                    wget -qO - https://packages.adoptium.net/artifactory/api/gpg/key/public \
                        | sudo tee /etc/apt/keyrings/adoptium.asc >/dev/null
                    printf "deb [signed-by=/etc/apt/keyrings/adoptium.asc] https://packages.adoptium.net/artifactory/deb $(. /etc/os-release && echo "$VERSION_CODENAME") main\n" \
                        | sudo tee /etc/apt/sources.list.d/adoptium.list >/dev/null
                    sudo apt-get update -q
                    sudo apt-get install -y "temurin-${JAVA_MIN}-jdk" && JAVA_INSTALLED=true
                    ;;
                dnf|yum)
                    info "Adding Eclipse Temurin RPM repository..."
                    cat <<EOF | sudo tee /etc/yum.repos.d/adoptium.repo >/dev/null
[Adoptium]
name=Adoptium
baseurl=https://packages.adoptium.net/artifactory/rpm/\$releasever/\$basearch
enabled=1
gpgcheck=1
gpgkey=https://packages.adoptium.net/artifactory/api/gpg/key/public
EOF
                    sudo "$PKG_MGR" install -y "temurin-${JAVA_MIN}-jdk" && JAVA_INSTALLED=true
                    ;;
                pacman)
                    if command -v yay >/dev/null 2>&1; then
                        yay -S --noconfirm "jdk${JAVA_MIN}-temurin" && JAVA_INSTALLED=true
                    else
                        warn "yay not found. Install Java manually: $ADOPTIUM_URL"
                    fi
                    ;;
                *)
                    warn "Unknown package manager. Install Java ${JAVA_MIN}+ manually:"
                    warn "  $ADOPTIUM_URL"
                    ;;
            esac
        else
            warn "Automatic Java install not supported on this platform."
            warn "Download Java ${JAVA_MIN} from: $ADOPTIUM_URL"
        fi

        if [ "$JAVA_INSTALLED" = true ]; then
            ok "Java ${JAVA_MIN} installed"
        else
            warn "Java install did not complete. Install manually before running 'agentspan server start':"
            warn "  $ADOPTIUM_URL"
        fi
    else
        warn "Skipping Java install. You will need Java ${JAVA_MIN}+ to run 'agentspan server start'."
        warn "  $ADOPTIUM_URL"
    fi
fi

# ── curl / wget ───────────────────────────────────────────────────────────────
if command -v curl >/dev/null 2>&1; then
    DOWNLOADER="curl"
elif command -v wget >/dev/null 2>&1; then
    DOWNLOADER="wget"
else
    die "Neither curl nor wget found. Please install one and re-run."
fi

# ── Step 3: Download CLI binary + verify checksum ─────────────────────────────
step 3 "Downloading CLI binary..."

BINARY_FILENAME="${BINARY_NAME}_${OS}_${ARCH}"
if [ "$OS" = "windows" ]; then
    BINARY_FILENAME="${BINARY_FILENAME}.exe"
    BINARY_NAME="${BINARY_NAME}.exe"
fi

DOWNLOAD_URL="${S3_BUCKET}/cli/latest/${BINARY_FILENAME}"
CHECKSUM_URL="${S3_BUCKET}/cli/latest/${BINARY_FILENAME}.sha256"
VERSION_URL="${S3_BUCKET}/cli/latest/version.txt"

TMP_DIR=$(mktemp -d)
TMP_FILE="$TMP_DIR/$BINARY_NAME"
TMP_CHECKSUM="$TMP_DIR/${BINARY_FILENAME}.sha256"

download() {
    url="$1"; dest="$2"
    if [ "$DOWNLOADER" = "curl" ]; then
        curl -fsSL --progress-bar "$url" -o "$dest"
    else
        wget -q --show-progress "$url" -O "$dest"
    fi
}

# Skip download if already on latest version
CLI_SKIP=false
if command -v agentspan >/dev/null 2>&1; then
    CURRENT_VER=$(agentspan version 2>/dev/null | awk '{print $2}') || CURRENT_VER=""
    if [ -n "$CURRENT_VER" ] && download "$VERSION_URL" "$TMP_DIR/version.txt" 2>/dev/null; then
        LATEST_VER=$(tr -d '[:space:]' < "$TMP_DIR/version.txt")
        if [ "$CURRENT_VER" = "$LATEST_VER" ]; then
            ok "CLI already up to date ($CURRENT_VER) — skipping download"
            CLI_SKIP=true
        else
            info "Upgrading CLI: $CURRENT_VER → $LATEST_VER"
        fi
    fi
fi

if [ "$CLI_SKIP" = false ]; then
    info "From: $DOWNLOAD_URL"
    download "$DOWNLOAD_URL" "$TMP_FILE" || die "Failed to download binary."

    # Verify checksum
    if download "$CHECKSUM_URL" "$TMP_CHECKSUM" 2>/dev/null; then
        EXPECTED=$(tr -d '[:space:]' < "$TMP_CHECKSUM")
        if [ -n "$EXPECTED" ]; then
            if   command -v sha256sum >/dev/null 2>&1; then ACTUAL=$(sha256sum "$TMP_FILE" | awk '{print $1}')
            elif command -v shasum    >/dev/null 2>&1; then ACTUAL=$(shasum -a 256 "$TMP_FILE" | awk '{print $1}')
            else warn "sha256sum/shasum not available — skipping checksum verification."; ACTUAL=""
            fi
            if [ -n "$ACTUAL" ]; then
                if [ "$ACTUAL" = "$EXPECTED" ]; then
                    ok "Checksum verified (SHA256: $(printf '%.16s' "$ACTUAL")...)"
                else
                    die "Checksum mismatch!\n  Expected: $EXPECTED\n  Got:      $ACTUAL\nDownload may be corrupted. Please try again."
                fi
            fi
        fi
    else
        warn "Checksum file not available — skipping signature verification."
    fi

    chmod +x "$TMP_FILE"

    if [ -w "$INSTALL_DIR" ]; then
        mv "$TMP_FILE" "$INSTALL_DIR/$BINARY_NAME"
        ok "Installed to $INSTALL_DIR/$BINARY_NAME"
    else
        warn "$INSTALL_DIR is not writable — trying sudo..."
        sudo mv "$TMP_FILE" "$INSTALL_DIR/$BINARY_NAME" \
            || die "Could not install to $INSTALL_DIR. Re-run with INSTALL_DIR=~/bin or as root."
        ok "Installed to $INSTALL_DIR/$BINARY_NAME (via sudo)"
    fi
fi

# ── PATH ──────────────────────────────────────────────────────────────────────
if ! command -v agentspan >/dev/null 2>&1; then
    warn "agentspan not found in PATH."
    SHELL_NAME=$(basename "${SHELL:-sh}")
    case "$SHELL_NAME" in
        zsh)  PROFILE="$HOME/.zshrc" ;;
        bash) if [ -f "$HOME/.bashrc" ]; then PROFILE="$HOME/.bashrc"
              else PROFILE="$HOME/.bash_profile"; fi ;;
        fish) PROFILE="$HOME/.config/fish/config.fish" ;;
        *)    PROFILE="" ;;
    esac
    if [ -n "$PROFILE" ] && prompt_yn "Add $INSTALL_DIR to PATH in $PROFILE?"; then
        printf '\nexport PATH="%s:$PATH"\n' "$INSTALL_DIR" >> "$PROFILE"
        ok "Added to $PROFILE"
        warn "Run this now or restart your terminal: export PATH=\"$INSTALL_DIR:\$PATH\""
    else
        warn "Add manually: export PATH=\"$INSTALL_DIR:\$PATH\""
    fi
fi

# ── Step 4: Verify with agentspan doctor ──────────────────────────────────────
step 4 "Running agentspan doctor..."

if command -v agentspan >/dev/null 2>&1; then
    printf "\n"
    agentspan doctor || warn "agentspan doctor reported issues — see above."
else
    warn "agentspan not in PATH yet — skipping doctor."
    warn "Run 'agentspan doctor' after restarting your terminal."
fi

# ── Done ──────────────────────────────────────────────────────────────────────
printf "\n${GREEN}${BOLD}AgentSpan CLI is ready.${NC}\n"
printf "\nNext steps:\n"
printf "  1. Install your SDK:\n"
printf "       Python:     pip install agentspan\n"
printf "       TypeScript: npm install @agentspan-ai/sdk\n"
printf "       Java:       see https://docs.agentspan.dev/sdk/java\n"
printf "  2. Set your LLM API key:   export OPENAI_API_KEY=sk-...\n"
printf "  3. Start the server:       agentspan server start\n"
printf "  4. Open the UI:            http://localhost:6767\n"
printf "\nDocs: https://docs.agentspan.dev\n\n"