#!/usr/bin/env bash
# NexusOS WSL bootstrap — called by install-windows.ps1 after the repo is copied in.
# Safe to re-run; skips steps that are already done.

set -euo pipefail

NEXUS_ROOT="$(cd "$(dirname "$0")/.." && pwd)"
cd "$NEXUS_ROOT"

step()  { echo ""; echo "==> $*"; }
ok()    { echo "    ok:   $*"; }
warn()  { echo "    warn: $*"; }

# ── System packages ───────────────────────────────────────────────────────────

step "System packages"
sudo apt-get update -qq
sudo apt-get install -y -qq \
    python3 python3-venv python3-pip python3-tk \
    curl wget git build-essential \
    libsqlite3-dev rsync
ok "System packages ready"

# ── Node.js (via NodeSource LTS) ──────────────────────────────────────────────

step "Node.js"
if command -v node &>/dev/null; then
    ok "Already installed: $(node --version)"
else
    curl -fsSL https://deb.nodesource.com/setup_lts.x | sudo -E bash - 2>/dev/null
    sudo apt-get install -y -qq nodejs
    ok "Installed: $(node --version)"
fi

# ── Python venv ───────────────────────────────────────────────────────────────

step "Python venv (Promethean)"
if [ ! -d "$NEXUS_ROOT/Promethean" ]; then
    python3 -m venv "$NEXUS_ROOT/Promethean"
    ok "Created"
else
    ok "Already exists"
fi

source "$NEXUS_ROOT/Promethean/bin/activate"
pip install --upgrade pip -q

step "Python dependencies"
pip install -r "$NEXUS_ROOT/requirements-wsl.txt" -q
ok "Installed"

# ── Ollama ────────────────────────────────────────────────────────────────────

step "Ollama"
mkdir -p "$NEXUS_ROOT/runtime/logs"
OLLAMA_BIN="$NEXUS_ROOT/ollama/bin/ollama"
DEFAULT_MODEL="${NEXUS_DEFAULT_MODEL:-qwen2.5:3b}"

case "$(uname -m)" in
    x86_64|amd64) ;;
    *)
        echo "ERROR: bundled Ollama supports x86-64 WSL only (detected $(uname -m))." >&2
        exit 1
        ;;
esac

if [ ! -x "$OLLAMA_BIN" ]; then
    chmod +x "$OLLAMA_BIN" 2>/dev/null || true
fi
if [ ! -x "$OLLAMA_BIN" ] || ! "$OLLAMA_BIN" --version &>/dev/null; then
    echo "ERROR: bundled Ollama could not run in this WSL distro." >&2
    echo "       Expected a Linux x86-64 executable at: $OLLAMA_BIN" >&2
    exit 1
fi
ok "Binary OK: $("$OLLAMA_BIN" --version)"

# A clean checkout has no model files. Provision one so the first launch can chat.
OLLAMA_HOST="127.0.0.1:11434"
OLLAMA_MODELS="$NEXUS_ROOT/models"
OLLAMA_HOST="$OLLAMA_HOST" OLLAMA_MODELS="$OLLAMA_MODELS" \
    "$OLLAMA_BIN" list 2>/dev/null | awk -v model="$DEFAULT_MODEL" \
    'NR > 1 && $1 == model { found = 1 } END { exit !found }' \
    || {
        ollama_pid=""
        if ! curl -fsS "http://127.0.0.1:11434/api/tags" >/dev/null 2>&1; then
            OLLAMA_HOST="$OLLAMA_HOST" OLLAMA_MODELS="$NEXUS_ROOT/models" \
                "$OLLAMA_BIN" serve >>"$NEXUS_ROOT/runtime/logs/ollama.log" 2>&1 &
            ollama_pid=$!
            for _ in {1..30}; do
                curl -fsS "http://127.0.0.1:11434/api/tags" >/dev/null 2>&1 && break
                sleep 1
            done
        fi

        if ! curl -fsS "http://127.0.0.1:11434/api/tags" >/dev/null 2>&1; then
            [ -n "$ollama_pid" ] && kill "$ollama_pid" 2>/dev/null || true
            echo "ERROR: Ollama did not start; see runtime/logs/ollama.log" >&2
            exit 1
        fi

        if ! OLLAMA_HOST="$OLLAMA_HOST" OLLAMA_MODELS="$OLLAMA_MODELS" \
            "$OLLAMA_BIN" list 2>/dev/null | awk -v model="$DEFAULT_MODEL" \
            'NR > 1 && $1 == model { found = 1 } END { exit !found }'; then
            echo "    pulling default model: $DEFAULT_MODEL"
            if ! OLLAMA_HOST="$OLLAMA_HOST" OLLAMA_MODELS="$OLLAMA_MODELS" \
                "$OLLAMA_BIN" pull "$DEFAULT_MODEL"; then
                [ -n "$ollama_pid" ] && kill "$ollama_pid" 2>/dev/null || true
                echo "ERROR: Could not pull default model $DEFAULT_MODEL." >&2
                exit 1
            fi
        fi
        [ -n "$ollama_pid" ] && kill "$ollama_pid" 2>/dev/null || true
        ok "Model ready: $DEFAULT_MODEL"
    }

# ── Frontend npm deps ─────────────────────────────────────────────────────────

step "Frontend dependencies"
cd "$NEXUS_ROOT/interface/web"
npm install --silent
ok "Installed"
cd "$NEXUS_ROOT"

# ── Runtime dirs ─────────────────────────────────────────────────────────────

step "Runtime directories"
mkdir -p "$NEXUS_ROOT/runtime/pids" "$NEXUS_ROOT/runtime/logs"
ok "Ready"

# ── Shell alias (ncp) ─────────────────────────────────────────────────────────

step "Shell alias"
if ! grep -q "nexus-core/management/nexus-cli.sh" "$HOME/.bashrc" 2>/dev/null; then
    cat >> "$HOME/.bashrc" << 'EOF'

# NexusOS
ncp() { ~/nexus-core/management/nexus-cli.sh "$@"; }
EOF
    ok "ncp alias added to ~/.bashrc"
else
    ok "ncp already in ~/.bashrc"
fi

step "Promethean command"
PROMETHEAN_RC="$NEXUS_ROOT/.promethean_bashrc"
if [ ! -f "$PROMETHEAN_RC" ]; then
    cat > "$PROMETHEAN_RC" << 'EOF'
# Promethean Terminal shell init
[[ -f ~/.bashrc ]] && source ~/.bashrc
export VIRTUAL_ENV_DISABLE_PROMPT=1
if [[ -f "$HOME/nexus-core/Promethean/bin/activate" ]]; then
    source "$HOME/nexus-core/Promethean/bin/activate"
fi
export PS1='\[\e[0;35m\](Promethean)\[\e[0m\] ${debian_chroot:+($debian_chroot)}\[\e[0;37m\]\u@\h\[\e[0m\]:\[\e[1;32m\]\w\[\e[0m\]\$ '
printf '\e]0;Promethean Terminal\a'
EOF
    ok "Promethean environment init created"
else
    ok "Promethean environment init already exists"
fi
if ! grep -qF "alias promethean='source ~/nexus-core/.promethean_bashrc'" "$HOME/.bashrc" 2>/dev/null; then
    cat >> "$HOME/.bashrc" << 'EOF'

# Promethean
alias promethean='source ~/nexus-core/.promethean_bashrc'
EOF
    ok "promethean command added to ~/.bashrc"
else
    ok "promethean command already in ~/.bashrc"
fi

# ── Windows Terminal profile + desktop shortcut ───────────────────────────────

setup_windows() {
    local win_user distro icon_src icon_win_dir icon_win_path

    win_user=$(powershell.exe -command '$env:USERNAME' 2>/dev/null | tr -d '\r\n')
    distro="${WSL_DISTRO_NAME:-$(uname -n)}"

    if [ -z "$win_user" ] || [ ! -d "/mnt/c/Users/$win_user" ]; then
        warn "Cannot locate Windows user directory — skipping Windows Terminal setup"
        return 0
    fi

    # Copy app icon into Windows filesystem so WT can display it
    icon_src="$NEXUS_ROOT/assets/n-small.png"
    icon_win_dir="/mnt/c/Users/$win_user/AppData/Local/NexusOS"
    mkdir -p "$icon_win_dir"
    [ -f "$icon_src" ] && cp "$icon_src" "$icon_win_dir/nexus.png"
    icon_win_path="C:\\Users\\$win_user\\AppData\\Local\\NexusOS\\nexus.png"

    # Init file so the WT session sources nvm + ncp
    cat > "$HOME/.nexus_init" << 'EOF'
[[ -f ~/.bashrc ]] && source ~/.bashrc
EOF

    # Patch Windows Terminal settings.json via Python (handles JSONC safely)
    python3 - "$win_user" "$distro" "$icon_win_path" << 'PYEOF'
    import json, re, uuid, sys
from pathlib import Path

win_user, distro, icon_path = sys.argv[1], sys.argv[2], sys.argv[3]

candidates = [
    f"/mnt/c/Users/{win_user}/AppData/Local/Packages/Microsoft.WindowsTerminal_8wekyb3d8bbwe/LocalState/settings.json",
    f"/mnt/c/Users/{win_user}/AppData/Local/Packages/Microsoft.WindowsTerminalPreview_8wekyb3d8bbwe/LocalState/settings.json",
]

settings_path = next((Path(p) for p in candidates if Path(p).exists()), None)
if not settings_path:
    print("    warn: Windows Terminal not found — skipping profile")
    sys.exit(0)

def strip_jsonc(text):
    output = []
    in_string = False
    escaped = False
    in_line_comment = False
    in_block_comment = False
    index = 0
    while index < len(text):
        char = text[index]
        next_char = text[index + 1] if index + 1 < len(text) else ""
        if in_line_comment:
            if char == "\n":
                in_line_comment = False
                output.append(char)
        elif in_block_comment:
            if char == "*" and next_char == "/":
                in_block_comment = False
                index += 1
        elif in_string:
            output.append(char)
            if escaped:
                escaped = False
            elif char == "\\":
                escaped = True
            elif char == '"':
                in_string = False
        elif char == '"':
            in_string = True
            output.append(char)
        elif char == "/" and next_char == "/":
            in_line_comment = True
            index += 1
        elif char == "/" and next_char == "*":
            in_block_comment = True
            index += 1
        else:
            output.append(char)
        index += 1
    return "".join(output)

try:
    with open(settings_path, encoding="utf-8") as f:
        settings_text = strip_jsonc(f.read())
        settings = json.loads(re.sub(r",(\s*[}\]])", r"\1", settings_text))
except (OSError, json.JSONDecodeError) as error:
    print(f"    warn: Could not read Windows Terminal settings: {error}")
    sys.exit(0)

profiles = settings.setdefault("profiles", {}).setdefault("list", [])
if any(p.get("name") == "NexusOS" for p in profiles):
    print("    ok:   NexusOS profile already in Windows Terminal")
    sys.exit(0)

profiles.insert(0, {
    "guid": "{" + str(uuid.uuid4()) + "}",
    "name": "NexusOS",
    "commandline": f"wsl.exe -d {distro} bash --init-file ~/.nexus_init",
    "startingDirectory": "~",
    "icon": icon_path,
})

try:
    with open(settings_path, "w", encoding="utf-8") as f:
        json.dump(settings, f, indent=4)
except OSError as error:
    print(f"    warn: Could not update Windows Terminal settings: {error}")
    sys.exit(0)

print(f"    ok:   NexusOS profile added to Windows Terminal")
PYEOF

    # Desktop shortcut — opens WT to the NexusOS profile and launches Nexus
    powershell.exe -command "
\$ws = New-Object -ComObject WScript.Shell
\$s = \$ws.CreateShortcut(\"\$env:USERPROFILE\Desktop\NexusOS.lnk\")
\$s.TargetPath = 'wt.exe'
\$s.Arguments = '--profile NexusOS -- bash -c \"cd ~/nexus-core && ./launch_nexus.sh ; exec bash\"'
\$s.IconLocation = 'wt.exe,0'
\$s.Save()
" 2>/dev/null && ok "Desktop shortcut created" || warn "Could not create desktop shortcut"
}

step "Windows integration"
if grep -qi microsoft /proc/version 2>/dev/null; then
    setup_windows
else
    ok "Not running in WSL — skipping Windows Terminal setup"
fi

# ── Done ──────────────────────────────────────────────────────────────────────

echo ""
echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
echo "  NexusOS bootstrap complete!"
echo ""
echo "  Launch:   cd ~/nexus-core && ./launch_nexus.sh"
echo "  Frontend: http://localhost:5173"
echo "  Backend:  http://localhost:8000"
echo ""
echo "  Or use the NexusOS shortcut on your Windows desktop."
echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"