name: Build & Deploy (Nix)

on:
  push:
    branches:
      - main
  workflow_dispatch:

jobs:
  build-and-deploy:
    runs-on: ubuntu-latest

    steps:
      - name: Check out repository
        run: |
          git clone https://git.imrnes.team/MythEclipse/pr-agent-server.git .
          git checkout ${{ github.sha }}

      - name: Build & Deploy
        env:
          VPS_HOST: ${{ secrets.VPS_HOST }}
          VPS_USER: ${{ secrets.VPS_USER }}
          VPS_SSH_KEY: ${{ secrets.VPS_SSH_KEY }}
        run: |
          set -eu

          # --- Install Nix & Build ---
          curl -fsSL https://install.determinate.systems/nix \
            | sh -s -- install linux --no-confirm --init none 2>&1

          mkdir -p /etc/nix
          echo "experimental-features = nix-command flakes" >> /etc/nix/nix.conf

          . /nix/var/nix/profiles/default/etc/profile.d/nix-daemon.sh

          echo "=== Building: pr-agent-server ==="
          nix build .#default --impure --option sandbox false 2>&1

          STORE_PATH=$(readlink result)
          echo "=== Store path: $STORE_PATH"

          # --- Deploy ---
          NIX_BIN="/nix/var/nix/profiles/default/bin"
          PROFILE="/nix/var/nix/profiles/pr-agent-server"

          key_file=$(mktemp /tmp/deploy-key.XXXXXX)
          # VPS_SSH_KEY may be stored base64-encoded (multiline corruption workaround)
          if printf '%s' "$VPS_SSH_KEY" | base64 -d 2>/dev/null | head -c 6 | grep -q "BEGIN"; then
            printf '%s' "$VPS_SSH_KEY" | base64 -d > "$key_file"
          else
            printf '%s\n' "$VPS_SSH_KEY" > "$key_file"
          fi
          chmod 600 "$key_file"
          sed -i 's/\r$//' "$key_file"          # strip DOS line endings if any
          ssh-keygen -y -f "$key_file" >/dev/null 2>&1 || { echo "SSH key invalid"; exit 1; }

          export NIX_SSHOPTS="-i $key_file -o StrictHostKeyChecking=no"
          nix copy --to "ssh://${VPS_USER}@${VPS_HOST}" "$STORE_PATH" 2>&1

          ssh -i "$key_file" -o StrictHostKeyChecking=no \
            "${VPS_USER}@${VPS_HOST}" "
            export PATH=\$PATH:$NIX_BIN
            if [ -d $PROFILE ] && [ ! -L $PROFILE ]; then
              rm -rf $PROFILE
            fi
            nix-env --profile $PROFILE --set $STORE_PATH
            systemctl daemon-reload
            systemctl restart pr-agent-server
            sleep 3
            systemctl status pr-agent-server --no-pager 2>&1 | head -12
          " 2>&1