#!/usr/bin/env bash
# Deployment script for both NixOS configs and individual services.
#
# Usage:
#   push.sh Biz.nix              # NixOS deploy (existing behavior)
#   push.sh Biz/PodcastItLater/Web.py  # Service deploy (new behavior)
#
# For service deploys:
#   1. Builds the target with bild (caches to S3 by default)
#   2. Updates the manifest.json in S3 with new store path
#   3. Deployer on target picks up change within 5 minutes
#
# Environment:
#   CODEROOT - Root of the codebase (required)
#   NIX_CACHE_KEY - Path to signing key (required for service deploys)

set -euo pipefail

# Colors
GRN='\033[0;32m'
YLW='\033[0;33m'
RED='\033[0;31m'
NC='\033[0m' # No Color

# Derive service name from target path
# Biz/PodcastItLater/Web.py -> podcastitlater-web
# Biz/Storybook.py -> storybook
derive_service_name() {
    local target="$1"
    # Remove extension
    local base="${target%.*}"
    # Remove Biz/ prefix if present
    base="${base#Biz/}"
    # Convert slashes to hyphens and lowercase
    echo "$base" | tr '/' '-' | tr '[:upper:]' '[:lower:]'
}

# NixOS deploy (existing behavior)
nixos_deploy() {
    local target="$1"
    prefix=${PWD/$CODEROOT}
    if [[ "$prefix" == "" ]]; then
        target="$1"
    else
        target="$prefix.$1"
    fi
    what=$(realpath "${CODEROOT:?}/_/nix/$target")
    # hack: get the domain from the systemd service
    where=$(rg --only-matching --replace '$2' --regexp '(domainname ")(.*)(")' \
        "$what/etc/systemd/system/domainname.service")
    nix copy --to ssh://"$USER"@"$where" "$what"
    ssh "$USER"@"$where" sudo nix-env --profile /nix/var/nix/profiles/system --set "$what"
    switch_cmd=(
        systemd-run
        -E LOCALE_ARCHIVE
        --setenv=XDG_RUNTIME_DIR=""
        --collect
        --no-ask-password
        --pipe
        --quiet
        --service-type=exec
        --unit=push-switch-to-configuration
        --wait
        "$what/bin/switch-to-configuration"
        "switch"
    )
    # shellcheck disable=SC2029
    ssh "$USER"@"$where" sudo "${switch_cmd[@]}"
    echo -e "${GRN}good:  push:  $target${NC}"
}

# Service deploy (new behavior)
service_deploy() {
    local target="$1"
    local service_name
    service_name=$(derive_service_name "$target")

    echo -e "${YLW}info:  push:  deploying service $service_name${NC}"

    # 1. Build and cache
    echo -e "${YLW}info:  push:  building $target${NC}"
    if ! bild "$target"; then
        echo -e "${RED}fail:  push:  bild failed${NC}"
        exit 1
    fi

    # Get store path from symlink in _/nix/
    local symlink_path="${CODEROOT}/_/nix/${service_name}"
    if [[ ! -L "$symlink_path" ]]; then
        echo -e "${RED}fail:  push:  symlink not found: $symlink_path${NC}"
        exit 1
    fi

    local store_path
    store_path=$(readlink "$symlink_path")

    if [[ -z "$store_path" ]]; then
        echo -e "${RED}fail:  push:  could not read store path from symlink${NC}"
        exit 1
    fi

    echo -e "${YLW}info:  push:  cached $store_path${NC}"

    # 2. Get git revision
    local revision
    revision=$(git rev-parse --short HEAD 2>/dev/null || echo "unknown")

    # 3. Update manifest in S3
    echo -e "${YLW}info:  push:  updating manifest${NC}"
    "${CODEROOT}/_/nix/deploy-manifest/bin/deploy-manifest" update "$service_name" "$store_path" "$revision" || {
        echo -e "${RED}fail:  push:  manifest update failed${NC}"
        exit 1
    }

    echo -e "${GRN}good:  push:  $service_name deployed (deployer will pick up in <5 min)${NC}"
}

# Main
main() {
    if [[ $# -lt 1 ]]; then
        echo "Usage: push.sh <target>"
        echo "  target.nix       -> NixOS deploy"
        echo "  target.py/.hs/.. -> Service deploy"
        exit 1
    fi

    local target="$1"

    if [[ "$target" == *.nix ]]; then
        nixos_deploy "$target"
    else
        service_deploy "$target"
    fi
}

main "$@"