#!/usr/bin/env bash
# Генерирует SSH-ключи и ~/.ssh/config для Git-хостов из local/git-ssh-hosts.conf.
set -euo pipefail

CONFIG_DIR="${CONFIG_DIR:-$HOME/CursorRules/local}"
HOSTS_CONFIG="${HOSTS_CONFIG:-$CONFIG_DIR/git-ssh-hosts.conf}"
WHAT_IF="${WHAT_IF:-0}"

log_step() { printf '[*] %s\n' "$1"; }
log_ok() { printf '[+] %s\n' "$1"; }
log_warn() { printf '[!] %s\n' "$1"; }

if [[ ! -f "$HOSTS_CONFIG" ]]; then
  echo "Config not found: $HOSTS_CONFIG" >&2
  exit 1
fi

SSH_DIR="$HOME/.ssh"
SSH_CONFIG="$SSH_DIR/config"
mkdir -p "$SSH_DIR"
chmod 700 "$SSH_DIR"

declare -A PROFILE_KEYNAME PROFILE_COMMENT PROFILE_GITEA
declare -A HOST_HOSTNAME HOST_PORT HOST_USER HOST_PROFILE

current_section=''
current_name=''

while IFS= read -r line || [[ -n "$line" ]]; do
  line="${line%%#*}"
  line="${line%"${line##*[![:space:]]}"}"
  [[ -z "$line" ]] && continue

  if [[ "$line" =~ ^\[profile:(.+)\]$ ]]; then
    current_section='profile'
    current_name="${BASH_REMATCH[1]}"
    continue
  fi
  if [[ "$line" =~ ^\[host:(.+)\]$ ]]; then
    current_section='host'
    current_name="${BASH_REMATCH[1]}"
    HOST_HOSTNAME["$current_name"]=''
    continue
  fi
  if [[ "$line" != *=* ]]; then
    continue
  fi

  key="${line%%=*}"
  value="${line#*=}"
  key="${key%"${key##*[![:space:]]}"}"
  value="${value#"${value%%[![:space:]]*}"}"

  if [[ "$current_section" == 'profile' ]]; then
    case "$key" in
      KeyName) PROFILE_KEYNAME["$current_name"]="$value" ;;
      KeyComment) PROFILE_COMMENT["$current_name"]="$value" ;;
      GiteaConfig) PROFILE_GITEA["$current_name"]="$value" ;;
    esac
  elif [[ "$current_section" == 'host' ]]; then
    case "$key" in
      HostName) HOST_HOSTNAME["$current_name"]="$value" ;;
      Port) HOST_PORT["$current_name"]="$value" ;;
      User) HOST_USER["$current_name"]="$value" ;;
      Profile) HOST_PROFILE["$current_name"]="$value" ;;
    esac
  fi
done < "$HOSTS_CONFIG"

declare -A SEEN_KEYS

for profile in "${!PROFILE_KEYNAME[@]}"; do
  key_name="${PROFILE_KEYNAME[$profile]}"
  [[ -z "$key_name" || -n "${SEEN_KEYS[$key_name]:-}" ]] && continue
  SEEN_KEYS["$key_name"]=1

  key_path="$SSH_DIR/$key_name"
  comment="${PROFILE_COMMENT[$profile]:-$key_name}"

  if [[ ! -f "$key_path" ]]; then
    log_step "Generating $key_name"
    if [[ "$WHAT_IF" == '1' ]]; then
      log_warn "WhatIf: ssh-keygen -t ed25519 -f $key_path"
    else
      ssh-keygen -t ed25519 -f "$key_path" -N '' -C "$comment" -q
      chmod 600 "$key_path"
      log_ok "key $key_name created"
    fi
  else
    log_ok "key $key_name exists"
  fi
done

update_ssh_block() {
  local host_alias="$1"
  local block="$2"
  local begin="# BEGIN Setup-SshAccess:$host_alias"
  local end="# END Setup-SshAccess:$host_alias"
  local tmp
  tmp="$(mktemp)"

  if [[ -f "$SSH_CONFIG" ]]; then
    awk -v begin="$begin" -v end="$end" -v block="$block" '
      $0 == begin { skip=1; next }
      $0 == end { skip=0; next }
      skip { next }
      { print }
      END {
        if (block != "") {
          print block
        }
      }
    ' block="$block" "$SSH_CONFIG" > "$tmp"
  else
    printf '%s\n' "$block" > "$tmp"
  fi

  if [[ "$WHAT_IF" != '1' ]]; then
    mv "$tmp" "$SSH_CONFIG"
    chmod 600 "$SSH_CONFIG"
  else
    rm -f "$tmp"
  fi
}

for host_alias in $(printf '%s\n' "${!HOST_HOSTNAME[@]}" | sort); do
  profile="${HOST_PROFILE[$host_alias]:-}"
  key_name="${PROFILE_KEYNAME[$profile]:-}"
  if [[ -z "$profile" || -z "$key_name" ]]; then
    echo "Host $host_alias: unknown profile" >&2
    exit 1
  fi

  block="# BEGIN Setup-SshAccess:$host_alias
Host $host_alias
    HostName ${HOST_HOSTNAME[$host_alias]}
    User ${HOST_USER[$host_alias]}
    Port ${HOST_PORT[$host_alias]}
    IdentityFile ~/.ssh/$key_name
    IdentitiesOnly yes
    AddKeysToAgent yes
    StrictHostKeyChecking accept-new
# END Setup-SshAccess:$host_alias"

  if [[ "$WHAT_IF" == '1' ]]; then
    log_step "WhatIf: ssh config block for $host_alias"
  else
    update_ssh_block "$host_alias" "$block"
    log_ok "ssh config: $host_alias"
  fi
done

if [[ "$WHAT_IF" != '1' ]]; then
  eval "$(ssh-agent -s)" >/dev/null
  for key_name in "${!SEEN_KEYS[@]}"; do
    [[ -f "$SSH_DIR/$key_name" ]] && ssh-add "$SSH_DIR/$key_name" >/dev/null 2>&1 || true
  done
fi

log_ok 'SSH setup complete'