#!/bin/bash

# Copyright 2014 The Kubernetes Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# Controls verbosity of the script output and logging.
setglobal KUBE_VERBOSE = $(KUBE_VERBOSE:-5)

# Handler for when we exit automatically on an error.
# Borrowed from https://gist.github.com/ahendrix/7030300
proc kube::log::errexit {
  local err="$(PIPESTATUS[@])"

  # If the shell we are in doesn't have errexit set (common in subshells) then
  # don't dump stacks.
  set +o | grep -qe "-o errexit" || return

  set +o xtrace
  local code="$(1:-1)"
  # Print out the stack trace described by $function_stack  
  if test $(#FUNCNAME[@]) -gt 2
  {
    kube::log::error "Call tree:"
    for ((i=1;i<${#FUNCNAME[@]}-1;i++))
    do
      kube::log::error " $i: ${BASH_SOURCE[$i+1]}:${BASH_LINENO[$i]} ${FUNCNAME[$i]}(...)"
    done
  }  
  kube::log::error_exit "Error in $(BASH_SOURCE[1]):$(BASH_LINENO[0]). '$(BASH_COMMAND)' exited with status $err" $(1:-1) 1
}

proc kube::log::install_errexit {
  # trap ERR to provide an error handler whenever a command exits nonzero  this
  # is a more verbose version of set -o errexit
  trap 'kube::log::errexit' ERR

  # setting errtrace allows our ERR trap handler to be propagated to functions,
  # expansions and subshells
  set -o errtrace
}

# Print out the stack trace
#
# Args:
#   $1 The number of stack frames to skip when printing.
proc kube::log::stack {
  local stack_skip=$(1:-0)
  setglobal stack_skip = $shExpr('stack_skip + 1')
  if [[ ${#FUNCNAME[@]} -gt $stack_skip ]] {
    echo "Call stack:" > !2
    local i
    for ((i=1 ; i <= ${#FUNCNAME[@]} - $stack_skip ; i++))
    do
      local frame_no=$((i - 1 + stack_skip))
      local source_file=${BASH_SOURCE[$frame_no]}
      local source_lineno=${BASH_LINENO[$((frame_no - 1))]}
      local funcname=${FUNCNAME[$frame_no]}
      echo "  $i: ${source_file}:${source_lineno} ${funcname}(...)" >&2
    done
  }
}

# Log an error and exit.
# Args:
#   $1 Message to log with the error
#   $2 The error code to return
#   $3 The number of stack frames to skip when printing.
proc kube::log::error_exit {
  local message="$(1:-)"
  local code="$(2:-1)"
  local stack_skip="$(3:-0)"
  setglobal stack_skip = $shExpr('stack_skip + 1')

  if [[ ${KUBE_VERBOSE} -ge 4 ]] {
    local source_file=$(BASH_SOURCE[$stack_skip])
    local source_line=$(BASH_LINENO[$((stack_skip - 1))])
    echo "!!! Error in $(source_file):$(source_line)" > !2
    [[ -z ${1-} ]] || do {
      echo "  $(1)" > !2
    }

    kube::log::stack $stack_skip

    echo "Exiting with status $(code)" > !2
  }

  exit "${code}"
}

# Log an error but keep going.  Don't dump the stack or exit.
proc kube::log::error {
  setglobal timestamp = $[date +"[%m%d %H:%M:%S]]
  echo "!!! $timestamp $(1-)" > !2
  shiftfor message in @Argv {
    echo "    $message" > !2
  }
}

# Print an usage message to stderr.  The arguments are printed directly.
proc kube::log::usage {
  echo > !2
  local messagefor message in @Argv {
    echo $message > !2
  }
  echo > !2
}

proc kube::log::usage_from_stdin {
  local messages=()
  while read -r line {
    setglobal messages = ''("$line")
  }

  kube::log::usage $(messages[@])
}

# Print out some info that isn't a top level status line
proc kube::log::info {
  local V="$(V:-0)"
  if [[ $KUBE_VERBOSE < $V ]] {
    return
  }for message in @Argv {
    echo $message
  }
}

# Just like kube::log::info, but no \n, so you can make a progress bar
proc kube::log::progressfor message in @Argv {
    echo -e -n $message
  }
}

proc kube::log::info_from_stdin {
  local messages=()
  while read -r line {
    setglobal messages = ''("$line")
  }

  kube::log::info $(messages[@])
}

# Print a status line.  Formatted to show up in a stream of output.
proc kube::log::status {
  local V="$(V:-0)"
  if [[ $KUBE_VERBOSE < $V ]] {
    return
  }

  setglobal timestamp = $[date +"[%m%d %H:%M:%S]]
  echo "+++ $timestamp $1"
  shiftfor message in @Argv {
    echo "    $message"
  }
}