#!/bin/bash
# Copyright 2016 The Bazel Authors. All rights reserved.
#
# 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.

set -eu

const OUTPUT = "$(PWD)/$1"
shift
const JEKYLL_BASE = "$(PWD)/$1"
shift
const SKYLARK_RULE_DOCS = "$(PWD)/$1"
shift
const BE_ZIP = "$(PWD)/$1"
shift
const SL_ZIP = "$(PWD)/$1"
shift
const CLR_HTML = "$(PWD)/$1"

# Create temporary directory that is removed when this script exits.
const TMP = $[mktemp -d "$(TMPDIR:-/tmp)/tmp.XXXXXXXX]
const OUT_DIR = ""$TMP/out""
trap "rm -rf $(TMP)" EXIT

proc setup {
  mkdir -p $OUT_DIR
  cd $OUT_DIR
  tar -xf $(JEKYLL_BASE)
}

# Unpack the Build Encyclopedia into docs/be
proc unpack_build_encyclopedia {
  var be_dir = ""$OUT_DIR/versions/master/docs/be""
  mkdir -p $be_dir
  unzip -qq $BE_ZIP -d $be_dir
  mv "$be_dir/be-nav.html" "$OUT_DIR/_includes"

  # Create redirects to each page in the Build Encyclopedia.
  mkdir -p "$OUT_DIR/docs/be"
  for f in [$[find "$OUT_DIR/versions/master/docs/be" -name "*.html]] {
    var filename = $[basename $f]
    cat > "$OUT_DIR/docs/be/$(filename)" << """
---
layout: redirect
redirect: docs/be/$(filename)
---
"""
  }
}

# Unpack the Skylark Library into docs/skylark/lib
proc unpack_skylark_library {
  var sl_dir = ""$OUT_DIR/versions/master/docs/skylark/lib""
  mkdir -p $sl_dir
  unzip -qq $SL_ZIP -d $sl_dir
  mv "$sl_dir/skylark-nav.html" "$OUT_DIR/_includes"

  # Create redirects to each page in the Skylark Library
  mkdir -p "$OUT_DIR/docs/skylark/lib"
  for f in [$[find "$OUT_DIR/versions/master/docs/skylark/lib" -name "*.html]] {
    var filename = $[basename $f]
    cat > "$OUT_DIR/docs/skylark/lib/$(filename)" << """
---
layout: redirect
redirect: docs/skylark/lib/$(filename)
---
"""
  }
}

proc copy_skylark_rule_doc {
  var rule_family = $1
  var rule_family_name = $2
  var be_dir = ""$OUT_DIR/versions/master/docs/be""

  shell { cat << """
---
layout: documentation
title: $(rule_family_name) Rules
---
"""
    cat "$TMP/skylark/$rule_family/README.md"; } > "$be_dir/${rule_family}.md"
}

proc unpack_skylark_rule_docs {
  var tmp_dir = "$TMP/skylark"
  mkdir -p $tmp_dir
  cd $tmp_dir
  tar -xf $(SKYLARK_RULE_DOCS)
  copy_skylark_rule_doc docker "Docker"
  copy_skylark_rule_doc pkg "Packaging"
}

proc process_doc {
  var f = $1
  var tempf = $[mktemp -t bazel-doc-XXXXXX]

  chmod +w $f
  cat $f | sed 's,\.md,.html,g;s,Blaze,Bazel,g;s,blaze,bazel,g' > $tempf
  cat $tempf > $f
}

proc process_docs {
  for f in [$[find "$OUT_DIR/versions/master/docs" -name "*.html]] {
    process_doc $f
  }
  for f in [$[find "$OUT_DIR/versions/master/docs" -name "*.md]] {
    process_doc $f
  }
  for f in [$[find "$OUT_DIR/designs" -name "*.md]] {
    process_doc $f
  }
}

proc package_output {
  cd $OUT_DIR
  tar -hcf $OUTPUT $[find . -type f | sort]
}

proc main {
  setup
  unpack_build_encyclopedia
  unpack_skylark_library
  unpack_skylark_rule_docs
  cp $(CLR_HTML) $(OUT_DIR)/versions/master/docs
  process_docs
  package_output
}
main