# Copyright (C) 2016 The Android Open Source Project
#
# 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.

# War packaging.

load("@rules_java//java:defs.bzl", "JavaInfo")

jar_filetype = [".jar"]

# Special prefix added by rules_jvm_external.jvm_import() to stamped jars
# https://github.com/bazel-contrib/rules_jvm_external/blob/6.9/private/rules/jvm_import.bzl#L32
PROCESSED_PREFIX = "processed_"

def war_jar_name(f):
    """Return the jar file name as it will appear inside the WAR."""
    raw = f.basename
    if raw.startswith(PROCESSED_PREFIX):
        raw = raw[len(PROCESSED_PREFIX):]

    sp = f.short_path

    # Rename ONLY caffeine's "guava" artifact (not Google Guava)
    # Matches: .../com/github/ben-manes/caffeine/guava/<ver>/processed_guava-<ver>.jar
    if "/com/github/ben-manes/caffeine/guava/" in sp and raw.startswith("guava-") and raw.endswith(".jar"):
        raw = "caffeine-" + raw  # -> caffeine-guava-<ver>.jar

    # Keep existing Gerrit naming rules
    if sp.startswith("gerrit-"):
        raw = sp.split("/")[0] + "-" + raw
    elif sp.startswith("java/"):
        raw = sp[5:].replace("/", "_")

    return raw

def normalize_jar_id(jar_name):
    """Version-agnostic jar identity used for allowlists/inventories."""
    n = jar_name
    if n.endswith(".jar"):
        n = n[:-4]
    i = n.rfind("-")

    # Strip trailing "-<version-ish>" where the suffix begins with a digit.
    if i > 0 and n[i + 1:i + 2].isdigit():
        n = n[:i]
    return n

def should_skip_packaged_jar(ctx, jar_name):
    """jar_name must be the post-processed name (war_jar_name output)."""
    for pfx in ctx.attr.exclude_jar_prefixes:
        if jar_name.startswith(pfx):
            return True
    return False

def is_third_party_jar_id(ctx, jar_id):
    """Return True if jar_id should be tracked in third-party allowlists."""
    if jar_id in ctx.attr.exclude_third_party_jar:
        return False
    for pfx in ctx.attr.exclude_third_party_jar_prefix:
        if jar_id.startswith(pfx):
            return False
    return True

def _add_context(in_file, output):
    return [
        "unzip -qd %s %s" % (output, in_file.path),
    ]

def _add_jar_file(in_file, output):
    raw = war_jar_name(in_file)
    output_path = output + raw

    return _add_file(in_file.path, output_path)

def _add_web_xml_file(in_file, output):
    return _add_file(in_file.path, output + in_file.basename)

def _add_file(in_file, output):
    return [
        "test -L %s || ln -s $(pwd)/%s %s" % (output, in_file, output),
    ]

def _make_war(input_dir, output):
    return "(%s)" % " && ".join([
        "root=$(pwd)",
        "cd %s" % input_dir,
        "find . -exec touch -t 198001010000 '{}' ';' 2> /dev/null",
        "zip -X -9qr ${root}/%s ." % (output.path),
    ])

def _war_impl(ctx):
    war = ctx.outputs.war
    build_output = war.path + ".build_output"
    inputs = []

    # Metadata we expose for checks/tools.
    jar_entries = []
    jar_ids = []

    # Create war layout
    cmd = [
        "set -e;rm -rf " + build_output,
        "mkdir -p " + build_output,
        "mkdir -p %s/WEB-INF/lib" % build_output,
        "mkdir -p %s/WEB-INF/pgm-lib" % build_output,
    ]

    # Add web.xml files
    if ctx.attr.web_xml:
        for web_xml in ctx.attr.web_xml.files.to_list():
            inputs.append(web_xml)
            cmd = cmd + _add_web_xml_file(web_xml, build_output + "/WEB-INF/")

    # Add runtime libs
    transitive_libs = []
    for l in ctx.attr.libs:
        if JavaInfo in l:
            transitive_libs.append(l[JavaInfo].transitive_runtime_jars)
        elif hasattr(l, "files"):
            transitive_libs.append(l.files)

    for dep in depset(transitive = transitive_libs).to_list():
        packaged = war_jar_name(dep)
        if should_skip_packaged_jar(ctx, packaged):
            continue

        cmd += _add_jar_file(dep, build_output + "/WEB-INF/lib/")
        inputs.append(dep)

        jar_entries.append("WEB-INF/lib/" + packaged)

        jid = normalize_jar_id(packaged)
        if is_third_party_jar_id(ctx,jid):
            jar_ids.append(jid)

    # Add pgm libs
    transitive_pgmlibs = []
    for l in ctx.attr.pgmlibs:
        transitive_pgmlibs.append(l[JavaInfo].transitive_runtime_jars)

    for dep in depset(transitive = transitive_pgmlibs).to_list():
        packaged = war_jar_name(dep)
        if should_skip_packaged_jar(ctx, packaged):
            continue

        if dep not in inputs:
            cmd += _add_jar_file(dep, build_output + "/WEB-INF/pgm-lib/")
            inputs.append(dep)

            jar_entries.append("WEB-INF/pgm-lib/" + packaged)

            jid = normalize_jar_id(packaged)
            if is_third_party_jar_id(ctx, jid):
                jar_ids.append(jid)

    # Add context
    transitive_context_libs = []
    if ctx.attr.context:
        for jar in ctx.attr.context:
            if JavaInfo in jar:
                transitive_context_libs.append(jar[JavaInfo].transitive_runtime_jars)
            elif hasattr(jar, "files"):
                transitive_context_libs.append(jar.files)

    for dep in depset(transitive = transitive_context_libs).to_list():
        cmd += _add_context(dep, build_output)
        inputs.append(dep)

    # Write deterministic manifests for checks.
    #
    # NOTE: The manifests are produced as independent actions.
    # Bazel will only execute the actions needed for the requested output,
    # so building *.war.entries.txt does not materialize the WAR.
    ctx.actions.write(
        output = ctx.outputs.jars,
        content = "\n".join(sorted(depset(jar_ids).to_list())) + "\n",
    )
    ctx.actions.write(
        output = ctx.outputs.entries,
        content = "\n".join(sorted(jar_entries)) + "\n",
    )

    # Add zip war
    cmd.append(_make_war(build_output, war))

    ctx.actions.run_shell(
        inputs = inputs,
        outputs = [war],
        mnemonic = "WAR",
        command = "\n".join(cmd),
        use_default_shell_env = True,
    )

    return [
        DefaultInfo(files = depset([war, ctx.outputs.jars, ctx.outputs.entries])),
    ]

# context: go to the root directory
# libs: go to the WEB-INF/lib directory
# pgmlibs: go to the WEB-INF/pgm-lib directory
# web_xml: go to the WEB-INF directory
_pkg_war = rule(
    attrs = {
        "context": attr.label_list(allow_files = True),
        "libs": attr.label_list(allow_files = jar_filetype),
        "pgmlibs": attr.label_list(allow_files = False),
        "web_xml": attr.label(allow_files = True),
        "exclude_jar_prefixes": attr.string_list(),
        "exclude_third_party_jar": attr.string_list(),
        "exclude_third_party_jar_prefix": attr.string_list(),
    },
    outputs = {
        "war": "%{name}.war",
        "jars": "%{name}.war.jars.txt",
        "entries": "%{name}.war.entries.txt",
    },
    implementation = _war_impl,
)

def pkg_war(name, context = [], **kwargs):
    _pkg_war(
        name = name,
        context = context,
        **kwargs
    )