#!/bin/bash
# Copyright 2020 The Fuchsia Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

#### CATEGORY=Source tree
### regenerates golden files in the source tree

## Usage: fx regen-goldens PATTERN ... [--list] [--reset] [FX_TEST_FLAGS]
##
## Regenerates golden files for tools that match the given substring patterns.
## If no patterns are provided, regenerates for all tools.
##
##   --list   List matching tools and their golden directories, and exit.
##   --reset  Delete existing goldens first. (See "Troubleshooting" below.)
## 
##   All other flags are forwarded to fx test. A useful one is -o/--output to
##   show test output, which prints the filenames being regenerated.
##
## Examples:
##
##   fx regen-goldens           # regen all goldens
##   fx regen-goldens fidlgen_  # regen fidlgen_* goldens
##   fx regen-goldens fidlc -o  # regen fidlc goldens, with verbose output
##
## Troubleshooting:
##
##   Try passing the --reset flag if you encounter one of these situations:
##
##   GN error, when goldens.txt is missing:
##     ERROR at //build/testing/golden_test.gni:86:28: Could not read file.
##       goldens_list = read_file("${invoker.goldens_dir}/goldens.txt", ...)
##
##   Ninja error, when goldens.txt contains nonexistent files:
##     ninja: error: '.../foo.golden', needed by 'host_x64/gen/.../foo.golden',
##     missing and no known rule to make it
##
##   Formatting error, when goldens have invalid syntax (e.g. from a merge conflict):
##     ACTION //..._reformat_goldens(//build/toolchain:host_x64)
##     /usr/bin/env /bin/sh -c \'.../rustfmt\'\ ...
##     error: expected identifier, found `<<`

set -eo pipefail

source "$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)"/../lib/vars.sh || exit $?
fx-config-read

# Each tool $t has a NAME=${t%% *} and DIR=${t##* }, for which there must exist
# $(dirname $DIR)/BUILD.gn containing golden_test("${NAME}_golden_tests") with
# goldens_dir="$(basename $DIR)", and also group("tests") containing
# ":${NAME}_golden_tests($host_toolchain)". See //build/testing/golden_test.gni
# for more information about golden tests.
#
# Please keep this list sorted alphabetically.
readonly all_tools=(
    "fidlc tools/fidl/fidlc/goldens"
    "fidldoc tools/fidl/fidldoc/goldens"
    "fidlgen_dart tools/fidl/fidlgen_dart/goldens"
    "fidlgen_go tools/fidl/fidlgen_go/goldens"
    "fidlgen_hlcpp tools/fidl/fidlgen_hlcpp/goldens"
    "fidlgen_libfuzzer tools/fidl/fidlgen_libfuzzer/goldens"
    "fidlgen_llcpp tools/fidl/fidlgen_llcpp/goldens"
    "fidlgen_rust tools/fidl/fidlgen_rust/goldens"
    "fidlgen_syzkaller tools/fidl/fidlgen_syzkaller/goldens"
    "gidl tools/fidl/gidl/goldens"
)

# This environment variable is only set during tests.
# See //tools/devshell/tests/subcommands/fx_regen_goldens_test.
if [[ -z ${REGEN_GOLDENS_SKIP_CHECK+x} ]]; then
    for t in "${all_tools[@]}"; do
        dir=${t##* }
        if ! [[ -d "$FUCHSIA_DIR/$dir" ]]; then
            echo "WARNING: regen-goldens has invalid goldens dir '$dir'" >&2
        fi
    done
fi

tools=()
flags=()
list=false
reset=false

for arg in "$@"; do
    case $arg in
        -h|--help) fx-command-help; exit ;;
        --list) list=true ;;
        --reset) reset=true ;;
        -*) flags+=("$arg") ;;
        *)
            found=false
            for t in "${all_tools[@]}"; do
                if [[ "${t%% *}" == *"$arg"* ]]; then
                    tools+=("$t")
                    found=true
                fi
            done
            if [[ "$found" == false ]]; then
                echo "No tools match the pattern '$arg'." >&2
                echo "Run \`fx regen-goldens --list\` to see supported tools." >&2
                exit 1
            fi
            ;;
    esac
done

if [[ "${#tools[@]}" -eq 0 ]]; then
    tools=("${all_tools[@]}")
fi

if [[ $list == true ]]; then
    { IFS=$'\n'; lines=${tools[*]}; }
    column -t <<< "$lines"
    exit
fi

if [[ $reset == true ]]; then
    for t in "${tools[@]}"; do
        echo "Deleting goldens for: ${t%% *}"
        dir="$FUCHSIA_DIR/${t##* }"
        if ! [[ -d "$dir" ]]; then
            echo "ERROR: directory not found: $dir" >&2
            exit 1
        fi
        find "$dir" -maxdepth 1 -type f -name "*.golden" -delete
        echo -n > "$dir/goldens.txt"
    done
fi

tests=()
for t in "${tools[@]}"; do
    tests+=("${t%% *}_golden_tests")
done

echo "Regenerating goldens for: ${tools[*]%% *}"
exit_code=0
"$(find_executable test)" "${tests[@]}" "${flags[@]}" -- --regen || exit_code=$?

# The fx test exit codes are defined in scripts/fxtest/lib/constants.dart.
case $exit_code in
    2) # fatal error (all "Troubleshooting" examples exit with code 2)
        if [[ $reset == false ]]; then
            echo
            echo "Hint: Try again with --reset: \`fx regen-goldens $* --reset\`"
        fi
        ;;
    3) # test not found
        echo "Error: Could not find test targets needed to regenerate goldens"
        with=()
        for t in "${tools[@]}"; do
            parent=$(dirname "${t##* }")
            target="//$parent:${t%% *}_golden_tests"
            if ! fx-command-run jq -e \
                    "any(.test.label | startswith(\"$target\"))" \
                    "$FUCHSIA_BUILD_DIR/tests.json" > /dev/null; then
                with+=("--with" "//$parent:tests")
            fi
        done
        if [[ ${#with[@]} -gt 0 ]]; then
            echo "Hint: Try again after \`fx set ... ${with[*]}\`"
        fi
        ;;
esac
exit $exit_code