// Copyright (C) 2026 Viorel Munteanu
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

// [unit] tests for resolve_env_specs() (env_spec.h). The --env-file case
// needs a real file on disk -- a tiny local RAII helper below writes one
// to a unique path under /tmp and removes it in its destructor, so a
// REQUIRE-triggered early return from within a TEST_CASE still cleans up
// (unlike the real host-state tests under tests/integration/, a stray
// leftover file here is harmless but there's no reason to leave one).

#include <unistd.h>

#include <cstdio>
#include <fstream>
#include <string>

#include <catch2/catch_test_macros.hpp>
#include <fmt/core.h>

#include "env_spec.h"

namespace {

class ScratchFile {
public:
    explicit ScratchFile(const std::string& content) : path_(fmt::format("/tmp/slocker-lite-test-env-{}", getpid())) {
        std::ofstream out(path_);
        out << content;
    }
    ~ScratchFile() { std::remove(path_.c_str()); }
    ScratchFile(const ScratchFile&) = delete;
    ScratchFile& operator=(const ScratchFile&) = delete;

    const std::string& path() const { return path_; }

private:
    std::string path_;
};

}  // namespace

TEST_CASE("resolve_env_specs: a single literal --env", "[unit]") {
    auto resolved = resolve_env_specs({{false, "FOO=bar"}});
    REQUIRE(resolved.has_value());
    REQUIRE(resolved->size() == 1);
    CHECK((*resolved)[0].first == "FOO");
    CHECK((*resolved)[0].second == "bar");
}

TEST_CASE("resolve_env_specs: splits at the first '=' only, value may contain '='", "[unit]") {
    auto resolved = resolve_env_specs({{false, "FOO=bar=baz"}});
    REQUIRE(resolved.has_value());
    REQUIRE(resolved->size() == 1);
    CHECK((*resolved)[0].first == "FOO");
    CHECK((*resolved)[0].second == "bar=baz");
}

TEST_CASE("resolve_env_specs: later --env for the same key is kept (append-order, last wins by convention)",
          "[unit]") {
    auto resolved = resolve_env_specs({{false, "FOO=first"}, {false, "FOO=second"}});
    REQUIRE(resolved.has_value());
    REQUIRE(resolved->size() == 2);
    CHECK((*resolved)[0].second == "first");
    CHECK((*resolved)[1].second == "second");
}

TEST_CASE("resolve_env_specs: rejects a literal with no '='", "[unit]") {
    CHECK_FALSE(resolve_env_specs({{false, "NOEQUALS"}}).has_value());
}

TEST_CASE("resolve_env_specs: rejects an empty key", "[unit]") {
    CHECK_FALSE(resolve_env_specs({{false, "=value"}}).has_value());
}

TEST_CASE("resolve_env_specs: rejects a missing --env-file", "[unit]") {
    CHECK_FALSE(resolve_env_specs({{true, "/nonexistent/path/slocker-lite-test-env-file"}}).has_value());
}

TEST_CASE("resolve_env_specs: --env-file skips blank lines and #-comments", "[unit]") {
    ScratchFile file(
        "# a comment\n"
        "\n"
        "   \n"
        "FOO=bar\n"
        "  # indented comment\n"
        "BAZ=qux\n");
    auto resolved = resolve_env_specs({{true, file.path()}});
    REQUIRE(resolved.has_value());
    REQUIRE(resolved->size() == 2);
    CHECK((*resolved)[0].first == "FOO");
    CHECK((*resolved)[0].second == "bar");
    CHECK((*resolved)[1].first == "BAZ");
    CHECK((*resolved)[1].second == "qux");
}

TEST_CASE("resolve_env_specs: --env-file strips a trailing '\\r' (CRLF files)", "[unit]") {
    ScratchFile file("FOO=bar\r\n");
    auto resolved = resolve_env_specs({{true, file.path()}});
    REQUIRE(resolved.has_value());
    REQUIRE(resolved->size() == 1);
    CHECK((*resolved)[0].second == "bar");
}

TEST_CASE("resolve_env_specs: --env-file with a malformed line fails the whole file, not skip-and-warn", "[unit]") {
    ScratchFile file(
        "GOOD=1\n"
        "NOEQUALS\n");
    CHECK_FALSE(resolve_env_specs({{true, file.path()}}).has_value());
}

TEST_CASE("resolve_env_specs: --env and --env-file interleave in exact command-line order", "[unit]") {
    ScratchFile file("FOO=from-file\n");
    auto resolved = resolve_env_specs({{false, "FOO=from-cli-1"}, {true, file.path()}, {false, "FOO=from-cli-2"}});
    REQUIRE(resolved.has_value());
    REQUIRE(resolved->size() == 3);
    CHECK((*resolved)[0].second == "from-cli-1");
    CHECK((*resolved)[1].second == "from-file");
    CHECK((*resolved)[2].second == "from-cli-2");
}

TEST_CASE("resolve_env_specs: empty spec list resolves to an empty list", "[unit]") {
    auto resolved = resolve_env_specs({});
    REQUIRE(resolved.has_value());
    CHECK(resolved->empty());
}