#include <catch2/catch_test_macros.hpp>

import cargoxx.cli;
import cargoxx.linkdb;
import cargoxx.manifest;
import cargoxx.lockfile;
import cargoxx.util;
import std;

using cargoxx::cli::cmd_build;
using cargoxx::cli::cmd_new;
using cargoxx::linkdb::Database;
using cargoxx::linkdb::Recipe;
using cargoxx::util::ErrorCode;
namespace manifest = cargoxx::manifest;
namespace lockfile = cargoxx::lockfile;

namespace {

auto fresh_dir() -> std::filesystem::path {
    auto d = std::filesystem::temp_directory_path() /
             std::format("cargoxx-build-test-{}", std::random_device{}());
    std::filesystem::create_directories(d);
    return d;
}

auto overlay_path(const std::filesystem::path& dir) -> std::filesystem::path {
    return dir / "overlay.sqlite";
}

auto read_file(const std::filesystem::path& p) -> std::string {
    std::ifstream in{p};
    return std::string{std::istreambuf_iterator<char>(in), {}};
}

auto add_dep(const std::filesystem::path& root, const std::string& name,
             const std::string& version_spec, std::vector<std::string> components = {}) {
    auto path = root / "Cargoxx.toml";
    auto m = manifest::parse(path);
    REQUIRE(m.has_value());
    m->dependencies.push_back(manifest::Dependency{
        .name = name,
        .version_spec = version_spec,
        .components = std::move(components),
    });
    REQUIRE(manifest::write(*m, path).has_value());
}

auto seed_recipe(const std::filesystem::path& overlay, const std::string& package,
                 const std::string& version_range, const Recipe& r) {
    auto db = Database::open(overlay);
    REQUIRE(db.has_value());
    REQUIRE(db->add_manual(package, version_range, r).has_value());
}

} // namespace

TEST_CASE("cmd_build generates files for a no-deps binary project",
          "[cli][build]") {
    auto parent = fresh_dir();
    REQUIRE(cmd_new("hello", false, parent).has_value());
    auto root = parent / "hello";

    auto r = cmd_build(root, true, false, std::nullopt, overlay_path(parent));
    REQUIRE(r.has_value());

    REQUIRE(std::filesystem::exists(root / "build" / "flake.nix"));
    REQUIRE(std::filesystem::exists(root / "build" / "CMakeLists.txt"));
    REQUIRE(std::filesystem::exists(root / "Cargoxx.lock"));

    auto cmake_text = read_file(root / "build" / "CMakeLists.txt");
    REQUIRE(cmake_text.find("project(hello VERSION 0.1.0 LANGUAGES CXX)") != std::string::npos);
    REQUIRE(cmake_text.find("add_executable(hello_bin ../src/main.cpp)") !=
            std::string::npos);

    auto flake_text = read_file(root / "build" / "flake.nix");
    REQUIRE(flake_text.find("description = \"hello\";") != std::string::npos);
    REQUIRE(flake_text.find("github:NixOS/nixpkgs/") != std::string::npos);
}

TEST_CASE("cmd_build generates files for a library project", "[cli][build]") {
    auto parent = fresh_dir();
    REQUIRE(cmd_new("widget", true, parent).has_value());
    auto root = parent / "widget";

    auto r = cmd_build(root, true, false, std::nullopt, overlay_path(parent));
    REQUIRE(r.has_value());

    auto cmake_text = read_file(root / "build" / "CMakeLists.txt");
    REQUIRE(cmake_text.find("add_library(widget STATIC)") != std::string::npos);
    REQUIRE(cmake_text.find("../src/lib.cppm") != std::string::npos);
    REQUIRE(cmake_text.find("add_executable") == std::string::npos);
}

TEST_CASE("cmd_build resolves a manually-seeded dep into find_package + targets",
          "[cli][build]") {
    auto parent = fresh_dir();
    REQUIRE(cmd_new("app", false, parent).has_value());
    auto root = parent / "app";
    add_dep(root, "fmt", "10.2.0");
    seed_recipe(overlay_path(parent), "fmt", ">=10.0.0",
                Recipe{
                    .nixpkgs_attr = "fmt_10",
                    .find_package = "fmt CONFIG REQUIRED",
                    .targets = {"fmt::fmt"},
                    .source = "manual",
                });

    auto r = cmd_build(root, true, false, std::nullopt, overlay_path(parent));
    REQUIRE(r.has_value());

    auto cmake_text = read_file(root / "build" / "CMakeLists.txt");
    REQUIRE(cmake_text.find("find_package(fmt CONFIG REQUIRED)") != std::string::npos);
    REQUIRE(cmake_text.find("fmt::fmt") != std::string::npos);

    auto flake_text = read_file(root / "build" / "flake.nix");
    REQUIRE(flake_text.find("pkgs.fmt_10") != std::string::npos);
}

TEST_CASE("cmd_build synthesizes a lockfile entry per dep", "[cli][build]") {
    auto parent = fresh_dir();
    REQUIRE(cmd_new("app", false, parent).has_value());
    auto root = parent / "app";
    add_dep(root, "fmt", "10.2.0");
    add_dep(root, "spdlog", "1.13.0");
    seed_recipe(overlay_path(parent), "fmt", ">=10.0.0",
                Recipe{
                    .nixpkgs_attr = "fmt_10",
                    .find_package = "fmt CONFIG REQUIRED",
                    .targets = {"fmt::fmt"},
                    .source = "manual",
                });
    seed_recipe(overlay_path(parent), "spdlog", "*",
                Recipe{
                    .nixpkgs_attr = "spdlog",
                    .find_package = "spdlog CONFIG REQUIRED",
                    .targets = {"spdlog::spdlog"},
                    .source = "manual",
                });

    auto r = cmd_build(root, true, false, std::nullopt, overlay_path(parent));
    REQUIRE(r.has_value());

    auto lock = lockfile::parse(root / "Cargoxx.lock");
    REQUIRE(lock.has_value());
    REQUIRE(lock->packages.size() == 3);
    REQUIRE(lock->packages[0].name == "app");
    REQUIRE(lock->packages[0].dependencies.size() == 2);
}

TEST_CASE("cmd_build fails for an unknown dep", "[cli][build]") {
    auto parent = fresh_dir();
    REQUIRE(cmd_new("app", false, parent).has_value());
    auto root = parent / "app";
    add_dep(root, "obscurelib", "0.0.1");

    auto r = cmd_build(root, true, false, std::nullopt, overlay_path(parent));
    REQUIRE_FALSE(r.has_value());
    REQUIRE(r.error().code == ErrorCode::ResolutionUnknownPackage);
}

TEST_CASE("cmd_build --release writes a release-typed build/CMakeLists",
          "[cli][build]") {
    // The CMAKE_BUILD_TYPE flag itself is set on the cmake command line, not in
    // the generated CMakeLists.txt — but the same generation runs for both
    // profiles, so just verify the --release path with --no-build doesn't error.
    auto parent = fresh_dir();
    REQUIRE(cmd_new("app", false, parent).has_value());
    auto root = parent / "app";
    auto r = cmd_build(root, true, true, std::nullopt, overlay_path(parent));
    REQUIRE(r.has_value());
}

TEST_CASE("cmd_build accepts a --target argument under --no-build",
          "[cli][build]") {
    auto parent = fresh_dir();
    REQUIRE(cmd_new("app", false, parent).has_value());
    auto root = parent / "app";
    auto r = cmd_build(root, true, false, std::string{"app_bin"},
                       overlay_path(parent));
    REQUIRE(r.has_value());
}

TEST_CASE("cmd_build is idempotent — second run produces identical files",
          "[cli][build]") {
    auto parent = fresh_dir();
    REQUIRE(cmd_new("app", false, parent).has_value());
    auto root = parent / "app";
    add_dep(root, "fmt", "10.2.0");
    seed_recipe(overlay_path(parent), "fmt", ">=10.0.0",
                Recipe{
                    .nixpkgs_attr = "fmt_10",
                    .find_package = "fmt CONFIG REQUIRED",
                    .targets = {"fmt::fmt"},
                    .source = "manual",
                });

    REQUIRE(cmd_build(root, true, false, std::nullopt, overlay_path(parent)).has_value());
    auto first_cmake = read_file(root / "build" / "CMakeLists.txt");
    auto first_flake = read_file(root / "build" / "flake.nix");
    auto first_lock = read_file(root / "Cargoxx.lock");

    REQUIRE(cmd_build(root, true, false, std::nullopt, overlay_path(parent)).has_value());
    REQUIRE(read_file(root / "build" / "CMakeLists.txt") == first_cmake);
    REQUIRE(read_file(root / "build" / "flake.nix") == first_flake);
    REQUIRE(read_file(root / "Cargoxx.lock") == first_lock);
}