#include "access.hpp"

#include "common/time_utils.hpp"
#include "common/uuid.hpp"
#include "logging/logger.hpp"

namespace smartbotic::webserver::auth {

using namespace common;

namespace {
constexpr const char* PROJECTS = "projects";
}

InstanceRole instanceRoleFromString(const std::string& role) {
    if (role == "owner") return InstanceRole::Owner;
    if (role == "admin") return InstanceRole::Admin;
    // "user" is what the role was called before there were three of them, and
    // stored accounts still say it.
    return InstanceRole::Member;
}

std::string instanceRoleToString(InstanceRole role) {
    switch (role) {
        case InstanceRole::Owner: return "owner";
        case InstanceRole::Admin: return "admin";
        case InstanceRole::Member: return "member";
    }
    return "member";
}

ProjectRole projectRoleFromString(const std::string& role) {
    if (role == "admin") return ProjectRole::Admin;
    if (role == "editor") return ProjectRole::Editor;
    if (role == "viewer") return ProjectRole::Viewer;
    return ProjectRole::None;
}

std::string projectRoleToString(ProjectRole role) {
    switch (role) {
        case ProjectRole::Admin: return "admin";
        case ProjectRole::Editor: return "editor";
        case ProjectRole::Viewer: return "viewer";
        case ProjectRole::None: return "none";
    }
    return "none";
}

AccessControl::AccessControl(storage::StorageClient& storage) : storage_(storage) {}

std::string AccessControl::projectOf(const nlohmann::json& record) {
    return record.value("projectId", std::string());
}

std::unordered_set<std::string> AccessControl::projectsFor(const AuthContext& ctx) {
    std::unordered_set<std::string> out;

    storage::QueryOptions options;
    options.page_size = 1000;
    auto result = storage_.query(PROJECTS, options);
    if (result.failed()) {
        LOG_WARN("Could not read projects for access check: {}", result.error().message());
        return out;
    }

    const bool sees_everything = instanceRoleFromString(ctx.role) != InstanceRole::Member;

    for (const auto& project : result.value().documents) {
        const std::string id = project.value("_id", "");
        if (id.empty()) continue;

        if (sees_everything) {
            out.insert(id);
            continue;
        }
        if (project.value("ownerId", "") == ctx.user_id) {
            out.insert(id);
            continue;
        }
        for (const auto& member : project.value("members", nlohmann::json::array())) {
            if (member.value("userId", "") == ctx.user_id) {
                out.insert(id);
                break;
            }
        }
    }
    return out;
}

ProjectRole AccessControl::roleIn(const AuthContext& ctx, const std::string& project_id) {
    if (instanceRoleFromString(ctx.role) != InstanceRole::Member) {
        return ProjectRole::Admin;
    }
    if (project_id.empty()) return ProjectRole::None;

    auto project = storage_.get(PROJECTS, project_id);
    if (project.failed()) return ProjectRole::None;

    // A personal project belongs entirely to its owner - there is no
    // membership row to look up and none can be added.
    if (project.value().value("ownerId", "") == ctx.user_id) return ProjectRole::Admin;

    for (const auto& member : project.value().value("members", nlohmann::json::array())) {
        if (member.value("userId", "") == ctx.user_id) {
            return projectRoleFromString(member.value("role", "viewer"));
        }
    }
    return ProjectRole::None;
}

bool AccessControl::allowed(const AuthContext& ctx, const std::string& project_id, Action action) {
    const ProjectRole role = roleIn(ctx, project_id);
    switch (action) {
        case Action::Read:
            return role != ProjectRole::None;
        case Action::Run:
            // A viewer may watch but not start. Running a workflow sends email,
            // writes to collections and spends money at an API - it is not a
            // read however little it changes the workflow itself.
            return role == ProjectRole::Editor || role == ProjectRole::Admin;
        case Action::Write:
            return role == ProjectRole::Editor || role == ProjectRole::Admin;
        case Action::Manage:
            return role == ProjectRole::Admin;
    }
    return false;
}

common::Result<std::string> AccessControl::personalProjectFor(const std::string& user_id) {
    storage::QueryOptions options;
    options.page_size = 1000;
    options.filters.push_back({"type", "personal"});

    auto result = storage_.query(PROJECTS, options);
    if (result.failed()) return Error(ErrorCode::DatabaseError, result.error().message());

    for (const auto& project : result.value().documents) {
        if (project.value("ownerId", "") == user_id) {
            return project.value("_id", std::string());
        }
    }
    return Error(ErrorCode::NotFound, "No personal project for user " + user_id);
}

common::Result<nlohmann::json> AccessControl::ensurePersonalProject(const std::string& user_id,
                                                                    const std::string& username) {
    auto existing = personalProjectFor(user_id);
    if (existing.ok()) {
        auto project = storage_.get(PROJECTS, existing.value());
        if (project.ok()) return project.value();
    }

    const std::string id = "prj_" + UUID::generate();
    nlohmann::json project = {
        {"name", username.empty() ? std::string("Personal") : username + "'s project"},
        {"type", "personal"},
        {"ownerId", user_id},
        {"members", nlohmann::json::array()},
        {"createdAt", TimeUtils::nowMs()},
    };

    auto inserted = storage_.insert(PROJECTS, project, id);
    if (inserted.failed()) {
        return Error(ErrorCode::DatabaseError, inserted.error().message());
    }
    project["_id"] = id;
    LOG_INFO("Created personal project {} for user {}", id, user_id);
    return project;
}

} // namespace smartbotic::webserver::auth