//
// LogPanel.cpp：运行时日志面板实现。
//
// 数据源 = Engine::Debug::LogRing（spdlog ring sink 落的整行）。
// 级别着色（trace 灰 / debug 青 / info 浅白 / warn 黄 / error 红 /
// fatal 亮红带背景条）+ 级别过滤 + 文本过滤 + Auto-scroll（滚动条
// 贴底才自动拉，上翻看历史不被拽回）。
//

#include "LogPanel.h"

#include <Engine/Core/LogRing.h>

#include <imgui.h>

#include <cctype>
#include <cstring>
#include <string>

void LogPanel::Draw(const EditorContext& ctx)
{
    (void)ctx;
    if (!ImGui::Begin("Log"))
    {
        ImGui::End();
        return;
    }

    // ---- 工具栏：清空 / 自动滚动 / 文本过滤 / 级别过滤 ----
    if (ImGui::Button("Clear"))
    {
        Engine::Debug::LogRing().Clear();
    }
    ImGui::SameLine();
    ImGui::Checkbox("Auto-scroll", &m_AutoScroll);
    ImGui::SameLine();
    ImGui::SetNextItemWidth(160.0f);
    ImGui::InputTextWithHint("##filter", "filter...", m_Filter, sizeof(m_Filter));
    ImGui::SameLine();
    ImGui::Checkbox("Trace", &m_ShowTrace);
    ImGui::SameLine();
    ImGui::Checkbox("Info", &m_ShowInfo);
    ImGui::SameLine();
    ImGui::Checkbox("Warn", &m_ShowWarn);
    ImGui::SameLine();
    ImGui::Checkbox("Error", &m_ShowError);
    ImGui::Separator();

    // ---- 版本感知：有新日志且滚动条贴底 → 拉底（上翻历史不拽回）----
    const Engine::u64 ver = Engine::Debug::LogRing().Version();
    bool scrollToBottom = false;
    if (ver != m_LastVersion)
    {
        m_LastVersion = ver;
        if (m_AutoScroll)
        {
            scrollToBottom = ImGui::GetScrollY() >=
                             ImGui::GetScrollMaxY() - 24.0f;
        }
    }

    if (ImGui::BeginChild("loglist", {0.0f, 0.0f}, false,
                          ImGuiWindowFlags_HorizontalScrollbar))
    {
        const auto entries = Engine::Debug::LogRing().Snapshot();
        for (const auto& e : entries)
        {
            using lv = spdlog::level::level_enum;
            bool show = false;
            switch (e.level)
            {
                case lv::trace:
                case lv::debug: show = m_ShowTrace; break;
                case lv::info:  show = m_ShowInfo; break;
                case lv::warn:  show = m_ShowWarn; break;
                case lv::err:
                case lv::critical: show = m_ShowError; break;
                default: show = m_ShowInfo; break;
            }
            if (!show) continue;
            if (m_Filter[0] != '\0')
            {
                // 简单子串过滤（大小写不敏感）
                std::string lower;
                lower.reserve(e.msg.size());
                for (char c : e.msg)
                {
                    lower.push_back(static_cast<char>(
                        std::tolower(static_cast<unsigned char>(c))));
                }
                std::string needle;
                needle.reserve(strlen(m_Filter));
                for (const char* p = m_Filter; *p; ++p)
                {
                    needle.push_back(static_cast<char>(
                        std::tolower(static_cast<unsigned char>(*p))));
                }
                if (lower.find(needle) == std::string::npos)
                {
                    continue;
                }
            }

            // ---- 渲染：级别徽标（恒彩色，固定列）+ 消息本体 ----
            // 消息色只有 warn/error/fatal 染色（info 白是惯例），颜色
            // 辨识主要靠徽标列——UE Output Log 的 Verbosity 列同位
            ImVec4 tagCol, msgCol;
            const char* tag = "INFO";
            bool bg = false;
            switch (e.level)
            {
                case lv::trace:
                    tag = "TRACE"; tagCol = {0.55f, 0.55f, 0.55f, 1.0f};
                    msgCol = {0.55f, 0.55f, 0.55f, 1.0f}; break;
                case lv::debug:
                    tag = "DEBUG"; tagCol = {0.40f, 0.80f, 0.90f, 1.0f};
                    msgCol = {0.70f, 0.70f, 0.70f, 1.0f}; break;
                case lv::info:
                    tag = "INFO";  tagCol = {0.45f, 0.72f, 0.95f, 1.0f};
                    msgCol = {0.90f, 0.90f, 0.90f, 1.0f}; break;
                case lv::warn:
                    tag = "WARN";  tagCol = {1.00f, 0.78f, 0.20f, 1.0f};
                    msgCol = {1.00f, 0.78f, 0.20f, 1.0f}; break;
                case lv::err:
                    tag = "ERROR"; tagCol = {1.00f, 0.35f, 0.35f, 1.0f};
                    msgCol = {1.00f, 0.35f, 0.35f, 1.0f}; break;
                default:
                    tag = "FATAL"; tagCol = {1.00f, 0.15f, 0.15f, 1.0f};
                    msgCol = {1.00f, 0.15f, 0.15f, 1.0f};
                    bg = true; break;
            }
            if (bg)
            {
                // fatal：整行暗红背景条提级（先画背景再画文本）
                const ImVec2 p0 = ImGui::GetCursorScreenPos();
                const ImVec2 p1(p0.x + ImGui::GetContentRegionAvail().x,
                                p0.y + ImGui::GetTextLineHeight());
                ImGui::GetWindowDrawList()->AddRectFilled(
                    p0, p1, IM_COL32(90, 10, 10, 160));
            }
            ImGui::TextColored(tagCol, "%s", tag);
            ImGui::SameLine(40.0f);   // 徽标固定列宽，消息对齐成两列
            ImGui::TextColored(msgCol, "%s", e.msg.c_str());
        }
        if (scrollToBottom)
        {
            ImGui::SetScrollHereY(1.0f);
        }
    }
    ImGui::EndChild();
    ImGui::End();
}