#include "dialogs/BlackholeResolveDialog.h"

#include <QDialogButtonBox>
#include <QFrame>
#include <QLabel>
#include <QPushButton>
#include <QStackedWidget>
#include <QVBoxLayout>

namespace {

QPushButton* makeAlgoButton(const QString& title, const QString& subtitle, QWidget* parent) {
    auto* btn = new QPushButton(parent);
    btn->setCheckable(false);
    btn->setCursor(Qt::PointingHandCursor);
    btn->setMinimumHeight(86);
    btn->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Fixed);
    btn->setText(title + QStringLiteral("\n") + subtitle);
    btn->setStyleSheet(
        "QPushButton { text-align: left; padding: 10px 12px; border: 1px solid palette(mid); border-radius: 8px; }"
        "QPushButton:hover { border-color: palette(highlight); }");
    return btn;
}

}  // namespace

BlackholeResolveDialog::BlackholeResolveDialog(const QString& blackholeName, QWidget* parent)
    : QDialog(parent),
      m_blackholeName(blackholeName) {
    setModal(true);
    setMinimumSize(560, 420);
    setWindowTitle(QStringLiteral("黑洞解决"));

    auto* root = new QVBoxLayout(this);
    m_pages = new QStackedWidget(this);
    root->addWidget(m_pages, 1);

    buildSelectPage();
    buildDetailPage();
    m_pages->setCurrentWidget(m_pageSelect);
}

void BlackholeResolveDialog::buildSelectPage() {
    m_pageSelect = new QWidget(this);
    auto* layout = new QVBoxLayout(m_pageSelect);
    layout->setContentsMargins(8, 8, 8, 8);
    layout->setSpacing(12);

    auto* title = new QLabel(QStringLiteral("第 1 步：选择黑洞解决算法"), m_pageSelect);
    auto* sub = new QLabel(QStringLiteral("当前黑洞：%1").arg(m_blackholeName), m_pageSelect);
    title->setStyleSheet("font-size: 18px; font-weight: 600;");
    sub->setStyleSheet("color: palette(mid);");
    layout->addWidget(title);
    layout->addWidget(sub);

    auto* btnCopy = makeAlgoButton(
        QStringLiteral("复制背景其他区域"),
        QStringLiteral("进入画布拖动取样框，直观选择复制来源。"),
        m_pageSelect);
    auto* btnOriginal = makeAlgoButton(
        QStringLiteral("使用原始背景"),
        QStringLiteral("撤销黑洞显示，恢复抠图前背景区域。"),
        m_pageSelect);
    layout->addWidget(btnCopy);
    layout->addWidget(btnOriginal);

    auto* modelNote = new QLabel(
        QStringLiteral("模型补全：已预留接口，本版本暂不实现。"),
        m_pageSelect);
    modelNote->setStyleSheet("color: palette(mid);");
    layout->addWidget(modelNote);
    layout->addStretch(1);

    auto* btns = new QDialogButtonBox(QDialogButtonBox::Cancel, m_pageSelect);
    connect(btns, &QDialogButtonBox::rejected, this, &QDialog::reject);
    layout->addWidget(btns);

    connect(btnCopy, &QPushButton::clicked, this, [this]() {
        enterAlgorithmPage(Algorithm::CopyBackgroundRegion);
    });
    connect(btnOriginal, &QPushButton::clicked, this, [this]() {
        enterAlgorithmPage(Algorithm::UseOriginalBackground);
    });

    m_pages->addWidget(m_pageSelect);
}

void BlackholeResolveDialog::buildDetailPage() {
    m_pageDetail = new QWidget(this);
    auto* layout = new QVBoxLayout(m_pageDetail);
    layout->setContentsMargins(8, 8, 8, 8);
    layout->setSpacing(10);

    m_detailTitle = new QLabel(m_pageDetail);
    m_detailTitle->setStyleSheet("font-size: 18px; font-weight: 600;");
    m_detailHint = new QLabel(m_pageDetail);
    m_detailHint->setWordWrap(true);
    m_detailHint->setStyleSheet("color: palette(mid);");
    layout->addWidget(m_detailTitle);
    layout->addWidget(m_detailHint);

    m_algoDetails = new QStackedWidget(m_pageDetail);

    // 详情页 A：复制背景其他区域（交互布局）
    m_copyDetail = new QWidget(m_algoDetails);
    {
        auto* cLay = new QVBoxLayout(m_copyDetail);
        cLay->setSpacing(8);

        auto* panel = new QFrame(m_copyDetail);
        panel->setFrameShape(QFrame::StyledPanel);
        auto* pLay = new QVBoxLayout(panel);
        pLay->setSpacing(8);

        auto* tip = new QLabel(
            QStringLiteral("说明：点击“应用”后进入画布拖动模式。\n在画布中拖动青色取样框，松开鼠标即可将该区域复制到黑洞位置并自动移除黑洞。"),
            panel);
        tip->setWordWrap(true);
        tip->setStyleSheet("color: palette(mid);");
        pLay->addWidget(tip);
        cLay->addWidget(panel);
        cLay->addStretch(1);
    }

    // 详情页 B：使用原始背景（确认布局）
    m_originalDetail = new QWidget(m_algoDetails);
    {
        auto* oLay = new QVBoxLayout(m_originalDetail);
        oLay->setSpacing(8);
        auto* desc = new QLabel(
            QStringLiteral("该方案不会改动背景像素文件，只会将黑洞切换为不显示，从而恢复原始背景区域。"),
            m_originalDetail);
        desc->setWordWrap(true);
        auto* note = new QLabel(
            QStringLiteral("适用场景：当前黑洞区域无需二次修补，只需恢复抠图前背景；应用后黑洞会自动移除。"),
            m_originalDetail);
        note->setWordWrap(true);
        note->setStyleSheet("color: palette(mid);");
        oLay->addWidget(desc);
        oLay->addWidget(note);
        oLay->addStretch(1);
    }

    m_algoDetails->addWidget(m_copyDetail);
    m_algoDetails->addWidget(m_originalDetail);
    layout->addWidget(m_algoDetails, 1);

    auto* btns = new QDialogButtonBox(m_pageDetail);
    auto* btnBack = btns->addButton(QStringLiteral("上一步"), QDialogButtonBox::ActionRole);
    auto* btnApply = btns->addButton(QStringLiteral("应用"), QDialogButtonBox::AcceptRole);
    auto* btnCancel = btns->addButton(QDialogButtonBox::Cancel);
    connect(btnBack, &QPushButton::clicked, this, [this]() {
        m_pages->setCurrentWidget(m_pageSelect);
    });
    connect(btnApply, &QPushButton::clicked, this, &QDialog::accept);
    connect(btnCancel, &QPushButton::clicked, this, &QDialog::reject);
    layout->addWidget(btns);

    m_pages->addWidget(m_pageDetail);
}

void BlackholeResolveDialog::enterAlgorithmPage(Algorithm algo) {
    m_selectedAlgorithm = algo;
    if (algo == Algorithm::CopyBackgroundRegion) {
        m_detailTitle->setText(QStringLiteral("第 2 步：复制背景其他区域"));
        m_detailHint->setText(QStringLiteral("准备进入画布拖动取样框模式。"));
        m_algoDetails->setCurrentWidget(m_copyDetail);
    } else {
        m_detailTitle->setText(QStringLiteral("第 2 步：使用原始背景"));
        m_detailHint->setText(QStringLiteral("确认后将切换为原始背景显示。"));
        m_algoDetails->setCurrentWidget(m_originalDetail);
    }
    m_pages->setCurrentWidget(m_pageDetail);
}