// SPDX-FileCopyrightText: 2023 Mathis Brüchert <mbb@kaidan.im>
// SPDX-FileCopyrightText: 2023 Carl Schwan <carl@carlschwan.eu>
// SPDX-FileCopyrightText: 2023 ivan tkachenko <me@ratijas.tk>
//
// SPDX-License-Identifier: LGPL-2.0-only OR LGPL-3.0-only OR LicenseRef-KDE-Accepted-LGPL

import QtQuick 2.15
import QtQuick.Layouts 1.15
import QtQuick.Controls 2.15 as QQC2
import QtQuick.Templates 2.15 as T
import org.kde.kirigami 2.20 as Kirigami

/**
 * This component is a button that can be displayed at the bottom of a page.
 *
 * @code{.qml}
 * import QtQuick 2.15
 * import QtQuick.Controls 2.15 as QQC2
 * import org.kde.kirigami 2.20 as Kirigami
 * import org.kde.kirigamiaddons.components 1.0 as KirigamiComponents
 *
 * Kirigami.ScrollablePage {
 *     ListView {
 *         model: []
 *         delegate: QQC2.ItemDelegate {}
 *
 *         KirigamiComponents.FloatingButton {
 *             anchors {
 *                 right: parent.right
 *                 bottom: parent.bottom
 *             }
 *             margins: Kirigami.Units.largeSpacing
 *
 *             action: Kirigami.Action {
 *                 text: "Add new item"
 *                 icon.name: "list-add"
 *             }
 *         }
 *     }
 * }
 * @endcode
 *
 * @since Kirigami Addons 0.11
 */
T.RoundButton {
    id: controlRoot

    Kirigami.Theme.colorSet: Kirigami.Theme.Button
    Kirigami.Theme.inherit: false

    implicitWidth: Math.max(implicitBackgroundWidth + leftInset + rightInset,
                            implicitContentWidth + leftPadding + rightPadding)
    implicitHeight: Math.max(implicitBackgroundHeight + topInset + bottomInset,
                             implicitContentHeight + topPadding + bottomPadding)

    readonly property size __effectiveIconSize: Qt.size(
        icon.height > 0 ? icon.height : Kirigami.Units.iconSizes.medium,
        icon.width > 0 ? icon.width : Kirigami.Units.iconSizes.medium,
    )

    // Property is needed to prevent binding loops on insets
    readonly property real __padding: radius === Infinity
        ? Math.round(Math.max(__effectiveIconSize.width, __effectiveIconSize.height) * (Math.sqrt(2) - 1))
        : Kirigami.Settings.hasTransientTouchInput ? (Kirigami.Units.largeSpacing * 2) : Kirigami.Units.largeSpacing

    // Extra clickable area that adjusts both paddings and insets.
    property real margins: 0
    property real topMargin: margins
    property real leftMargin: margins
    property real rightMargin: margins
    property real bottomMargin: margins

    // Fit icon into a square bounded by a circle bounded by button
    padding: __padding

    topPadding: padding + topMargin
    leftPadding: padding + leftMargin
    rightPadding: padding + rightMargin
    bottomPadding: padding + bottomMargin

    // If user overrides individual padding value, we should adjust background. By default all insets will be 0.
    topInset: topMargin
    leftInset: leftMargin
    rightInset: rightMargin
    bottomInset: bottomMargin

    // Set to Infinity to get extra padding for round button style.
    radius: Kirigami.Units.cornerRadius

    // Text is not supported anyway
    spacing: 0

    hoverEnabled: !Kirigami.Settings.hasTransientTouchInput

    contentItem: Item {
        implicitWidth: controlRoot.__effectiveIconSize.width
        implicitHeight: controlRoot.__effectiveIconSize.height

        Kirigami.Icon {
            anchors.fill: parent
            color: controlRoot.icon.color
            source: controlRoot.icon.name !== "" ? controlRoot.icon.name : controlRoot.icon.source
        }
    }

    background: Item {
        Kirigami.ShadowedRectangle {
            anchors.centerIn: parent
            width: Math.min(parent.width, parent.height)
            height: width
            radius: controlRoot.radius

            shadow {
                size: 10
                xOffset: 0
                yOffset: 2
                color: Qt.rgba(0, 0, 0, 0.2)
            }

            border {
                width: 1
                color: if (controlRoot.down || controlRoot.visualFocus) {
                    Kirigami.ColorUtils.tintWithAlpha(Kirigami.Theme.hoverColor, Kirigami.Theme.backgroundColor, 0.4)
                } else if (controlRoot.enabled && controlRoot.hovered) {
                    Kirigami.ColorUtils.tintWithAlpha(Kirigami.Theme.hoverColor, Kirigami.Theme.backgroundColor, 0.6)
                } else {
                    Kirigami.ColorUtils.linearInterpolation(Kirigami.Theme.backgroundColor, Kirigami.Theme.textColor, Kirigami.Theme.frameContrast)
                }
            }

            color: if (controlRoot.down || controlRoot.visualFocus) {
                Kirigami.ColorUtils.tintWithAlpha(Kirigami.Theme.hoverColor, Kirigami.Theme.backgroundColor, 0.6)
            } else if (controlRoot.enabled && controlRoot.hovered) {
                Kirigami.ColorUtils.tintWithAlpha(Kirigami.Theme.hoverColor, Kirigami.Theme.backgroundColor, 0.8)
            } else {
                Kirigami.Theme.backgroundColor
            }

            Behavior on border.color {
                ColorAnimation {
                    duration: Kirigami.Units.veryShortDuration
                }
            }

            Behavior on color {
                ColorAnimation {
                    duration: Kirigami.Units.veryShortDuration
                }
            }
        }
    }
}