/*
 * Copyright (C) 2013 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.widget;

import static android.view.View.IMPORTANT_FOR_ACCESSIBILITY_AUTO;
import static android.view.View.IMPORTANT_FOR_ACCESSIBILITY_YES;

import android.annotation.TestApi;
import android.content.Context;
import android.content.res.TypedArray;
import android.os.Parcelable;
import android.text.format.DateFormat;
import android.text.format.DateUtils;
import android.util.AttributeSet;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.accessibility.AccessibilityEvent;
import android.view.inputmethod.EditorInfo;
import android.view.inputmethod.InputMethodManager;

import com.android.internal.R;

import libcore.icu.LocaleData;

import java.util.Calendar;

A delegate implementing the basic spinner-based TimePicker.
/**
 * A delegate implementing the basic spinner-based TimePicker.
 */
class TimePickerSpinnerDelegate extends TimePicker.AbstractTimePickerDelegate {
    private static final boolean DEFAULT_ENABLED_STATE = true;
    private static final int HOURS_IN_HALF_DAY = 12;

    private final NumberPicker mHourSpinner;
    private final NumberPicker mMinuteSpinner;
    private final NumberPicker mAmPmSpinner;
    private final EditText mHourSpinnerInput;
    private final EditText mMinuteSpinnerInput;
    private final EditText mAmPmSpinnerInput;
    private final TextView mDivider;

    // Note that the legacy implementation of the TimePicker is
    // using a button for toggling between AM/PM while the new
    // version uses a NumberPicker spinner. Therefore the code
    // accommodates these two cases to be backwards compatible.
    private final Button mAmPmButton;

    private final String[] mAmPmStrings;

    private final Calendar mTempCalendar;

    private boolean mIsEnabled = DEFAULT_ENABLED_STATE;
    private boolean mHourWithTwoDigit;
    private char mHourFormat;

    private boolean mIs24HourView;
    private boolean mIsAm;

    public TimePickerSpinnerDelegate(TimePicker delegator, Context context, AttributeSet attrs,
            int defStyleAttr, int defStyleRes) {
        super(delegator, context);

        // process style attributes
        final TypedArray a = mContext.obtainStyledAttributes(
                attrs, R.styleable.TimePicker, defStyleAttr, defStyleRes);
        final int layoutResourceId = a.getResourceId(
                R.styleable.TimePicker_legacyLayout, R.layout.time_picker_legacy);
        a.recycle();

        final LayoutInflater inflater = LayoutInflater.from(mContext);
        final View view = inflater.inflate(layoutResourceId, mDelegator, true);
        view.setSaveFromParentEnabled(false);

        // hour
        mHourSpinner = delegator.findViewById(R.id.hour);
        mHourSpinner.setOnValueChangedListener(new NumberPicker.OnValueChangeListener() {
            public void onValueChange(NumberPicker spinner, int oldVal, int newVal) {
                updateInputState();
                if (!is24Hour()) {
                    if ((oldVal == HOURS_IN_HALF_DAY - 1 && newVal == HOURS_IN_HALF_DAY) ||
                            (oldVal == HOURS_IN_HALF_DAY && newVal == HOURS_IN_HALF_DAY - 1)) {
                        mIsAm = !mIsAm;
                        updateAmPmControl();
                    }
                }
                onTimeChanged();
            }
        });
        mHourSpinnerInput = mHourSpinner.findViewById(R.id.numberpicker_input);
        mHourSpinnerInput.setImeOptions(EditorInfo.IME_ACTION_NEXT);

        // divider (only for the new widget style)
        mDivider = mDelegator.findViewById(R.id.divider);
        if (mDivider != null) {
            setDividerText();
        }

        // minute
        mMinuteSpinner = mDelegator.findViewById(R.id.minute);
        mMinuteSpinner.setMinValue(0);
        mMinuteSpinner.setMaxValue(59);
        mMinuteSpinner.setOnLongPressUpdateInterval(100);
        mMinuteSpinner.setFormatter(NumberPicker.getTwoDigitFormatter());
        mMinuteSpinner.setOnValueChangedListener(new NumberPicker.OnValueChangeListener() {
            public void onValueChange(NumberPicker spinner, int oldVal, int newVal) {
                updateInputState();
                int minValue = mMinuteSpinner.getMinValue();
                int maxValue = mMinuteSpinner.getMaxValue();
                if (oldVal == maxValue && newVal == minValue) {
                    int newHour = mHourSpinner.getValue() + 1;
                    if (!is24Hour() && newHour == HOURS_IN_HALF_DAY) {
                        mIsAm = !mIsAm;
                        updateAmPmControl();
                    }
                    mHourSpinner.setValue(newHour);
                } else if (oldVal == minValue && newVal == maxValue) {
                    int newHour = mHourSpinner.getValue() - 1;
                    if (!is24Hour() && newHour == HOURS_IN_HALF_DAY - 1) {
                        mIsAm = !mIsAm;
                        updateAmPmControl();
                    }
                    mHourSpinner.setValue(newHour);
                }
                onTimeChanged();
            }
        });
        mMinuteSpinnerInput = mMinuteSpinner.findViewById(R.id.numberpicker_input);
        mMinuteSpinnerInput.setImeOptions(EditorInfo.IME_ACTION_NEXT);

        // Get the localized am/pm strings and use them in the spinner.
        mAmPmStrings = getAmPmStrings(context);

        // am/pm
        final View amPmView = mDelegator.findViewById(R.id.amPm);
        if (amPmView instanceof Button) {
            mAmPmSpinner = null;
            mAmPmSpinnerInput = null;
            mAmPmButton = (Button) amPmView;
            mAmPmButton.setOnClickListener(new View.OnClickListener() {
                public void onClick(View button) {
                    button.requestFocus();
                    mIsAm = !mIsAm;
                    updateAmPmControl();
                    onTimeChanged();
                }
            });
        } else {
            mAmPmButton = null;
            mAmPmSpinner = (NumberPicker) amPmView;
            mAmPmSpinner.setMinValue(0);
            mAmPmSpinner.setMaxValue(1);
            mAmPmSpinner.setDisplayedValues(mAmPmStrings);
            mAmPmSpinner.setOnValueChangedListener(new NumberPicker.OnValueChangeListener() {
                public void onValueChange(NumberPicker picker, int oldVal, int newVal) {
                    updateInputState();
                    picker.requestFocus();
                    mIsAm = !mIsAm;
                    updateAmPmControl();
                    onTimeChanged();
                }
            });
            mAmPmSpinnerInput = mAmPmSpinner.findViewById(R.id.numberpicker_input);
            mAmPmSpinnerInput.setImeOptions(EditorInfo.IME_ACTION_DONE);
        }

        if (isAmPmAtStart()) {
            // Move the am/pm view to the beginning
            ViewGroup amPmParent = delegator.findViewById(R.id.timePickerLayout);
            amPmParent.removeView(amPmView);
            amPmParent.addView(amPmView, 0);
            // Swap layout margins if needed. They may be not symmetrical (Old Standard Theme
            // for example and not for Holo Theme)
            ViewGroup.MarginLayoutParams lp =
                    (ViewGroup.MarginLayoutParams) amPmView.getLayoutParams();
            final int startMargin = lp.getMarginStart();
            final int endMargin = lp.getMarginEnd();
            if (startMargin != endMargin) {
                lp.setMarginStart(endMargin);
                lp.setMarginEnd(startMargin);
            }
        }

        getHourFormatData();

        // update controls to initial state
        updateHourControl();
        updateMinuteControl();
        updateAmPmControl();

        // set to current time
        mTempCalendar = Calendar.getInstance(mLocale);
        setHour(mTempCalendar.get(Calendar.HOUR_OF_DAY));
        setMinute(mTempCalendar.get(Calendar.MINUTE));

        if (!isEnabled()) {
            setEnabled(false);
        }

        // set the content descriptions
        setContentDescriptions();

        // If not explicitly specified this view is important for accessibility.
        if (mDelegator.getImportantForAccessibility() == IMPORTANT_FOR_ACCESSIBILITY_AUTO) {
            mDelegator.setImportantForAccessibility(IMPORTANT_FOR_ACCESSIBILITY_YES);
        }
    }

    @Override
    public boolean validateInput() {
        return true;
    }

    private void getHourFormatData() {
        final String bestDateTimePattern = DateFormat.getBestDateTimePattern(mLocale,
                (mIs24HourView) ? "Hm" : "hm");
        final int lengthPattern = bestDateTimePattern.length();
        mHourWithTwoDigit = false;
        char hourFormat = '\0';
        // Check if the returned pattern is single or double 'H', 'h', 'K', 'k'. We also save
        // the hour format that we found.
        for (int i = 0; i < lengthPattern; i++) {
            final char c = bestDateTimePattern.charAt(i);
            if (c == 'H' || c == 'h' || c == 'K' || c == 'k') {
                mHourFormat = c;
                if (i + 1 < lengthPattern && c == bestDateTimePattern.charAt(i + 1)) {
                    mHourWithTwoDigit = true;
                }
                break;
            }
        }
    }

    private boolean isAmPmAtStart() {
        final String bestDateTimePattern = DateFormat.getBestDateTimePattern(mLocale,
                "hm" /* skeleton */);

        return bestDateTimePattern.startsWith("a");
    }

    
The time separator is defined in the Unicode CLDR and cannot be supposed to be ":".
See http://unicode.org/cldr/trac/browser/trunk/common/main
We pass the correct "skeleton" depending on 12 or 24 hours view and then extract the
separator as the character which is just after the hour marker in the returned pattern.
/**
     * The time separator is defined in the Unicode CLDR and cannot be supposed to be ":".
     *
     * See http://unicode.org/cldr/trac/browser/trunk/common/main
     *
     * We pass the correct "skeleton" depending on 12 or 24 hours view and then extract the
     * separator as the character which is just after the hour marker in the returned pattern.
     */
    private void setDividerText() {
        final String skeleton = (mIs24HourView) ? "Hm" : "hm";
        final String bestDateTimePattern = DateFormat.getBestDateTimePattern(mLocale,
                skeleton);
        final String separatorText;
        int hourIndex = bestDateTimePattern.lastIndexOf('H');
        if (hourIndex == -1) {
            hourIndex = bestDateTimePattern.lastIndexOf('h');
        }
        if (hourIndex == -1) {
            // Default case
            separatorText = ":";
        } else {
            int minuteIndex = bestDateTimePattern.indexOf('m', hourIndex + 1);
            if  (minuteIndex == -1) {
                separatorText = Character.toString(bestDateTimePattern.charAt(hourIndex + 1));
            } else {
                separatorText = bestDateTimePattern.substring(hourIndex + 1, minuteIndex);
            }
        }
        mDivider.setText(separatorText);
    }

    @Override
    public void setDate(int hour, int minute) {
        setCurrentHour(hour, false);
        setCurrentMinute(minute, false);

        onTimeChanged();
    }

    @Override
    public void setHour(int hour) {
        setCurrentHour(hour, true);
    }

    private void setCurrentHour(int currentHour, boolean notifyTimeChanged) {
        // why was Integer used in the first place?
        if (currentHour == getHour()) {
            return;
        }
        resetAutofilledValue();
        if (!is24Hour()) {
            // convert [0,23] ordinal to wall clock display
            if (currentHour >= HOURS_IN_HALF_DAY) {
                mIsAm = false;
                if (currentHour > HOURS_IN_HALF_DAY) {
                    currentHour = currentHour - HOURS_IN_HALF_DAY;
                }
            } else {
                mIsAm = true;
                if (currentHour == 0) {
                    currentHour = HOURS_IN_HALF_DAY;
                }
            }
            updateAmPmControl();
        }
        mHourSpinner.setValue(currentHour);
        if (notifyTimeChanged) {
            onTimeChanged();
        }
    }

    @Override
    public int getHour() {
        int currentHour = mHourSpinner.getValue();
        if (is24Hour()) {
            return currentHour;
        } else if (mIsAm) {
            return currentHour % HOURS_IN_HALF_DAY;
        } else {
            return (currentHour % HOURS_IN_HALF_DAY) + HOURS_IN_HALF_DAY;
        }
    }

    @Override
    public void setMinute(int minute) {
        setCurrentMinute(minute, true);
    }

    private void setCurrentMinute(int minute, boolean notifyTimeChanged) {
        if (minute == getMinute()) {
            return;
        }
        resetAutofilledValue();
        mMinuteSpinner.setValue(minute);
        if (notifyTimeChanged) {
            onTimeChanged();
        }
    }

    @Override
    public int getMinute() {
        return mMinuteSpinner.getValue();
    }

    public void setIs24Hour(boolean is24Hour) {
        if (mIs24HourView == is24Hour) {
            return;
        }
        // cache the current hour since spinner range changes and BEFORE changing mIs24HourView!!
        int currentHour = getHour();
        // Order is important here.
        mIs24HourView = is24Hour;
        getHourFormatData();
        updateHourControl();
        // set value after spinner range is updated
        setCurrentHour(currentHour, false);
        updateMinuteControl();
        updateAmPmControl();
    }

    @Override
    public boolean is24Hour() {
        return mIs24HourView;
    }

    @Override
    public void setEnabled(boolean enabled) {
        mMinuteSpinner.setEnabled(enabled);
        if (mDivider != null) {
            mDivider.setEnabled(enabled);
        }
        mHourSpinner.setEnabled(enabled);
        if (mAmPmSpinner != null) {
            mAmPmSpinner.setEnabled(enabled);
        } else {
            mAmPmButton.setEnabled(enabled);
        }
        mIsEnabled = enabled;
    }

    @Override
    public boolean isEnabled() {
        return mIsEnabled;
    }

    @Override
    public int getBaseline() {
        return mHourSpinner.getBaseline();
    }

    @Override
    public Parcelable onSaveInstanceState(Parcelable superState) {
        return new SavedState(superState, getHour(), getMinute(), is24Hour());
    }

    @Override
    public void onRestoreInstanceState(Parcelable state) {
        if (state instanceof SavedState) {
            final SavedState ss = (SavedState) state;
            setHour(ss.getHour());
            setMinute(ss.getMinute());
        }
    }

    @Override
    public boolean dispatchPopulateAccessibilityEvent(AccessibilityEvent event) {
        onPopulateAccessibilityEvent(event);
        return true;
    }

    @Override
    public void onPopulateAccessibilityEvent(AccessibilityEvent event) {
        int flags = DateUtils.FORMAT_SHOW_TIME;
        if (mIs24HourView) {
            flags |= DateUtils.FORMAT_24HOUR;
        } else {
            flags |= DateUtils.FORMAT_12HOUR;
        }
        mTempCalendar.set(Calendar.HOUR_OF_DAY, getHour());
        mTempCalendar.set(Calendar.MINUTE, getMinute());
        String selectedDateUtterance = DateUtils.formatDateTime(mContext,
                mTempCalendar.getTimeInMillis(), flags);
        event.getText().add(selectedDateUtterance);
    }

    
@hide
/** @hide */
    @Override
    @TestApi
    public View getHourView() {
        return mHourSpinnerInput;
    }

    
@hide
/** @hide */
    @Override
    @TestApi
    public View getMinuteView() {
        return mMinuteSpinnerInput;
    }

    
@hide
/** @hide */
    @Override
    @TestApi
    public View getAmView() {
        return mAmPmSpinnerInput;
    }

    
@hide
/** @hide */
    @Override
    @TestApi
    public View getPmView() {
        return mAmPmSpinnerInput;
    }

    private void updateInputState() {
        // Make sure that if the user changes the value and the IME is active
        // for one of the inputs if this widget, the IME is closed. If the user
        // changed the value via the IME and there is a next input the IME will
        // be shown, otherwise the user chose another means of changing the
        // value and having the IME up makes no sense.
        InputMethodManager inputMethodManager = InputMethodManager.peekInstance();
        if (inputMethodManager != null) {
            if (inputMethodManager.isActive(mHourSpinnerInput)) {
                mHourSpinnerInput.clearFocus();
                inputMethodManager.hideSoftInputFromWindow(mDelegator.getWindowToken(), 0);
            } else if (inputMethodManager.isActive(mMinuteSpinnerInput)) {
                mMinuteSpinnerInput.clearFocus();
                inputMethodManager.hideSoftInputFromWindow(mDelegator.getWindowToken(), 0);
            } else if (inputMethodManager.isActive(mAmPmSpinnerInput)) {
                mAmPmSpinnerInput.clearFocus();
                inputMethodManager.hideSoftInputFromWindow(mDelegator.getWindowToken(), 0);
            }
        }
    }

    private void updateAmPmControl() {
        if (is24Hour()) {
            if (mAmPmSpinner != null) {
                mAmPmSpinner.setVisibility(View.GONE);
            } else {
                mAmPmButton.setVisibility(View.GONE);
            }
        } else {
            int index = mIsAm ? Calendar.AM : Calendar.PM;
            if (mAmPmSpinner != null) {
                mAmPmSpinner.setValue(index);
                mAmPmSpinner.setVisibility(View.VISIBLE);
            } else {
                mAmPmButton.setText(mAmPmStrings[index]);
                mAmPmButton.setVisibility(View.VISIBLE);
            }
        }
        mDelegator.sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_SELECTED);
    }

    private void onTimeChanged() {
        mDelegator.sendAccessibilityEvent(AccessibilityEvent.TYPE_VIEW_SELECTED);
        if (mOnTimeChangedListener != null) {
            mOnTimeChangedListener.onTimeChanged(mDelegator, getHour(),
                    getMinute());
        }
        if (mAutoFillChangeListener != null) {
            mAutoFillChangeListener.onTimeChanged(mDelegator, getHour(), getMinute());
        }
    }

    private void updateHourControl() {
        if (is24Hour()) {
            // 'k' means 1-24 hour
            if (mHourFormat == 'k') {
                mHourSpinner.setMinValue(1);
                mHourSpinner.setMaxValue(24);
            } else {
                mHourSpinner.setMinValue(0);
                mHourSpinner.setMaxValue(23);
            }
        } else {
            // 'K' means 0-11 hour
            if (mHourFormat == 'K') {
                mHourSpinner.setMinValue(0);
                mHourSpinner.setMaxValue(11);
            } else {
                mHourSpinner.setMinValue(1);
                mHourSpinner.setMaxValue(12);
            }
        }
        mHourSpinner.setFormatter(mHourWithTwoDigit ? NumberPicker.getTwoDigitFormatter() : null);
    }

    private void updateMinuteControl() {
        if (is24Hour()) {
            mMinuteSpinnerInput.setImeOptions(EditorInfo.IME_ACTION_DONE);
        } else {
            mMinuteSpinnerInput.setImeOptions(EditorInfo.IME_ACTION_NEXT);
        }
    }

    private void setContentDescriptions() {
        // Minute
        trySetContentDescription(mMinuteSpinner, R.id.increment,
                R.string.time_picker_increment_minute_button);
        trySetContentDescription(mMinuteSpinner, R.id.decrement,
                R.string.time_picker_decrement_minute_button);
        // Hour
        trySetContentDescription(mHourSpinner, R.id.increment,
                R.string.time_picker_increment_hour_button);
        trySetContentDescription(mHourSpinner, R.id.decrement,
                R.string.time_picker_decrement_hour_button);
        // AM/PM
        if (mAmPmSpinner != null) {
            trySetContentDescription(mAmPmSpinner, R.id.increment,
                    R.string.time_picker_increment_set_pm_button);
            trySetContentDescription(mAmPmSpinner, R.id.decrement,
                    R.string.time_picker_decrement_set_am_button);
        }
    }

    private void trySetContentDescription(View root, int viewId, int contDescResId) {
        View target = root.findViewById(viewId);
        if (target != null) {
            target.setContentDescription(mContext.getString(contDescResId));
        }
    }

    public static String[] getAmPmStrings(Context context) {
        String[] result = new String[2];
        LocaleData d = LocaleData.get(context.getResources().getConfiguration().locale);
        result[0] = d.amPm[0].length() > 4 ? d.narrowAm : d.amPm[0];
        result[1] = d.amPm[1].length() > 4 ? d.narrowPm : d.amPm[1];
        return result;
    }
}