/*
 * Copyright [2019] [Doric.Pub]
 *
 * 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.
 */
//
// Created by pengfei.zhou on 2019/11/15.
//

#import <JavaScriptCore/JavaScriptCore.h>
#import "DoricListNode.h"
#import "DoricExtensions.h"
#import "DoricListItemNode.h"

@interface DoricTableViewCell : UITableViewCell
@property(nonatomic, strong) DoricListItemNode *doricListItemNode;
@end

@implementation DoricTableViewCell
@end

@interface DoricTableView : UITableView
@end

@implementation DoricTableView
- (CGSize)sizeThatFits:(CGSize)size {
    if (self.subviews.count > 0) {
        CGFloat width = size.width;
        CGFloat height = 0;

        for (UIView *child in self.subviews) {
            width = MAX(child.width, width);
            height += child.height;
        }
        return CGSizeMake(width, height);
    }
    return size;
}
@end


@interface DoricListNode () <UITableViewDataSource, UITableViewDelegate>
@property(nonatomic, strong) NSMutableDictionary <NSNumber *, NSString *> *itemViewIds;
@property(nonatomic, strong) NSMutableDictionary <NSNumber *, NSNumber *> *itemHeights;
@property(nonatomic, assign) NSUInteger itemCount;
@property(nonatomic, assign) NSUInteger batchCount;
@end

@implementation DoricListNode
- (instancetype)initWithContext:(DoricContext *)doricContext {
    if (self = [super initWithContext:doricContext]) {
        _itemViewIds = [NSMutableDictionary new];
        _itemHeights = [NSMutableDictionary new];
        _batchCount = 15;
    }
    return self;
}

- (UITableView *)build {
    return [[DoricTableView new] also:^(UITableView *it) {
        it.dataSource = self;
        it.delegate = self;
        it.separatorStyle = UITableViewCellSeparatorStyleNone;
    }];
}

- (void)blendView:(UITableView *)view forPropName:(NSString *)name propValue:(id)prop {
    if ([@"itemCount" isEqualToString:name]) {
        self.itemCount = [prop unsignedIntegerValue];
        [self.view reloadData];
    } else if ([@"renderItem" isEqualToString:name]) {
        [self.itemViewIds removeAllObjects];
        [self clearSubModel];
        [self.view reloadData];
    } else if ([@"batchCount" isEqualToString:name]) {
        self.batchCount = [prop unsignedIntegerValue];
    } else {
        [super blendView:view forPropName:name propValue:prop];
    }
}

- (void)blend:(NSDictionary *)props {
    [super blend:props];
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    return self.itemCount;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    NSUInteger position = (NSUInteger) indexPath.row;
    NSDictionary *model = [self itemModelAt:position];
    NSDictionary *props = model[@"props"];
    NSString *reuseId = props[@"identifier"];

    DoricTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:reuseId ?: @"doriccell"];
    if (!cell) {
        cell = [[DoricTableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:reuseId ?: @"doriccell"];
        DoricListItemNode *listItemNode = [[DoricListItemNode alloc] initWithContext:self.doricContext];
        [listItemNode initWithSuperNode:self];
        cell.doricListItemNode = listItemNode;
        [cell.contentView addSubview:listItemNode.view];
    }
    DoricListItemNode *node = cell.doricListItemNode;
    node.viewId = model[@"id"];
    [node blend:props];
    [node.view setNeedsLayout];
    CGSize size = [node.view sizeThatFits:CGSizeMake(cell.width, cell.height)];
    [self callItem:position height:size.height];
    return cell;
}

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
    NSUInteger position = (NSUInteger) indexPath.row;
    NSNumber *heightNumber = self.itemHeights[@(position)];
    if (heightNumber) {
        return [heightNumber floatValue];
    } else {
        return 44.f;
    }

}

- (NSDictionary *)itemModelAt:(NSUInteger)position {
    NSString *viewId = self.itemViewIds[@(position)];
    if (viewId && viewId.length > 0) {
        return [self subModelOf:viewId];
    } else {
        DoricAsyncResult *result = [self callJSResponse:@"renderBunchedItems", @(position), @(self.batchCount), nil];
        JSValue *models = [result waitUntilResult];
        NSArray *array = [models toArray];
        [array enumerateObjectsUsingBlock:^(NSDictionary *obj, NSUInteger idx, BOOL *stop) {
            NSString *thisViewId = obj[@"id"];
            [self setSubModel:obj in:thisViewId];
            NSUInteger pos = position + idx;
            self.itemViewIds[@(pos)] = thisViewId;
        }];
        return array[0];
    }
}

- (void)blendSubNode:(NSDictionary *)subModel {
    NSString *viewId = subModel[@"id"];
    DoricViewNode *viewNode = [self subNodeWithViewId:viewId];
    if (viewNode) {
        [viewNode blend:subModel[@"props"]];
    } else {
        NSMutableDictionary *model = [[self subModelOf:viewId] mutableCopy];
        [self recursiveMixin:subModel to:model];
        [self setSubModel:model in:viewId];
    }
    [self.itemViewIds enumerateKeysAndObjectsUsingBlock:^(NSNumber *_Nonnull key, NSString *_Nonnull obj, BOOL *_Nonnull stop) {
        if ([viewId isEqualToString:obj]) {
            *stop = YES;
            NSIndexPath *indexPath = [NSIndexPath indexPathForRow:[key integerValue] inSection:0];
            [UIView performWithoutAnimation:^{
                [self.view reloadRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationNone];
            }];
        }
    }];
}

- (void)callItem:(NSUInteger)position height:(CGFloat)height {
    NSNumber *old = self.itemHeights[@(position)];
    if (old && old.floatValue == height) {
        return;
    }
    self.itemHeights[@(position)] = @(height);
    NSIndexPath *indexPath = [NSIndexPath indexPathForRow:position inSection:0];
    [UIView performWithoutAnimation:^{
        [self.view reloadRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationNone];
    }];
}

- (DoricViewNode *)subNodeWithViewId:(NSString *)viewId {
    __block DoricViewNode *ret = nil;
    [self.doricContext.driver ensureSyncInMainQueue:^{
        for (UITableViewCell *tableViewCell in self.view.visibleCells) {
            if ([tableViewCell isKindOfClass:[DoricTableViewCell class]]) {
                DoricListItemNode *node = ((DoricTableViewCell *) tableViewCell).doricListItemNode;
                if ([viewId isEqualToString:node.viewId]) {
                    ret = node;
                    break;
                }
            }
        }
    }];
    return ret;
}

@end