/*
 * Copyright (c) 2024-2025 Sun Booshi
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

import { App, TFile, MetadataCache } from 'obsidian';

export interface FilterCondition {
    type: 'tag' | 'filename' | 'folder' | 'frontmatter';
    operator: 'contains' | 'equals' | 'startsWith' | 'endsWith' | 'exists';
    value?: string;
    key?: string; // for frontmatter
}

export interface BatchFilterConfig {
    conditions: FilterCondition[];
    logic: 'and' | 'or';
    orderBy?: 'name' | 'created' | 'modified';
    orderDirection?: 'asc' | 'desc';
}

export class BatchArticleFilter {
    private app: App;
    private metadataCache: MetadataCache;

    constructor(app: App) {
        this.app = app;
        this.metadataCache = app.metadataCache;
    }

    /**
     * 筛选文章
     */
    async filterArticles(config: BatchFilterConfig): Promise<TFile[]> {
        const allMarkdownFiles = this.app.vault.getMarkdownFiles();
        const filtered = allMarkdownFiles.filter(file => this.matchesConditions(file, config));
        
        return this.sortFiles(filtered, config.orderBy || 'name', config.orderDirection || 'asc');
    }

    /**
     * 检查文件是否匹配条件
     */
    private matchesConditions(file: TFile, config: BatchFilterConfig): boolean {
        const { conditions, logic } = config;
        
        if (conditions.length === 0) return true;
        
        const results = conditions.map(condition => this.checkCondition(file, condition));
        
        if (logic === 'and') {
            return results.every(result => result);
        } else {
            return results.some(result => result);
        }
    }

    /**
     * 检查单个条件
     */
    private checkCondition(file: TFile, condition: FilterCondition): boolean {
        const { type, operator, value, key } = condition;
        
        switch (type) {
            case 'tag':
                return this.checkTagCondition(file, operator, value);
            case 'filename':
                return this.checkFilenameCondition(file, operator, value);
            case 'folder':
                return this.checkFolderCondition(file, operator, value);
            case 'frontmatter':
                return this.checkFrontmatterCondition(file, operator, key, value);
            default:
                return false;
        }
    }

    /**
     * 检查标签条件
     */
    private checkTagCondition(file: TFile, operator: string, value?: string): boolean {
        if (!value) return false;
        
        const fileCache = this.metadataCache.getFileCache(file);
        const tags = fileCache?.tags?.map(t => t.tag.replace('#', '')) || [];
        const frontmatterTags = fileCache?.frontmatter?.tags || [];
        const allTags = [...tags, ...frontmatterTags].map(tag => 
            typeof tag === 'string' ? tag : String(tag)
        );
        
        switch (operator) {
            case 'contains':
                return allTags.some(tag => tag.includes(value));
            case 'equals':
                return allTags.includes(value);
            case 'exists':
                return allTags.length > 0;
            default:
                return false;
        }
    }

    /**
     * 检查文件名条件
     */
    private checkFilenameCondition(file: TFile, operator: string, value?: string): boolean {
        if (!value) return false;
        
        const filename = file.basename;
        
        switch (operator) {
            case 'contains':
                return filename.includes(value);
            case 'equals':
                return filename === value;
            case 'startsWith':
                return filename.startsWith(value);
            case 'endsWith':
                return filename.endsWith(value);
            default:
                return false;
        }
    }

    /**
     * 检查文件夹条件
     */
    private checkFolderCondition(file: TFile, operator: string, value?: string): boolean {
        if (!value) return false;
        
        const folderPath = file.parent?.path || '';
        
        switch (operator) {
            case 'contains':
                return folderPath.includes(value);
            case 'equals':
                return folderPath === value;
            case 'startsWith':
                return folderPath.startsWith(value);
            default:
                return false;
        }
    }

    /**
     * 检查 frontmatter 条件
     */
    private checkFrontmatterCondition(file: TFile, operator: string, key?: string, value?: string): boolean {
        if (!key) return false;
        
        const fileCache = this.metadataCache.getFileCache(file);
        const frontmatter = fileCache?.frontmatter;
        
        if (!frontmatter) return false;
        
        const fieldValue = frontmatter[key];
        
        switch (operator) {
            case 'exists':
                return fieldValue !== undefined;
            case 'equals':
                return String(fieldValue) === value;
            case 'contains':
                return value ? String(fieldValue).includes(value) : false;
            default:
                return false;
        }
    }

    /**
     * 排序文件
     */
    private sortFiles(files: TFile[], orderBy: string, direction: string): TFile[] {
        return files.sort((a, b) => {
            let compareResult = 0;
            
            switch (orderBy) {
                case 'name':
                    compareResult = a.basename.localeCompare(b.basename);
                    break;
                case 'created':
                    compareResult = a.stat.ctime - b.stat.ctime;
                    break;
                case 'modified':
                    compareResult = a.stat.mtime - b.stat.mtime;
                    break;
                default:
                    compareResult = a.basename.localeCompare(b.basename);
            }
            
            return direction === 'desc' ? -compareResult : compareResult;
        });
    }

    /**
     * 从类似 database view 的配置创建筛选条件
     */
    static fromDatabaseConfig(config: any): BatchFilterConfig {
        const conditions: FilterCondition[] = [];
        
        if (config.filters?.and) {
            for (const filter of config.filters.and) {
                if (filter['file.tags.contains']) {
                    conditions.push({
                        type: 'tag',
                        operator: 'contains',
                        value: filter['file.tags.contains']
                    });
                }
                // 可以扩展更多条件类型
            }
        }
        
        let orderBy: 'name' | 'created' | 'modified' = 'name';
        if (config.order?.[0] === 'file.name') {
            orderBy = 'name';
        } else if (config.order?.[0] === 'file.ctime') {
            orderBy = 'created';
        } else if (config.order?.[0] === 'file.mtime') {
            orderBy = 'modified';
        }
        
        return {
            conditions,
            logic: 'and',
            orderBy,
            orderDirection: 'asc'
        };
    }
}