//
//  KMFileAttribute.swift
//  PDF Reader Pro
//
//  Created by tangchao on 2023/10/12.
//

import Cocoa

@objc enum KMNFileAttributePageType: Int {
    case AllPages = 0
    case OnlyOdd
    case OnlyEven
    case PagesString
}

@objcMembers class KMNFileAttribute: NSObject {
    var filePath: String = ""
    var pdfDocument: CPDFDocument?
    var bAllPage = false
    var pagesString: String = ""
    var isLocked = false
    var password: String?
    
    var pagesType: KMNFileAttributePageType = .AllPages
    private var selectPages: [Int] = []
    
    func fetchSelectPages() -> [Int] {
        if let doc = self.pdfDocument, doc.isLocked {
            doc.unlock(withPassword: self.password)
        }
        guard let pdfDocument = pdfDocument else { return [] }
        selectPages.removeAll()

        if pagesType == .AllPages {
            for i in 0..<pdfDocument.pageCount {
                selectPages.append(Int(i) + 1)
            }
            pagesString = "1-\(pdfDocument.pageCount)"
        } else if pagesType == .OnlyOdd {
            pagesString = ""
            for i in 0..<pdfDocument.pageCount where i % 2 == 0 {
                selectPages.append(Int(i) + 1)
                if pagesString == "" {
                    pagesString = "\(i + 1)"
                } else {
                    pagesString = "\(pagesString),\(i + 1)"
                }
            }
        } else if pagesType == .OnlyEven {
            pagesString = ""
            for i in 0..<pdfDocument.pageCount where i % 2 != 0 {
                selectPages.append(Int(i) + 1)
                if pagesString == "" {
                    pagesString = "\(i + 1)"
                } else {
                    pagesString = "\(pagesString),\(i + 1)"
                }
            }
        } else {
            let _ = isInvalidString(pagesString)
            if !bAllPage {
                self.quickSort(&selectPages, startIndex: 0, endIndex: selectPages.count-1)
            }
        }
        
        return selectPages
    }
    
    func isInvalidString(_ text: String) -> Bool {
        var document: CPDFDocument?
        if (pdfDocument != nil) {
            document = pdfDocument
        } else {
            document = CPDFDocument(url:URL(fileURLWithPath: self.filePath ))
        }
        
        if let data = document?.isLocked, data {
            document?.unlock(withPassword: self.password )
        }
        var pageNumber = document?.pageCount ?? 0
        
        if (self.bAllPage) {
            self.selectPages = []
            for i in 1 ... pageNumber {
                self.selectPages.append(Int(i))
            }
            return false
        }
        
        var pageNumbers: [Int] = []
        var isInvalid = false
        for c in text {
            if (c != "0" && c != "1" && c != "2" && c != "3" && c != "4" && c != "5" && c != "6" && c != "7" && c != "8" && c != "9" && c != "," && c != "-") {
                isInvalid = true
                break
            }else{
                isInvalid = false
            }
        }
        if (!isInvalid) {
            let array = text.components(separatedBy: ",")
            for s in array {
                if s.isEmpty {
                    isInvalid = true
                    break
                }else{
                    let pages = s.components(separatedBy: "-")
                    if (pages.count>2) {
                        isInvalid = true
                        break
                    }else if(pages.count==1){
                        let p = pages.first!
                        if p.isEmpty || Int(p)! > pageNumber || Int(p) == 0 {
                            isInvalid = true
                            break
                        }else{
                            var isEqual = false
                            for pageNumber in pageNumbers {
                                if pageNumber == Int(p) {
                                    isEqual = true
                                    isInvalid = true
                                    break
                                }
                            }
                            if (!isEqual) {
                                pageNumbers.append(Int(p)!)
                            }
                        }
                    }else if(pages.count==2){
                        let p1 = pages[0]
                        let p2 = pages[1]
                        if p1.isEmpty || p2.isEmpty || Int(p1)! >= Int(p2)! || Int(p2)! > pageNumber || Int(p1) == 0 {
                            isInvalid = true
                            break
                        }else{
                            var isEqual = false
                            for i in Int(p1)! ... Int(p2)! {
                                for pageNumber in pageNumbers {
                                    if pageNumber == i {
                                        isEqual = true
                                        isInvalid = true
                                        break
                                    }
                                }
                            }
                            if (!isEqual) {
                                for i in Int(p1)! ... Int(p2)! {
                                    pageNumbers.append(i)
                                }
                            }
                        }
                    }
                }
            }
        }
        if (text.isEmpty) {
            isInvalid = true
        }
        if (isInvalid) {
            self.selectPages = []
        }else{
            self.selectPages = pageNumbers
        }
        return isInvalid
    }
    
    func quickSort(_ list: inout [Int],startIndex: Int, endIndex: Int) {
        if(startIndex >= endIndex) {
            return
        }
        
        let temp = list[startIndex]
        var tempIndex = startIndex
        
        for i in startIndex+1 ... endIndex {
            let t = list[i]
            if (temp > t) {
                tempIndex = tempIndex + 1
                
                let tmp = list[tempIndex]
                list[tempIndex] = list[i]
                list[i] = tmp
            }
        }
        
        let tmp = list[tempIndex]
        list[tempIndex] = list[startIndex]
        list[startIndex] = tmp
        
        quickSort(&list, startIndex: startIndex, endIndex: tempIndex-1)
        quickSort(&list, startIndex: tempIndex+1, endIndex: endIndex)
    }
}