//
//  FormatterView.swift
//  Note
//
//  Created by fish on 2026/7/12.
//

import SwiftUI

struct FormatterView: View {
    @State private var inputText: String = ""
    @State private var showEmptyAlert: Bool = false
    @State private var showCopied: Bool = false

    var body: some View {
        NavigationStack {
            VStack(spacing: 0) {
                headerView

                inputArea
                    .frame(maxHeight: .infinity)

                actionArea
            }
            .background(Color(.systemGroupedBackground).ignoresSafeArea())
            .alert("提示", isPresented: $showEmptyAlert) {
                Button("确定", role: .cancel) {}
            } message: {
                Text("请输入需要格式化的文案")
            }
            .overlay {
                if showCopied {
                    VStack {
                        Spacer()
                        Text("已复制")
                            .font(.subheadline)
                            .padding(.horizontal, 16)
                            .padding(.vertical, 8)
                            .background(Color.black.opacity(0.75))
                            .foregroundStyle(.white)
                            .cornerRadius(20)
                            .padding(.bottom, 32)
                    }
                    .transition(.opacity)
                }
            }
            .navigationBarHidden(true)
        }
    }

    private var headerView: some View {
        HStack {
            Text("文案格式化")
                .font(.largeTitle.bold())
                .foregroundStyle(.primary)
            Spacer()
            if !inputText.isEmpty {
                Button(action: copyText) {
                    Image(systemName: "doc.on.doc")
                }
                .font(.title3)
            }
        }
        .frame(maxWidth: .infinity, minHeight: 44)
        .padding(.horizontal)
        .padding(.top, 8)
        .padding(.bottom, 8)
        .background(Color(.systemGroupedBackground))
        .contentShape(Rectangle())
        .onTapGesture {
            dismissKeyboard()
        }
    }

    private var inputArea: some View {
        VStack(alignment: .leading, spacing: 8) {
            Text("输入")
                .font(.subheadline)
                .foregroundStyle(.secondary)
                .padding(.horizontal)

            TextEditor(text: $inputText)
                .frame(maxWidth: .infinity, maxHeight: .infinity)
                .padding(12)
                .background(Color(.systemBackground))
                .cornerRadius(12)
                .overlay(
                    RoundedRectangle(cornerRadius: 12)
                        .stroke(Color(.systemGray4), lineWidth: 1)
                )
                .padding(.horizontal)
                .toolbar {
                    ToolbarItemGroup(placement: .keyboard) {
                        Spacer()
                        Button("完成") {
                            dismissKeyboard()
                        }
                    }
                }

            Text("粘贴需要格式化的文案")
                .font(.subheadline)
                .foregroundStyle(.secondary)
                .padding(.horizontal)
        }
        .padding(.vertical, 8)
    }

    private var actionArea: some View {
        Button(action: formatText) {
            Label("格式化", systemImage: "wand.and.stars")
                .font(.headline)
                .frame(maxWidth: .infinity)
                .padding()
                .background(Color(.systemBackground))
                .foregroundStyle(Color.accentColor)
                .cornerRadius(12)
        }
        .padding()
        .background(Color(.systemGroupedBackground))
    }

    private func dismissKeyboard() {
        UIApplication.shared.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
    }

    private func formatText() {
        if inputText.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty {
            showEmptyAlert = true
            return
        }

        var content = inputText

        // 去 #
        content = content.replacingOccurrences(of: "# ", with: "")
        content = content.replacingOccurrences(of: "#", with: "")
        // 将 ; 转为句号
        content = content.replacingOccurrences(of: ";", with: "。")
        // 将 ； 转为句号
        content = content.replacingOccurrences(of: "；", with: "。")
        // 将 . 转为句号
        content = content.replacingOccurrences(of: ".", with: "。")
        // 将 （ 转为 (
        content = content.replacingOccurrences(of: "（", with: "(")
        // 将 ） 转为 )
        content = content.replacingOccurrences(of: "）", with: ")")
        // 将 ? 转为 ？
        content = content.replacingOccurrences(of: "?", with: "？")
        // 将 , 转为 ，
        content = content.replacingOccurrences(of: ",", with: "，")
        // 将 : 转为 ：
        content = content.replacingOccurrences(of: ":", with: "：")
        // 将 日星期 转为 日 星期
        content = content.replacingOccurrences(of: "日星期", with: "日 星期")
        // 在第一行插入 #
        content = "# " + content
        // 标题设置
        content = content.replacingOccurrences(of: "一、生活方面", with: "## 一、生活方面")
        content = content.replacingOccurrences(of: "二、交易方面", with: "## 二、交易方面")
        content = content.replacingOccurrences(of: "三、工作方面", with: "## 三、工作方面")

        inputText = content
        dismissKeyboard()
    }

    private func copyText() {
        UIPasteboard.general.string = inputText
        withAnimation {
            showCopied = true
        }
        DispatchQueue.main.asyncAfter(deadline: .now() + 1.5) {
            withAnimation {
                showCopied = false
            }
        }
    }
}

#Preview {
    FormatterView()
}