import SwiftUI
import UIKit

struct EnhancedConsoleView: View {
    let lines: [ConsoleLine]
    var onClear: (() -> Void)? = nil

    @State private var filterMode: FilterMode = .all
    @State private var searchText   = ""
    @State private var showSearch   = false
    @State private var isPinned     = true
    @State private var fontSize: CGFloat = 11

    enum FilterMode: String, CaseIterable {
        case all, errors, warnings, info
        var label: String { rawValue.capitalized }
        var icon: String {
            switch self {
            case .all: return "list.bullet"; case .errors: return "xmark.circle"
            case .warnings: return "exclamationmark.triangle"; case .info: return "info.circle"
            }
        }
    }

    private var filtered: [ConsoleLine] {
        var result = lines
        switch filterMode {
        case .errors:   result = result.filter { $0.type == .error   }
        case .warnings: result = result.filter { $0.type == .warning }
        case .info:     result = result.filter { $0.type == .info || $0.type == .standard }
        case .all: break
        }
        if !searchText.isEmpty {
            result = result.filter { $0.text.localizedCaseInsensitiveContains(searchText) }
        }
        return result
    }

    private var errorCount:   Int { lines.filter { $0.type == .error   }.count }
    private var warningCount: Int { lines.filter { $0.type == .warning }.count }

    var body: some View {
        VStack(spacing: 0) {
            // Toolbar
            HStack(spacing: 6) {
                ForEach(FilterMode.allCases, id: \.self) { mode in
                    Button {
                        filterMode = mode
                    } label: {
                        HStack(spacing: 3) {
                            Image(systemName: mode.icon).font(.system(size: 10))
                            if mode == .errors && errorCount > 0   { Text("\(errorCount)").font(.system(.caption2, design: .monospaced).bold()) }
                            if mode == .warnings && warningCount > 0 { Text("\(warningCount)").font(.system(.caption2, design: .monospaced).bold()) }
                        }
                        .padding(.horizontal, 7).padding(.vertical, 3)
                        .background(filterMode == mode ? pillColor(mode).opacity(0.2) : Color(.tertiarySystemFill),
                                    in: RoundedRectangle(cornerRadius: 5))
                        .foregroundStyle(filterMode == mode ? pillColor(mode) : .secondary)
                    }
                    .buttonStyle(.plain)
                }
                Spacer()
                Button { withAnimation { showSearch.toggle(); if !showSearch { searchText = "" } } }
                label: { Image(systemName: "magnifyingglass").foregroundStyle(showSearch ? Color.accentColor : Color.secondary) }
                .buttonStyle(.plain)
                Button { UIPasteboard.general.string = filtered.map(\.text).joined(separator: "\n") }
                label: { Image(systemName: "doc.on.doc").foregroundStyle(.secondary) }.buttonStyle(.plain)
                Button { isPinned.toggle() }
                label: { Image(systemName: isPinned ? "pin.fill" : "pin.slash").foregroundStyle(isPinned ? Color.accentColor : Color.secondary) }
                .buttonStyle(.plain)
                if let clear = onClear {
                    Button(action: clear) { Image(systemName: "trash").foregroundStyle(.secondary) }.buttonStyle(.plain)
                }
            }
            .padding(.horizontal, 10).padding(.vertical, 5)
            .background(Color(.secondarySystemBackground))

            if showSearch {
                HStack(spacing: 6) {
                    Image(systemName: "magnifyingglass").foregroundStyle(.secondary).font(.caption)
                    TextField("Filter output…", text: $searchText)
                        .font(.system(.callout, design: .monospaced)).autocorrectionDisabled().autocapitalization(.none)
                    if !searchText.isEmpty {
                        Button { searchText = "" } label: { Image(systemName: "xmark.circle.fill").foregroundStyle(.secondary) }.buttonStyle(.plain)
                        Text("\(filtered.count)").font(.caption2).foregroundStyle(.secondary)
                    }
                }
                .padding(.horizontal, 10).padding(.vertical, 6).background(Color(.systemBackground))
                Divider()
            }

            Divider()

            ScrollViewReader { proxy in
                ScrollView {
                    LazyVStack(alignment: .leading, spacing: 0) {
                        ForEach(filtered) { line in
                            HStack(alignment: .top, spacing: 4) {
                                Rectangle().fill(gutterColor(line.type)).frame(width: 2).padding(.vertical, 1)
                                Text(line.text)
                                    .font(.system(size: fontSize, design: .monospaced))
                                    .foregroundStyle(line.color)
                                    .textSelection(.enabled)
                                    .frame(maxWidth: .infinity, alignment: .leading)
                            }
                            .padding(.vertical, 1)
                            .id(line.id)
                        }
                    }
                    .padding(.horizontal, 8).padding(.vertical, 4)
                }
                .background(Color(.systemBackground))
                .onChange(of: filtered.count) { _, _ in
                    if isPinned, let last = filtered.last {
                        withAnimation(.linear(duration: 0.08)) { proxy.scrollTo(last.id, anchor: .bottom) }
                    }
                }
            }
        }
    }

    private func pillColor(_ mode: FilterMode) -> Color {
        switch mode {
        case .errors: return .red; case .warnings: return .orange
        case .info: return .blue; case .all: return Color.accentColor
        }
    }
    private func gutterColor(_ type: ConsoleLine.LineType) -> Color {
        switch type {
        case .error: return .red; case .warning: return .orange
        case .success: return .green; case .info: return Color.accentColor; default: return .clear
        }
    }
}