import SwiftUI

@main
struct WorkbenchReplacementApp: App {
    @StateObject private var model = DatabaseModel()

    var body: some Scene {
        WindowGroup("Workbench Replacement") {
            MainView()
                .environmentObject(model)
                .frame(minWidth: 1000, minHeight: 650)
        }
        .commands {
            CommandGroup(replacing: .newItem) {}
        }
    

        Settings {
            WorkbenchSettingsView()
        }
}
}


// MARK: - Application Preferences

@MainActor
final class WorkbenchPreferences: ObservableObject {
    static let shared = WorkbenchPreferences()

    @AppStorage("preferences.editorFontSize")
    var editorFontSize = 13.0

    @AppStorage("preferences.uppercaseKeywords")
    var uppercaseKeywords = true

    @AppStorage("preferences.showLineNumbers")
    var showLineNumbers = true

    @AppStorage("preferences.tabWidth")
    var tabWidth = 4

    @AppStorage("preferences.resultRowHeight")
    var resultRowHeight = 24.0

    @AppStorage("preferences.resultColumnWidth")
    var resultColumnWidth = 170.0

    @AppStorage("preferences.alternatingRows")
    var alternatingRows = true

    @AppStorage("preferences.appearance")
    var appearance = "light"

    @AppStorage("preferences.autoExpandTables")
    var autoExpandTables = true
}


// MARK: - Workbench Settings

struct WorkbenchSettingsView: View {

    @AppStorage("preferences.editorFontSize")
    private var editorFontSize = 13.0

    @AppStorage("preferences.uppercaseKeywords")
    private var uppercaseKeywords = true

    @AppStorage("preferences.showLineNumbers")
    private var showLineNumbers = true

    @AppStorage("preferences.tabWidth")
    private var tabWidth = 4

    @AppStorage("preferences.defaultRowLimit")
    private var defaultRowLimit = 500

    @AppStorage("preferences.resultRowHeight")
    private var resultRowHeight = 24.0

    @AppStorage("preferences.resultColumnWidth")
    private var resultColumnWidth = 170.0

    @AppStorage("preferences.alternatingRows")
    private var alternatingRows = true

    @AppStorage("preferences.autoExpandTables")
    private var autoExpandTables = true

    var body: some View {
        TabView {

            editorSettings
                .tabItem {
                    Label(
                        "SQL Editor",
                        systemImage: "chevron.left.forwardslash.chevron.right"
                    )
                }

            executionSettings
                .tabItem {
                    Label(
                        "Query Execution",
                        systemImage: "bolt"
                    )
                }

            resultSettings
                .tabItem {
                    Label(
                        "Result Grid",
                        systemImage: "tablecells"
                    )
                }

            generalSettings
                .tabItem {
                    Label(
                        "General",
                        systemImage: "gearshape"
                    )
                }
        }
        .frame(width: 620, height: 390)
        .preferredColorScheme(.light)
    }

    private var editorSettings: some View {
        settingsPage("SQL Editor") {

            settingsRow("Font Size") {
                Stepper(
                    "\(Int(editorFontSize)) pt",
                    value: $editorFontSize,
                    in: 10...24,
                    step: 1
                )
                .frame(width: 130)
            }

            settingsRow("Tab Width") {
                Picker("", selection: $tabWidth) {
                    Text("2 spaces").tag(2)
                    Text("4 spaces").tag(4)
                    Text("8 spaces").tag(8)
                }
                .labelsHidden()
                .frame(width: 150)
            }

            settingsRow("SQL Formatting") {
                Toggle(
                    "Automatically uppercase SQL keywords",
                    isOn: $uppercaseKeywords
                )
            }

            settingsRow("Editor Display") {
                Toggle(
                    "Show line numbers",
                    isOn: $showLineNumbers
                )
            }
        }
    }

    private var executionSettings: some View {
        settingsPage("Query Execution") {

            settingsRow("Default Row Limit") {
                HStack(spacing: 12) {
                    TextField(
                        "",
                        value: $defaultRowLimit,
                        format: .number
                    )
                    .textFieldStyle(.roundedBorder)
                    .frame(width: 110)

                    Stepper(
                        "",
                        value: $defaultRowLimit,
                        in: 50...100000,
                        step: 50
                    )
                    .labelsHidden()
                }
            }

            Text(
                "Controls the number of rows retrieved when opening a table from the schema navigator."
            )
            .font(.system(size: 12))
            .foregroundStyle(.secondary)
            .frame(maxWidth: .infinity, alignment: .leading)
            .padding(.leading, 190)

            Divider()
                .padding(.vertical, 12)

            Text("Examples")
                .font(.headline)

            Text(
                "500 rows: Faster browsing and lower memory usage.\n" +
                "5,000 rows: Useful for larger datasets.\n" +
                "50,000 rows: May take longer to retrieve."
            )
            .font(.system(size: 12))
            .foregroundStyle(.secondary)
            .frame(maxWidth: .infinity, alignment: .leading)
        }
    }

    private var resultSettings: some View {
        settingsPage("Result Grid") {

            settingsRow("Row Height") {
                Stepper(
                    "\(Int(resultRowHeight)) px",
                    value: $resultRowHeight,
                    in: 18...40,
                    step: 1
                )
                .frame(width: 130)
            }

            settingsRow("Column Width") {
                Stepper(
                    "\(Int(resultColumnWidth)) px",
                    value: $resultColumnWidth,
                    in: 80...400,
                    step: 10
                )
                .frame(width: 140)
            }

            settingsRow("Appearance") {
                Toggle(
                    "Alternating row colours",
                    isOn: $alternatingRows
                )
            }
        }
    }

    private var generalSettings: some View {
        settingsPage("General") {

            settingsRow("Navigator") {
                Toggle(
                    "Automatically expand table folders",
                    isOn: $autoExpandTables
                )
            }
        }
    }

    private func settingsPage<Content: View>(
        _ title: String,
        @ViewBuilder content: () -> Content
    ) -> some View {

        VStack(alignment: .leading, spacing: 18) {

            Text(title)
                .font(.system(size: 20, weight: .semibold))

            Divider()

            content()

            Spacer(minLength: 0)
        }
        .padding(26)
        .frame(maxWidth: .infinity, maxHeight: .infinity)
        .background(Color(nsColor: .windowBackgroundColor))
    }

    private func settingsRow<Content: View>(
        _ title: String,
        @ViewBuilder content: () -> Content
    ) -> some View {

        HStack(alignment: .center, spacing: 16) {

            Text(title)
                .font(.system(size: 13))
                .frame(width: 170, alignment: .trailing)

            content()

            Spacer(minLength: 0)
        }
        .frame(height: 30)
    }
}