import MusicAssistantCore
import SwiftUI

struct MusicalParametersEditorView: View {
    @Binding var project: SongProject

    var body: some View {
        VStack(alignment: .leading, spacing: 12) {
            ManualAutoIntegerRow(
                title: "BPM",
                value: manualAutoIntegerBinding(\.bpm)
            )
            ManualAutoTextRow(
                title: "Key",
                value: manualAutoTextBinding(\.key),
                placeholder: "D"
            )
            ManualAutoTextRow(
                title: "Scale",
                value: manualAutoTextBinding(\.scale),
                placeholder: "minor"
            )
            ManualAutoTextRow(
                title: "Maqam",
                value: manualAutoTextBinding(\.maqam),
                placeholder: "Hijaz"
            )
        }
    }

    private func manualAutoIntegerBinding(
        _ keyPath: WritableKeyPath<SongProject, ManualAutoValue<Int>?>
    ) -> Binding<ManualAutoValue<Int>> {
        Binding {
            project[keyPath: keyPath] ?? ManualAutoValue(mode: .auto)
        } set: { newValue in
            project[keyPath: keyPath] = newValue
        }
    }

    private func manualAutoTextBinding(
        _ keyPath: WritableKeyPath<SongProject, ManualAutoValue<String>?>
    ) -> Binding<ManualAutoValue<String>> {
        Binding {
            project[keyPath: keyPath] ?? ManualAutoValue(mode: .auto)
        } set: { newValue in
            project[keyPath: keyPath] = newValue
        }
    }
}

private struct ManualAutoIntegerRow: View {
    let title: String
    @Binding var value: ManualAutoValue<Int>

    var body: some View {
        VStack(alignment: .leading, spacing: 8) {
            ManualAutoPicker(title: title, mode: modeBinding)

            if value.mode == .manual {
                TextField(title, text: integerTextBinding)
            }
        }
    }

    private var modeBinding: Binding<ControlMode> {
        Binding {
            value.mode
        } set: { newMode in
            value = ManualAutoValue(
                mode: newMode,
                value: newMode == .manual ? value.value : nil
            )
        }
    }

    private var integerTextBinding: Binding<String> {
        Binding {
            value.value.map(String.init) ?? ""
        } set: { newValue in
            value.value = Int(newValue.trimmingCharacters(in: .whitespacesAndNewlines))
        }
    }
}

private struct ManualAutoTextRow: View {
    let title: String
    @Binding var value: ManualAutoValue<String>
    let placeholder: String

    var body: some View {
        VStack(alignment: .leading, spacing: 8) {
            ManualAutoPicker(title: title, mode: modeBinding)

            if value.mode == .manual {
                TextField(placeholder, text: textBinding)
            }
        }
    }

    private var modeBinding: Binding<ControlMode> {
        Binding {
            value.mode
        } set: { newMode in
            value = ManualAutoValue(
                mode: newMode,
                value: newMode == .manual ? value.value : nil
            )
        }
    }

    private var textBinding: Binding<String> {
        Binding {
            value.value ?? ""
        } set: { newValue in
            let trimmedValue = newValue.trimmingCharacters(in: .whitespacesAndNewlines)
            value.value = trimmedValue.isEmpty ? nil : trimmedValue
        }
    }
}

private struct ManualAutoPicker: View {
    let title: String
    @Binding var mode: ControlMode

    var body: some View {
        Picker(title, selection: $mode) {
            Text("Auto").tag(ControlMode.auto)
            Text("Manual").tag(ControlMode.manual)
        }
        .pickerStyle(.segmented)
    }
}

#Preview {
    MusicalParametersEditorPreview()
}

private struct MusicalParametersEditorPreview: View {
    @State private var project = SongProject(
        title: "Parameters",
        idea: "Preview",
        bpm: ManualAutoValue(mode: .manual, value: 96),
        key: ManualAutoValue(mode: .auto),
        scale: ManualAutoValue(mode: .manual, value: "minor"),
        maqam: ManualAutoValue(mode: .auto)
    )

    var body: some View {
        Form {
            MusicalParametersEditorView(project: $project)
        }
        .formStyle(.grouped)
        .frame(width: 340)
    }
}