// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

using System.Threading;
using System.Threading.Tasks;
using Microsoft.CodeAnalysis.Indentation;
using Microsoft.CodeAnalysis.Shared.Extensions;

namespace Microsoft.CodeAnalysis.Wrapping.SeparatedSyntaxList;

/// <summary>
/// Base type for all wrappers that involve wrapping a comma-separated list of items.
/// </summary>
internal abstract partial class AbstractSeparatedSyntaxListWrapper<
    TListSyntax,
    TListItemSyntax>
    : AbstractSyntaxWrapper
    where TListSyntax : SyntaxNode
    where TListItemSyntax : SyntaxNode
{
    protected abstract string Unwrap_list { get; }
    protected abstract string Wrap_long_list { get; }

    protected abstract string Unwrap_and_indent_all_items { get; }
    protected abstract string Unwrap_all_items { get; }
    protected abstract string Indent_all_items { get; }
    protected abstract string Align_wrapped_items { get; }
    protected abstract string Indent_wrapped_items { get; }

    protected abstract string Wrap_every_item { get; }

    public abstract bool Supports_WrapEveryGroup_UnwrapFirst { get; }
    public abstract bool Supports_UnwrapGroup_WrapFirst_IndentRest { get; }
    public abstract bool Supports_WrapLongGroup_UnwrapFirst { get; }

    protected AbstractSeparatedSyntaxListWrapper(IIndentationService indentationService)
        : base(indentationService)
    {
    }

    protected abstract bool ShouldMoveCloseBraceToNewLine { get; }
    protected abstract bool ShouldMoveOpenBraceToNewLine(SyntaxWrappingOptions options);

    protected abstract SyntaxToken FirstToken(TListSyntax listSyntax);
    protected abstract SyntaxToken LastToken(TListSyntax listSyntax);
    protected abstract TListSyntax? TryGetApplicableList(SyntaxNode node);
    protected abstract SeparatedSyntaxList<TListItemSyntax> GetListItems(TListSyntax listSyntax);
    protected abstract bool PositionIsApplicable(
        SyntaxNode root, int position, SyntaxNode declaration, bool containsSyntaxError, TListSyntax listSyntax);

    public override async Task<ICodeActionComputer?> TryCreateComputerAsync(
        Document document, int position, SyntaxNode declaration, SyntaxWrappingOptions options, bool containsSyntaxError, CancellationToken cancellationToken)
    {
        var listSyntax = TryGetApplicableList(declaration);
        if (listSyntax == null || listSyntax.Span.IsEmpty)
            return null;

        var firstToken = FirstToken(listSyntax);
        var lastToken = LastToken(listSyntax);

        if (firstToken.IsMissing || lastToken.IsMissing || firstToken.Span.IsEmpty || lastToken.Span.IsEmpty)
            return null;

        var root = await document.GetRequiredSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
        if (!PositionIsApplicable(root, position, declaration, containsSyntaxError, listSyntax))
            return null;

        var listItems = GetListItems(listSyntax);
        if (listItems.Count <= 1)
        {
            // nothing to do with 0-1 items.  Simple enough for users to just edit
            // themselves, and this prevents constant clutter with formatting that isn't
            // really that useful.
            return null;
        }

        var containsUnformattableContent = await ContainsUnformattableContentAsync(
            document, listItems.GetWithSeparators(), cancellationToken).ConfigureAwait(false);

        if (containsUnformattableContent)
            return null;

        var sourceText = await document.GetValueTextAsync(cancellationToken).ConfigureAwait(false);
        return new SeparatedSyntaxListCodeActionComputer(
            this, document, sourceText, options, listSyntax, listItems);
    }
}