// Copyright (c) StellaOps. All rights reserved.
// Licensed under AGPL-3.0-or-later. See LICENSE in the project root.

using System.Collections.Immutable;

namespace StellaOps.BinaryIndex.Ghidra;

/// <summary>
/// Bridge interface for ghidriff Python tool integration.
/// ghidriff provides automated binary diff reports using Ghidra.
/// </summary>
public interface IGhidriffBridge
{
    /// <summary>
    /// Run ghidriff to compare two binaries.
    /// </summary>
    /// <param name="oldBinaryPath">Path to the older binary version.</param>
    /// <param name="newBinaryPath">Path to the newer binary version.</param>
    /// <param name="options">ghidriff configuration options.</param>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>Diff result with added, removed, and modified functions.</returns>
    Task<GhidriffResult> DiffAsync(
        string oldBinaryPath,
        string newBinaryPath,
        GhidriffDiffOptions? options = null,
        CancellationToken ct = default);

    /// <summary>
    /// Run ghidriff to compare two binaries from streams.
    /// </summary>
    /// <param name="oldBinary">Stream of the older binary version.</param>
    /// <param name="newBinary">Stream of the newer binary version.</param>
    /// <param name="options">ghidriff configuration options.</param>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>Diff result with added, removed, and modified functions.</returns>
    Task<GhidriffResult> DiffAsync(
        Stream oldBinary,
        Stream newBinary,
        GhidriffDiffOptions? options = null,
        CancellationToken ct = default);

    /// <summary>
    /// Generate a formatted report from ghidriff results.
    /// </summary>
    /// <param name="result">The diff result to format.</param>
    /// <param name="format">Output format.</param>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>Formatted report string.</returns>
    Task<string> GenerateReportAsync(
        GhidriffResult result,
        GhidriffReportFormat format,
        CancellationToken ct = default);

    /// <summary>
    /// Check if ghidriff is available (Python + ghidriff installed).
    /// </summary>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>True if ghidriff is available.</returns>
    Task<bool> IsAvailableAsync(CancellationToken ct = default);

    /// <summary>
    /// Get ghidriff version information.
    /// </summary>
    /// <param name="ct">Cancellation token.</param>
    /// <returns>Version string.</returns>
    Task<string> GetVersionAsync(CancellationToken ct = default);
}

/// <summary>
/// Options for ghidriff diff operation.
/// </summary>
public sealed record GhidriffDiffOptions
{
    /// <summary>
    /// Path to Ghidra installation (auto-detected if not set).
    /// </summary>
    public string? GhidraPath { get; init; }

    /// <summary>
    /// Path for Ghidra project files (temp dir if not set).
    /// </summary>
    public string? ProjectPath { get; init; }

    /// <summary>
    /// Whether to include decompiled code in results.
    /// </summary>
    public bool IncludeDecompilation { get; init; } = true;

    /// <summary>
    /// Whether to include disassembly listing in results.
    /// </summary>
    public bool IncludeDisassembly { get; init; } = true;

    /// <summary>
    /// Functions to exclude from comparison (by name pattern).
    /// </summary>
    public ImmutableArray<string> ExcludeFunctions { get; init; } = [];

    /// <summary>
    /// Maximum number of concurrent Ghidra instances.
    /// </summary>
    public int MaxParallelism { get; init; } = 1;

    /// <summary>
    /// Maximum analysis time in seconds.
    /// </summary>
    public int TimeoutSeconds { get; init; } = 600;
}

/// <summary>
/// Result of a ghidriff comparison.
/// </summary>
/// <param name="OldBinaryHash">SHA256 hash of the old binary.</param>
/// <param name="NewBinaryHash">SHA256 hash of the new binary.</param>
/// <param name="OldBinaryName">Name/path of the old binary.</param>
/// <param name="NewBinaryName">Name/path of the new binary.</param>
/// <param name="AddedFunctions">Functions added in new binary.</param>
/// <param name="RemovedFunctions">Functions removed from old binary.</param>
/// <param name="ModifiedFunctions">Functions modified between versions.</param>
/// <param name="Statistics">Comparison statistics.</param>
/// <param name="RawJsonOutput">Raw JSON output from ghidriff.</param>
public sealed record GhidriffResult(
    string OldBinaryHash,
    string NewBinaryHash,
    string OldBinaryName,
    string NewBinaryName,
    ImmutableArray<GhidriffFunction> AddedFunctions,
    ImmutableArray<GhidriffFunction> RemovedFunctions,
    ImmutableArray<GhidriffDiff> ModifiedFunctions,
    GhidriffStats Statistics,
    string RawJsonOutput);

/// <summary>
/// A function from ghidriff output.
/// </summary>
/// <param name="Name">Function name.</param>
/// <param name="Address">Function address.</param>
/// <param name="Size">Function size in bytes.</param>
/// <param name="Signature">Decompiled signature.</param>
/// <param name="DecompiledCode">Decompiled C code (if requested).</param>
public sealed record GhidriffFunction(
    string Name,
    ulong Address,
    int Size,
    string? Signature,
    string? DecompiledCode);

/// <summary>
/// A function diff from ghidriff output.
/// </summary>
/// <param name="FunctionName">Function name.</param>
/// <param name="OldAddress">Address in old binary.</param>
/// <param name="NewAddress">Address in new binary.</param>
/// <param name="OldSize">Size in old binary.</param>
/// <param name="NewSize">Size in new binary.</param>
/// <param name="OldSignature">Signature in old binary.</param>
/// <param name="NewSignature">Signature in new binary.</param>
/// <param name="Similarity">Similarity score.</param>
/// <param name="OldDecompiled">Decompiled code from old binary.</param>
/// <param name="NewDecompiled">Decompiled code from new binary.</param>
/// <param name="InstructionChanges">List of instruction-level changes.</param>
public sealed record GhidriffDiff(
    string FunctionName,
    ulong OldAddress,
    ulong NewAddress,
    int OldSize,
    int NewSize,
    string? OldSignature,
    string? NewSignature,
    decimal Similarity,
    string? OldDecompiled,
    string? NewDecompiled,
    ImmutableArray<string> InstructionChanges);

/// <summary>
/// Statistics from ghidriff comparison.
/// </summary>
/// <param name="TotalOldFunctions">Total functions in old binary.</param>
/// <param name="TotalNewFunctions">Total functions in new binary.</param>
/// <param name="AddedCount">Number of added functions.</param>
/// <param name="RemovedCount">Number of removed functions.</param>
/// <param name="ModifiedCount">Number of modified functions.</param>
/// <param name="UnchangedCount">Number of unchanged functions.</param>
/// <param name="AnalysisDuration">Time taken for analysis.</param>
public sealed record GhidriffStats(
    int TotalOldFunctions,
    int TotalNewFunctions,
    int AddedCount,
    int RemovedCount,
    int ModifiedCount,
    int UnchangedCount,
    TimeSpan AnalysisDuration);

/// <summary>
/// Report output format for ghidriff.
/// </summary>
public enum GhidriffReportFormat
{
    /// <summary>JSON format.</summary>
    Json,

    /// <summary>Markdown format.</summary>
    Markdown,

    /// <summary>HTML format.</summary>
    Html
}