using System.Collections.Immutable;

namespace StellaOps.Policy.Licensing;

public interface ILicenseComplianceEvaluator
{
    Task<LicenseComplianceReport> EvaluateAsync(
        IReadOnlyList<LicenseComponent> components,
        LicensePolicy policy,
        CancellationToken ct = default);
}

public sealed record LicenseComponent
{
    public required string Name { get; init; }
    public string? Version { get; init; }
    public string? Purl { get; init; }
    public string? LicenseExpression { get; init; }
    public ImmutableArray<string> Licenses { get; init; } = [];
    public ImmutableDictionary<string, string> Metadata { get; init; } = ImmutableDictionary<string, string>.Empty;
}

public sealed record LicenseComplianceReport
{
    public LicenseInventory Inventory { get; init; } = new();
    public ImmutableArray<LicenseFinding> Findings { get; init; } = [];
    public ImmutableArray<LicenseConflict> Conflicts { get; init; } = [];
    public LicenseComplianceStatus OverallStatus { get; init; } = LicenseComplianceStatus.Pass;
    public ImmutableArray<AttributionRequirement> AttributionRequirements { get; init; } = [];
}

public sealed record LicenseInventory
{
    public ImmutableArray<LicenseUsage> Licenses { get; init; } = [];
    public ImmutableDictionary<LicenseCategory, int> ByCategory { get; init; } =
        ImmutableDictionary<LicenseCategory, int>.Empty;
    public int UnknownLicenseCount { get; init; }
    public int NoLicenseCount { get; init; }
}

public sealed record LicenseUsage
{
    public required string LicenseId { get; init; }
    public string? Expression { get; init; }
    public LicenseCategory Category { get; init; }
    public ImmutableArray<string> Components { get; init; } = [];
    public int Count { get; init; }
}

public sealed record LicenseFinding
{
    public required LicenseFindingType Type { get; init; }
    public required string LicenseId { get; init; }
    public required string ComponentName { get; init; }
    public string? ComponentPurl { get; init; }
    public LicenseCategory Category { get; init; }
    public string? Message { get; init; }
}

public sealed record LicenseConflict
{
    public required string ComponentName { get; init; }
    public string? ComponentPurl { get; init; }
    public ImmutableArray<string> LicenseIds { get; init; } = [];
    public string? Reason { get; init; }
}

public sealed record AttributionRequirement
{
    public required string ComponentName { get; init; }
    public string? ComponentPurl { get; init; }
    public required string LicenseId { get; init; }
    public ImmutableArray<string> Notices { get; init; } = [];
    public bool IncludeLicenseText { get; init; }
}

public sealed record LicenseObligation
{
    public required LicenseObligationType Type { get; init; }
    public string? Details { get; init; }
}

public enum LicenseComplianceStatus
{
    Pass = 0,
    Warn = 1,
    Fail = 2
}

public enum LicenseFindingType
{
    ProhibitedLicense = 0,
    CopyleftInProprietaryContext = 1,
    LicenseConflict = 2,
    UnknownLicense = 3,
    MissingLicense = 4,
    AttributionRequired = 5,
    SourceDisclosureRequired = 6,
    PatentClauseRisk = 7,
    CommercialRestriction = 8,
    ConditionalLicenseViolation = 9
}

public enum LicenseCategory
{
    Unknown = 0,
    Permissive = 1,
    WeakCopyleft = 2,
    StrongCopyleft = 3,
    Proprietary = 4,
    PublicDomain = 5
}

public enum LicenseObligationType
{
    Attribution = 0,
    SourceDisclosure = 1,
    PatentGrant = 2,
    TrademarkNotice = 3
}