/*
Phase 21K illustration assignment audit fields.

Adds non-breaking persistence columns used by the forensic matcher to explain,
validate and safely invalidate illustration assignments. Existing rows remain
active and are backfilled with conservative defaults.
*/

IF COL_LENGTH(N'dbo.StoryIntelligenceCharacterIllustrationAssignments', N'ImportSessionID') IS NULL
    ALTER TABLE dbo.StoryIntelligenceCharacterIllustrationAssignments ADD ImportSessionID int NULL;

IF COL_LENGTH(N'dbo.StoryIntelligenceCharacterIllustrationAssignments', N'AssignmentStatus') IS NULL
    ALTER TABLE dbo.StoryIntelligenceCharacterIllustrationAssignments ADD AssignmentStatus nvarchar(40) NOT NULL CONSTRAINT DF_SICharacterIllustrationAssignments_AssignmentStatus DEFAULT N'Assigned';

IF COL_LENGTH(N'dbo.StoryIntelligenceCharacterIllustrationAssignments', N'AssignedUtc') IS NULL
    ALTER TABLE dbo.StoryIntelligenceCharacterIllustrationAssignments ADD AssignedUtc datetime2(0) NULL;

IF COL_LENGTH(N'dbo.StoryIntelligenceCharacterIllustrationAssignments', N'LastValidatedUtc') IS NULL
    ALTER TABLE dbo.StoryIntelligenceCharacterIllustrationAssignments ADD LastValidatedUtc datetime2(0) NULL;

IF COL_LENGTH(N'dbo.StoryIntelligenceCharacterIllustrationAssignments', N'InvalidatedUtc') IS NULL
    ALTER TABLE dbo.StoryIntelligenceCharacterIllustrationAssignments ADD InvalidatedUtc datetime2(0) NULL;

IF COL_LENGTH(N'dbo.StoryIntelligenceCharacterIllustrationAssignments', N'InvalidationReason') IS NULL
    ALTER TABLE dbo.StoryIntelligenceCharacterIllustrationAssignments ADD InvalidationReason nvarchar(500) NULL;

IF COL_LENGTH(N'dbo.StoryIntelligenceCharacterIllustrationAssignments', N'EvidenceVersion') IS NULL
    ALTER TABLE dbo.StoryIntelligenceCharacterIllustrationAssignments ADD EvidenceVersion nvarchar(40) NOT NULL CONSTRAINT DF_SICharacterIllustrationAssignments_EvidenceVersion DEFAULT N'21K';

IF COL_LENGTH(N'dbo.StoryIntelligenceCharacterIllustrationAssignments', N'IsFallback') IS NULL
    ALTER TABLE dbo.StoryIntelligenceCharacterIllustrationAssignments ADD IsFallback bit NOT NULL CONSTRAINT DF_SICharacterIllustrationAssignments_IsFallback DEFAULT 0;

EXEC(N'
UPDATE dbo.StoryIntelligenceCharacterIllustrationAssignments
SET AssignedUtc = COALESCE(AssignedUtc, CreatedUtc),
    LastValidatedUtc = COALESCE(LastValidatedUtc, UpdatedUtc),
    EvidenceVersion = COALESCE(NULLIF(EvidenceVersion, N''''), N''21K''),
    AssignmentStatus = COALESCE(NULLIF(AssignmentStatus, N''''), N''Assigned'')
WHERE AssignedUtc IS NULL
   OR LastValidatedUtc IS NULL
   OR NULLIF(EvidenceVersion, N'''') IS NULL
   OR NULLIF(AssignmentStatus, N'''') IS NULL;
');

IF NOT EXISTS (SELECT 1 FROM sys.indexes WHERE name = N'IX_SICharacterIllustrationAssignments_ImportSession' AND object_id = OBJECT_ID(N'dbo.StoryIntelligenceCharacterIllustrationAssignments'))
BEGIN
    EXEC(N'CREATE INDEX IX_SICharacterIllustrationAssignments_ImportSession
    ON dbo.StoryIntelligenceCharacterIllustrationAssignments(ImportSessionID, CharacterKey, IsActive)
    INCLUDE (IllustrationLibraryItemID, AssignmentStatus, IsFallback, LastValidatedUtc);');
END;

IF COL_LENGTH(N'dbo.StoryIntelligenceIllustrationDemands', N'QueuedUtc') IS NULL
    ALTER TABLE dbo.StoryIntelligenceIllustrationDemands ADD QueuedUtc datetime2(0) NULL;

IF COL_LENGTH(N'dbo.StoryIntelligenceIllustrationDemands', N'GenerationSource') IS NULL
    ALTER TABLE dbo.StoryIntelligenceIllustrationDemands ADD GenerationSource nvarchar(80) NOT NULL CONSTRAINT DF_StoryIntelligenceIllustrationDemands_GenerationSource DEFAULT N'Demand generation';