-- Authentication: users, API tokens, sessions, audit log, and user tracking columns
-- Migration: 009_auth
-- Date: 2026-01

BEGIN;

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-- Users
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CREATE TABLE users (
    id            UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    username      TEXT UNIQUE NOT NULL,
    display_name  TEXT NOT NULL DEFAULT '',
    email         TEXT,
    password_hash TEXT,                           -- NULL for LDAP/OIDC-only users
    auth_source   TEXT NOT NULL DEFAULT 'local',  -- 'local', 'ldap', 'oidc'
    oidc_subject  TEXT,                           -- Stable OIDC sub claim
    role          TEXT NOT NULL DEFAULT 'viewer',  -- 'admin', 'editor', 'viewer'
    is_active     BOOLEAN NOT NULL DEFAULT true,
    last_login_at TIMESTAMPTZ,
    created_at    TIMESTAMPTZ NOT NULL DEFAULT now(),
    updated_at    TIMESTAMPTZ NOT NULL DEFAULT now()
);

CREATE UNIQUE INDEX idx_users_oidc_subject ON users(oidc_subject) WHERE oidc_subject IS NOT NULL;
CREATE INDEX idx_users_username ON users(username);
CREATE INDEX idx_users_auth_source ON users(auth_source);
CREATE INDEX idx_users_role ON users(role);

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-- API Tokens
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CREATE TABLE api_tokens (
    id            UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    user_id       UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    name          TEXT NOT NULL,                  -- Human-readable label
    token_hash    TEXT UNIQUE NOT NULL,           -- SHA-256 of raw token
    token_prefix  TEXT NOT NULL,                  -- First 13 chars for display (silo_ + 8 hex)
    scopes        TEXT[] NOT NULL DEFAULT '{}',   -- Reserved for future fine-grained permissions
    last_used_at  TIMESTAMPTZ,
    expires_at    TIMESTAMPTZ,                    -- NULL = never expires
    created_at    TIMESTAMPTZ NOT NULL DEFAULT now()
);

CREATE INDEX idx_api_tokens_user ON api_tokens(user_id);
CREATE INDEX idx_api_tokens_hash ON api_tokens(token_hash);

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-- Sessions (schema required by alexedwards/scs pgxstore)
--------------------------------------------------------------------------------

CREATE TABLE sessions (
    token  TEXT PRIMARY KEY,
    data   BYTEA NOT NULL,
    expiry TIMESTAMPTZ NOT NULL
);

CREATE INDEX idx_sessions_expiry ON sessions(expiry);

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-- Audit Log
--------------------------------------------------------------------------------

CREATE TABLE audit_log (
    id            UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    timestamp     TIMESTAMPTZ NOT NULL DEFAULT now(),
    user_id       UUID REFERENCES users(id) ON DELETE SET NULL,
    username      TEXT NOT NULL,
    action        TEXT NOT NULL,                  -- 'create', 'update', 'delete', 'login', etc.
    resource_type TEXT NOT NULL,                  -- 'item', 'revision', 'project', 'relationship'
    resource_id   TEXT NOT NULL,
    details       JSONB,
    ip_address    TEXT
);

CREATE INDEX idx_audit_log_timestamp ON audit_log(timestamp DESC);
CREATE INDEX idx_audit_log_user ON audit_log(username);
CREATE INDEX idx_audit_log_resource ON audit_log(resource_type, resource_id);

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-- Add user tracking columns to existing tables
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-- Items: track who created and last updated
ALTER TABLE items ADD COLUMN created_by TEXT;
ALTER TABLE items ADD COLUMN updated_by TEXT;

-- Relationships/BOM: track who created and last updated
ALTER TABLE relationships ADD COLUMN created_by TEXT;
ALTER TABLE relationships ADD COLUMN updated_by TEXT;

-- Projects: track who created
ALTER TABLE projects ADD COLUMN created_by TEXT;

-- Sync log: track who triggered the sync
ALTER TABLE sync_log ADD COLUMN triggered_by TEXT;

COMMIT;