// common/proto/table_definition.proto
syntax = "proto3";
package komp_ac.table_definition;

import "common.proto";

// The TableDefinition service manages the entire lifecycle of user-defined
// tables (stored as both metadata and physical PostgreSQL tables) inside
// logical "profiles" (schemas). Each table has stored structure, links, and
// validation rules.
service TableDefinition {
  // Creates a new table (and schema if missing) with system columns,
  // linked-table foreign keys, user-defined columns, and optional indexes.
  // Also inserts metadata and default validation rules. Entirely transactional.
  rpc PostTableDefinition(PostTableDefinitionRequest) returns (TableDefinitionResponse);

  // Creates a regular user-table bundle from the restricted komp_ac_fields
  // contract embedded in a Typst invoice template. This is invoked explicitly
  // by the user; templates do not provision tables merely by existing.
  rpc CreateInvoiceTemplateTable(CreateInvoiceTemplateTableRequest) returns (CreateInvoiceTemplateTableResponse);

  // Appends new user-defined columns to an existing table.
  // Existing columns, links, and table logic are never changed by this call.
  rpc AddTableColumns(AddTableColumnsRequest) returns (TableDefinitionResponse);

  // Lists all profiles (schemas) and their tables with declared dependencies.
  // This provides a tree-like overview of table relationships.
  rpc GetProfileTree(komp_ac.common.Empty) returns (ProfileTreeResponse);

  // Fetches all tables with their columns and scripts for a specific profile.
  // Pure data retrieval - no business logic.
  rpc GetProfileDetails(GetProfileDetailsRequest) returns (GetProfileDetailsResponse);

  // Copies one complete profile into a new profile without copying table data.
  rpc CopyProfile(CopyProfileRequest) returns (CopyProfileResponse);

  // Returns the stored rename history for column aliases in one profile.
  rpc GetColumnAliasRenameHistory(GetColumnAliasRenameHistoryRequest) returns (GetColumnAliasRenameHistoryResponse);

  // Renames a user-visible column alias while keeping the physical column unchanged.
  rpc RenameColumnAlias(RenameColumnAliasRequest) returns (RenameColumnAliasResponse);

  // Drops a table and its metadata, then deletes the profile if it becomes empty.
  rpc DeleteTable(DeleteTableRequest) returns (DeleteTableResponse);
}

// A single link to another table within the same profile (schema).
message TableLink {
  // Name of an existing table within the same profile to link to.
  // For each link, a "<linked>_id" column is created on the new table.
  // That column references "<linked>"(id) and adds an index automatically.
  string linked_table_name = 1;

  // If true, the generated foreign key column is NOT NULL.
  // Otherwise the column allows NULL.
  // Duplicate links to the same target table in one request are rejected.
  bool required = 2;

  // User-defined column read from this linked row as the journal account.
  // Exactly one required link must set this when the table contains ACCOUNTING.
  string account_value_column = 3;
}

// Defines the input for creating a new table definition.
message PostTableDefinitionRequest {
  // Table name to create inside the target profile.
  // Must be lowercase, alphanumeric with underscores,
  // start with a letter, and be <= 63 chars.
  // Forbidden names: "id", "deleted", "created_at", "row_revision", or ending in "_id".
  string table_name = 1;

  // List of links (foreign keys) to existing tables in the same profile.
  // Each will automatically get a "<linked>_id" column and an index.
  repeated TableLink links = 2;

  // List of user-defined columns (adds to system/id/fk columns).
  repeated ColumnDefinition columns = 3;

  // List of column names to be indexed (must match existing user-defined columns).
  // Indexes can target only user-defined columns; system columns ("id", "deleted",
  // "created_at", "row_revision") and automatically generated foreign key ("*_id") columns already
  // have indexes. Requests trying to index those columns are rejected.
  repeated string indexes = 4;

  // Name of profile (Postgres schema) where the table will be created.
  // Same naming rules as table_name; cannot collide with reserved schemas
  // like "public", "information_schema", or ones starting with "pg_".
  string profile_name = 5;

  // ISO-4217 base currency used by every MONEY column in this table.
  string base_currency = 6;

  // Columns whose values identify a row to users in pickers, in the order
  // they are shown. Each must name one of the user-defined columns above.
  // Empty means the row is identified by its id alone.
  repeated string row_display_columns = 7;

  // ISO-4217 currency the profile keeps its accounting in. A profile is one
  // accounting entity and keeps one set of books, so this is required only when
  // the request creates the profile, and is ignored afterwards. It is unrelated
  // to base_currency: tables may hold money in any currency, and amounts convert
  // to this one when they reach the ledger.
  string accounting_currency = 8;
}

// Defines the input for explicitly creating a table backed by one invoice
// template. typst_source must contain exactly one declaration of the form:
//
//   #let komp_ac_fields = (
//     "invoice.number": (source: "local", field_type: "TEXT", write: "user"),
//     "items[].product": (source: "reference", table: "stock", required: true),
//     "items[].quantity": (source: "local", field_type: "DECIMAL(12,3)", write: "user"),
//     "items[].total": (source: "local", field_type: "MONEY", write: "script"),
//   )
//
// Root fields create columns and references on table_name. Every [] collection
// creates a child table with a required FK to its immediate parent; fields in
// that collection create columns and references on the child table. Multiple
// template paths in one scope may reuse the same reference.
message CreateInvoiceTemplateTableRequest {
  string profile_name = 1;
  string table_name = 2;
  string typst_source = 3;
  string base_currency = 4;
  repeated string row_display_columns = 5;
}

// One physical dynamic table created for an invoice template scope. The root
// has an empty collection_path and parent_table_name. Each [] scope names its
// collection and the generated table that owns those repeated rows.
message GeneratedInvoiceTemplateTable {
  string table_name = 1;
  string collection_path = 2;
  string parent_table_name = 3;
  string sql = 4;
}

// Reports the complete table bundle created from one invoice template.
message CreateInvoiceTemplateTableResponse {
  bool success = 1;
  repeated GeneratedInvoiceTemplateTable tables = 2;
}

// Defines append-only column additions for an existing table.
message AddTableColumnsRequest {
  // Existing profile/schema name.
  string profile_name = 1;

  // Existing table name in the profile.
  string table_name = 2;

  // New user-defined columns only. Existing columns cannot be changed here.
  repeated ColumnDefinition columns = 3;

  // Optional indexes for the new columns only.
  repeated string indexes = 4;

  // Required when adding the first MONEY column to a table.
  string base_currency = 5;

}

enum MoneyRounding {
  MONEY_ROUNDING_NONE = 0;
  MONEY_ROUNDING_HALF_UP = 1;
}

// Describes one user-defined column for a table.
message ColumnDefinition {
  // Column name that follows the same validation rules as table_name.
  // Must be lowercase, start with a letter, no uppercase characters,
  // and cannot be "id", "deleted", "created_at", "row_revision", or end with "_id".
  string name = 1;

  // Logical column type. Supported values (case-insensitive):
  //   TEXT
  //   BOOLEAN
  //   INSTANT (local input resolved in the authenticated user's timezone
  //            and displayed in the viewer timezone)
  //   USER_DATETIME (local input resolved in the user's timezone)
  //   RAW_DATETIME (timezone-free civil datetime)
  //   PHONE (international or national phone number; generates extension/type/country/calling-code companions)
  //   TIME (timezone-free time of day)
  //   MONEY (= unconstrained NUMERIC; currency comes from the table)
  //   ACCOUNTING (creates schema-managed name, debit, and credit columns;
  //               the table creator must separately provide a column named account
  //               with any supported type or a required link to a table named account;
  //               linked accounts post the linked row's configured display value;
  //               name is limited to 10 characters and one stored row contributes
  //               one line to the profile journal)
  //   INT
  //   BIGINT
  //   DATE
  //   DURATION
  //   PERIOD
  //   DECIMAL(p,s) → NUMERIC(p,s)
  // DECIMAL args must be integers (no sign, no dot, no leading zeros);
  // s ≤ p and p ≥ 1.
  string field_type = 2;

  reserved 3;

  // MONEY rounding applied before a value is stored.
  MoneyRounding rounding = 4;

  // When true, the submitted script result is validated normally and the
  // stored value is also refreshed when one of its dependencies later changes.
  bool recompute_on_dependency_change = 5;
}

// Response after table creation (success + DDL preview).
message TableDefinitionResponse {
  // True if all DB changes and metadata inserts succeeded.
  bool success = 1;

  // The actual SQL executed: CREATE TABLE + CREATE INDEX statements.
  string sql = 2;
}

// Describes the tree of all profiles and their tables.
message ProfileTreeResponse {
  // Table entry in a profile.
  message Table {
    // Internal ID from table_definitions.id (metadata record).
    int64 id = 1;

    // Table name within the profile (schema).
    string name = 2;

    // Other tables this one references (based on link definitions only).
    repeated string depends_on = 3;

    // Columns whose values make up the human-readable row label, in order.
    repeated string row_display_columns = 4;

    // "dynamic" for user-defined tables, "system" for backend-managed tables.
    string table_kind = 5;
  }

  // Profile (schema) entry.
  message Profile {
    // Name of the schema/profile (as stored in `schemas.name`).
    string name = 1;

    // All tables in that schema and their dependencies.
    repeated Table tables = 2;
  }

  // All profiles in the system.
  repeated Profile profiles = 1;
}

// Request to fetch all tables, columns and scripts for a profile.
message GetProfileDetailsRequest {
  // Profile (schema) name to fetch details for.
  string profile_name = 1;
}

// Response with all tables, columns and scripts for a profile.
message GetProfileDetailsResponse {
  string profile_name = 1;
  repeated TableDetail tables = 2;
}

// Request to copy one full profile into a new profile.
message CopyProfileRequest {
  string source_profile_name = 1;
  string target_profile_name = 2;
  repeated string table_names = 3;
}

// Response after copying a profile.
message CopyProfileResponse {
  bool success = 1;
  string message = 2;
  int32 tables_copied = 3;
  int32 scripts_copied = 4;
}

// Request to fetch recorded column alias rename history for one profile.
message GetColumnAliasRenameHistoryRequest {
  string profile_name = 1;

  // Filter. When omitted, returns all tables in the profile.
  optional int64 table_definition_id = 2;
}

// One recorded column alias rename.
message ColumnAliasRenameHistoryEntry {
  int64 id = 1;
  string profile_name = 2;
  int64 table_definition_id = 3;
  string table_name = 4;
  string old_column_name = 5;
  string new_column_name = 6;
  string created_at = 7;
}

// Response with stored column alias rename history rows.
message GetColumnAliasRenameHistoryResponse {
  string profile_name = 1;
  repeated ColumnAliasRenameHistoryEntry entries = 2;
}

// Describes a table with its columns and associated scripts.
message TableDetail {
  string name = 1;
  int64 id = 2;
  repeated ColumnDefinition columns = 3;
  repeated ScriptInfo scripts = 4;
  string base_currency = 5;
  repeated string row_display_columns = 6;
  map<string, ColumnBehavior> column_behaviors = 7;
  string table_kind = 8;
}

// Server-owned behavior for one logical column returned in table details.
message ColumnBehavior {
  // True when the server created the column as a companion of another column.
  bool generated = 1;

  // True when clients must display but never submit edits for the column.
  bool read_only = 2;

  // Logical source column name, empty for ordinary user-defined columns.
  string generated_from = 3;
}

// A script that targets a specific column in a table.
message ScriptInfo {
  int64 script_id = 1;
  string target_column = 2;
  string target_column_type = 3;
  string script = 4;
  string description = 5;
}

// Request to rename one user-visible column alias in a table.
message RenameColumnAliasRequest {
  string profile_name = 1;
  string table_name = 2;
  string old_column_name = 3;
  string new_column_name = 4;
}

// Response after renaming one column alias.
message RenameColumnAliasResponse {
  bool success = 1;
  string message = 2;
}

// Request to delete one table definition entirely.
message DeleteTableRequest {
  // Profile (schema) name owning the table (must exist).
  string profile_name = 1;

  // Table to drop (must exist in the profile).
  // Executes DROP TABLE "profile"."table" CASCADE and then removes metadata.
  string table_name = 2;
}

// Response after table deletion.
message DeleteTableResponse {
  // True if table and metadata were successfully deleted in one transaction.
  bool success = 1;

  // Human-readable summary of what was removed.
  string message = 2;
}