package db

import (
	"database/sql"
	"fmt"
)

// Migrate runs all database migrations
func Migrate(db *sql.DB) error {
	migrations := []string{
		createUsersTable,
		createEntriesTable,
		createAccessTable,
		createSessionsTable,
		createAuditLogTable,
		createIndexes,
	}

	for i, migration := range migrations {
		if _, err := db.Exec(migration); err != nil {
			return fmt.Errorf("migration %d failed: %w", i+1, err)
		}
	}

	return nil
}

const createUsersTable = `
CREATE TABLE IF NOT EXISTS users (
    id TEXT PRIMARY KEY,
    email TEXT UNIQUE NOT NULL,
    name TEXT NOT NULL,
    role TEXT NOT NULL CHECK (role IN ('admin', 'user')),
    avatar_url TEXT,
    created_at INTEGER NOT NULL,
    last_login INTEGER,
    is_active BOOLEAN NOT NULL DEFAULT 1
);`

const createEntriesTable = `
CREATE TABLE IF NOT EXISTS entries (
    id TEXT PRIMARY KEY,
    parent_id TEXT,
    deal_room_id TEXT NOT NULL,
    entry_type TEXT NOT NULL CHECK (entry_type IN ('deal_room', 'document', 'note', 'message', 'analysis')),
    title TEXT NOT NULL,
    content TEXT NOT NULL,
    file_path TEXT,
    file_size INTEGER,
    file_hash TEXT,
    embedding BLOB,
    created_by TEXT NOT NULL,
    created_at INTEGER NOT NULL,
    updated_at INTEGER NOT NULL,
    
    FOREIGN KEY (created_by) REFERENCES users(id),
    FOREIGN KEY (parent_id) REFERENCES entries(id),
    FOREIGN KEY (deal_room_id) REFERENCES entries(id)
);`

const createAccessTable = `
CREATE TABLE IF NOT EXISTS access (
    id TEXT PRIMARY KEY,
    entry_id TEXT NOT NULL,
    user_id TEXT NOT NULL,
    permissions INTEGER NOT NULL DEFAULT 1,
    granted_by TEXT NOT NULL,
    granted_at INTEGER NOT NULL,
    
    FOREIGN KEY (entry_id) REFERENCES entries(id) ON DELETE CASCADE,
    FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE,
    FOREIGN KEY (granted_by) REFERENCES users(id),
    
    UNIQUE(entry_id, user_id)
);`

const createSessionsTable = `
CREATE TABLE IF NOT EXISTS sessions (
    token TEXT PRIMARY KEY,
    user_id TEXT NOT NULL,
    expires_at INTEGER NOT NULL,
    created_at INTEGER NOT NULL,
    last_used INTEGER NOT NULL,
    user_agent TEXT,
    ip_address TEXT,
    
    FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
);`

const createAuditLogTable = `
CREATE TABLE IF NOT EXISTS audit_log (
    id TEXT PRIMARY KEY,
    user_id TEXT,
    entry_id TEXT,
    action TEXT NOT NULL,
    details TEXT,
    ip_address TEXT,
    user_agent TEXT,
    created_at INTEGER NOT NULL,
    
    FOREIGN KEY (user_id) REFERENCES users(id),
    FOREIGN KEY (entry_id) REFERENCES entries(id)
);`

const createIndexes = `
CREATE INDEX IF NOT EXISTS idx_users_email ON users(email);
CREATE INDEX IF NOT EXISTS idx_users_active ON users(is_active);

CREATE INDEX IF NOT EXISTS idx_entries_deal_room ON entries(deal_room_id);
CREATE INDEX IF NOT EXISTS idx_entries_type ON entries(entry_type);
CREATE INDEX IF NOT EXISTS idx_entries_parent ON entries(parent_id);
CREATE INDEX IF NOT EXISTS idx_entries_created ON entries(created_at);
CREATE INDEX IF NOT EXISTS idx_entries_creator ON entries(created_by);

CREATE INDEX IF NOT EXISTS idx_access_entry ON access(entry_id);
CREATE INDEX IF NOT EXISTS idx_access_user ON access(user_id);
CREATE INDEX IF NOT EXISTS idx_access_permissions ON access(permissions);

CREATE INDEX IF NOT EXISTS idx_sessions_user ON sessions(user_id);
CREATE INDEX IF NOT EXISTS idx_sessions_expires ON sessions(expires_at);

CREATE INDEX IF NOT EXISTS idx_audit_user ON audit_log(user_id);
CREATE INDEX IF NOT EXISTS idx_audit_entry ON audit_log(entry_id);
CREATE INDEX IF NOT EXISTS idx_audit_action ON audit_log(action);
CREATE INDEX IF NOT EXISTS idx_audit_created ON audit_log(created_at);`