@spec standardize_history_schema(
  Explorer.DataFrame.t(),
  keyword()
) :: {:ok, Explorer.DataFrame.t()} | {:error, term()}

Standardizes historical data DataFrame to consistent schema.

Standard Historical Data Schema

• symbol (string): Stock/crypto symbol
• timestamp (datetime): UTC timestamp with timezone info
• open (f64): Opening price
• high (f64): Highest price
• low (f64): Lowest price
• close (f64): Closing price
• volume (s64): Trading volume
• adj_close (f64): Adjusted closing price (when available)
• market_cap (f64): Market capitalization (crypto only)
• provider (string): Data source provider
• currency (string): Price currency
• timezone (string): Original timezone

@spec standardize_params(
  keyword(),
  atom()
) :: {:ok, keyword()} | {:error, term()}

Standardizes query parameters across all providers.

Standard Parameters

• :interval - Time interval: "1m", "5m", "15m", "30m", "1h", "1d", "1w", "1mo"
• :period - Time period: "1d", "5d", "1mo", "3mo", "6mo", "1y", "2y", "5y", "10y", "max"
• :limit - Number of data points to return (integer)
• :start_date - Start date (Date, DateTime, or ISO string)
• :end_date - End date (Date, DateTime, or ISO string)
• :currency - Base currency for crypto quotes: "usd", "eur", "btc", "eth"
• :adjusted - Whether to use adjusted prices (boolean, default: true)
• :api_key - API key for authentication

Returns

{:ok, standardized_params} or {:error, reason}

@spec standardize_quote_schema(
  Explorer.DataFrame.t(),
  keyword()
) :: {:ok, Explorer.DataFrame.t()} | {:error, term()}

Standardizes quote data DataFrame to consistent schema.

Standard Quote Data Schema

• symbol (string): Stock/crypto symbol
• price (f64): Current price
• change (f64): Absolute price change
• change_percent (f64): Percentage change
• volume (s64): Current/24h volume
• high_24h (f64): 24-hour high price
• low_24h (f64): 24-hour low price
• market_cap (f64): Market capitalization (when available)
• timestamp (datetime): UTC timestamp
• provider (string): Data source provider
• currency (string): Quote currency
• market_state (string): Market state (open/closed/pre/post)

@spec standardize_search_schema(
  Explorer.DataFrame.t(),
  keyword()
) :: {:ok, Explorer.DataFrame.t()} | {:error, term()}

Standardizes search results DataFrame to consistent schema.

Standard Search Results Schema

• symbol (string): Trading symbol
• name (string): Full company/asset name
• type (string): Asset type (stock, etf, crypto, forex, index)
• exchange (string): Primary exchange
• currency (string): Trading currency
• country (string): Country/region
• sector (string): Business sector (when available)
• industry (string): Industry classification (when available)
• market_cap (f64): Market capitalization (when available)
• provider (string): Data source provider
• match_score (f64): Search relevance score (0.0 - 1.0)

@spec supported_currencies() :: [String.t()]

Lists all supported currencies.

@spec supported_intervals() :: [String.t()]

Lists all supported standard intervals.

@spec supported_periods() :: [String.t()]

Lists all supported standard periods.

@spec validate_provider_support(
  keyword(),
  atom()
) :: :ok | {:error, term()}

Validates parameter compatibility with provider.