ollama_summarizer

-module(ollama_summarizer).
-author("Steve Roques").

%% Public API

-export([

    summarize_url/1, summarize_url/2,

    summarize_html/1, summarize_html/2,

    summarize/1, summarize/2,

    print_result/1,

    default_config/0,

    get_env_config/0

]).

%% =============================================================================

%% Main summarization functions

%% =============================================================================


%% Summarize a web page by URL using environment/default config.

summarize_url(Url) ->
    summarize_url(Url, get_env_config()).

%% Summarize a web page by URL using a custom config.

summarize_url(Url, Config) ->
    case fetch_html(Url) of
        {ok, Html} -> summarize_html(Html, Config);
        {error, Reason} -> {error, {fetch_failed, Reason}}
    end.

%% Summarize HTML content using environment/default config.

summarize_html(Html) ->
    summarize_html(Html, get_env_config()).

%% Summarize HTML content using a custom config.

summarize_html(Html, Config) ->
    Text = extract_text_from_html(Html),
    summarize(Text, Config).

%% Summarize plain text using environment/default config.

summarize(Text) ->
    summarize(Text, get_env_config()).

%% Summarize plain text using a custom config.

summarize(Text, Config) ->
    %% Build the prompt using the template from config or default

    PromptTemplate = maps:get(prompt_template, Config, default_prompt_template()),
    Prompt = ollama_handler:format_prompt(PromptTemplate, [Text]),
    %% Delegate to ollama_handler with the full config

    ollama_handler:generate(Prompt, Config).

%% =============================================================================

%% Configuration helpers

%% =============================================================================


%% Returns the default config (handler defaults + our default prompt template).

default_config() ->
    maps:merge(
        ollama_handler:default_config(),
        #{prompt_template => default_prompt_template()}
    ).

%% Returns config from environment variables, falling back to defaults.

get_env_config() ->
    maps:merge(
        ollama_handler:get_env_config(),
        #{prompt_template => os:getenv("OLLAMA_PROMPT", default_prompt_template())}
    ).

%% The default prompt template for summarization.

default_prompt_template() ->
    "IMPORTANT : Résume ce contenu en français en quelques phrases claires et concises:\n\n~s".

%% =============================================================================

%% Utility functions

%% =============================================================================


%% Print the result of a summarization operation.

print_result(Result) ->
    ollama_handler:print_result(Result).

%% Fetch HTML content from a URL.

fetch_html(Url) ->
    application:ensure_all_started(inets),
    case httpc:request(get, {Url, []}, [], []) of
        {ok, {{_, 200, _}, _, Body}} -> {ok, Body};
        {ok, {{_, Code, _}, _, _}} -> {error, {http_error, Code}};
        {error, Reason} -> {error, Reason}
    end.

%% Extract plain text from HTML by removing tags and normalizing whitespace.

extract_text_from_html(Html) ->
    NoTags = re:replace(Html, "<[^>]*>", " ", [global, {return, list}]),
    CleanSpaces = re:replace(NoTags, "\\s+", " ", [global, {return, list}]),
    string:strip(CleanSpaces).