package ice

import (
    "context"
    "fmt"
    "strings"

    "ai-agent/internal/llm"
    "ai-agent/internal/memory"
)

var autoMemorySystemPrompt = "Extract any important facts, user preferences, decisions, or action items from this exchange.\n" +
    "Output one item per line in the format: TYPE: content\n" +
    "Where TYPE is one of: FACT, DECISION, PREFERENCE, TODO\n" +
    "If there is nothing worth remembering, output exactly: NONE"

var autoMemoryUserTemplate = "User: %s\nAssistant: %s"

type AutoMemory struct {
    client   llm.Client
    memStore *memory.Store
}

func (am *AutoMemory) Detect(ctx context.Context, userMsg, assistantMsg string) error {
    if am.memStore == nil {
        return nil
    }
    if len(userMsg) < 20 && len(assistantMsg) < 50 {
        return nil
    }
    prompt := fmt.Sprintf(autoMemoryUserTemplate, userMsg, assistantMsg)
    var response strings.Builder
    err := am.client.ChatStream(ctx, llm.ChatOptions{
        System: autoMemorySystemPrompt,
        Messages: []llm.Message{
            {Role: "user", Content: prompt},
        },
    }, func(chunk llm.StreamChunk) error {
        response.WriteString(chunk.Text)
        return nil
    })
    if err != nil {
        return fmt.Errorf("auto-memory LLM call: %w", err)
    }
    return am.parseAndSave(response.String())
}

func (am *AutoMemory) parseAndSave(response string) error {
    lines := strings.Split(strings.TrimSpace(response), "\n")
    for _, line := range lines {
        line = strings.TrimSpace(line)
        if line == "" || strings.EqualFold(line, "NONE") {
            continue
        }
        parts := strings.SplitN(line, ": ", 2)
        if len(parts) != 2 {
            continue
        }
        typeName := strings.TrimSpace(parts[0])
        content := strings.TrimSpace(parts[1])
        if content == "" {
            continue
        }
        tag := strings.ToLower(typeName)
        switch tag {
        case "fact", "decision", "preference", "todo":
            // Valid type.
        default:
            continue
        }
        if _, err := am.memStore.Save(content, []string{tag, "auto"}); err != nil {
            return fmt.Errorf("save auto-memory: %w", err)
        }
    }
    return nil
}