4 files changed, 206 insertions, 0 deletions
diff --git a/backend/internal/analyzer/openai/openai.go b/backend/internal/analyzer/openai/openai.go
new file mode 100644
index 0000000..0419c57
--- /dev/null
+++ b/backend/internal/analyzer/openai/openai.go
@@ -0,0 +1,126 @@
+package openai
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"math"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/ansg191/ibd-trader-backend/internal/analyzer"
+	"github.com/ansg191/ibd-trader-backend/internal/utils"
+
+	"github.com/Rhymond/go-money"
+	"github.com/sashabaranov/go-openai"
+)
+
+type Client interface {
+	CreateChatCompletion(
+		ctx context.Context,
+		request openai.ChatCompletionRequest,
+	) (response openai.ChatCompletionResponse, err error)
+}
+
+type Analyzer struct {
+	client      Client
+	model       string
+	systemMsg   string
+	temperature float32
+}
+
+func NewAnalyzer(opts ...Option) *Analyzer {
+	a := &Analyzer{
+		client:      nil,
+		model:       defaultModel,
+		systemMsg:   defaultSystemMsg,
+		temperature: defaultTemperature,
+	}
+	for _, option := range opts {
+		option(a)
+	}
+	if a.client == nil {
+		panic("client is required")
+	}
+
+	return a
+}
+
+func (a *Analyzer) Analyze(
+	ctx context.Context,
+	symbol string,
+	price *money.Money,
+	rawAnalysis string,
+) (*analyzer.Analysis, error) {
+	usrMsg := fmt.Sprintf(
+		"%s\n%s\n%s\n%s\n",
+		time.Now().Format(time.RFC3339),
+		symbol,
+		price.Display(),
+		rawAnalysis,
+	)
+	res, err := a.client.CreateChatCompletion(ctx, openai.ChatCompletionRequest{
+		Model: a.model,
+		Messages: []openai.ChatCompletionMessage{
+			{
+				Role:    openai.ChatMessageRoleSystem,
+				Content: a.systemMsg,
+			},
+			{
+				Role:    openai.ChatMessageRoleUser,
+				Content: usrMsg,
+			},
+		},
+		MaxTokens:      0,
+		Temperature:    a.temperature,
+		ResponseFormat: &openai.ChatCompletionResponseFormat{Type: openai.ChatCompletionResponseFormatTypeJSONObject},
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	var resp response
+	if err = json.Unmarshal([]byte(res.Choices[0].Message.Content), &resp); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal gpt response: %w", err)
+	}
+
+	var action analyzer.ChartAction
+	switch strings.ToLower(resp.Action) {
+	case "buy":
+		action = analyzer.Buy
+	case "sell":
+		action = analyzer.Sell
+	case "hold":
+		action = analyzer.Hold
+	default:
+		action = analyzer.Unknown
+	}
+
+	m, err := utils.ParseMoney(resp.Price)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse price: %w", err)
+	}
+
+	confidence, err := strconv.ParseFloat(resp.Confidence, 64)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse confidence: %w", err)
+	}
+	if confidence < 0 || confidence > 100 {
+		return nil, fmt.Errorf("confidence must be between 0 and 100, got %f", confidence)
+	}
+
+	return &analyzer.Analysis{
+		Action:     action,
+		Price:      m,
+		Reason:     resp.Reason,
+		Confidence: uint8(math.Floor(confidence)),
+	}, nil
+}
+
+type response struct {
+	Action     string `json:"action"`
+	Price      string `json:"price"`
+	Reason     string `json:"reason"`
+	Confidence string `json:"confidence"`
+}
diff --git a/backend/internal/analyzer/openai/openai_test.go b/backend/internal/analyzer/openai/openai_test.go
new file mode 100644
index 0000000..0aac709
--- /dev/null
+++ b/backend/internal/analyzer/openai/openai_test.go
@@ -0,0 +1 @@
+package openai
diff --git a/backend/internal/analyzer/openai/options.go b/backend/internal/analyzer/openai/options.go
new file mode 100644
index 0000000..11d691f
--- /dev/null
+++ b/backend/internal/analyzer/openai/options.go
@@ -0,0 +1,45 @@
+package openai
+
+import (
+	_ "embed"
+
+	"github.com/sashabaranov/go-openai"
+)
+
+//go:embed system.txt
+var defaultSystemMsg string
+
+const defaultModel = openai.GPT4o
+const defaultTemperature = 0.25
+
+type Option func(*Analyzer)
+
+func WithClientConfig(cfg openai.ClientConfig) Option {
+	return func(a *Analyzer) {
+		a.client = openai.NewClientWithConfig(cfg)
+	}
+}
+
+func WithDefaultConfig(apiKey string) Option {
+	return func(a *Analyzer) {
+		a.client = openai.NewClient(apiKey)
+	}
+}
+
+func WithModel(model string) Option {
+	return func(a *Analyzer) {
+		a.model = model
+	}
+}
+
+func WithSystemMsg(msg string) Option {
+	return func(a *Analyzer) {
+		a.systemMsg = msg
+	}
+}
+
+func WithTemperature(temp float32) Option {
+	return func(a *Analyzer) {
+		a.temperature = temp
+	}
+}
diff --git a/backend/internal/analyzer/openai/system.txt b/backend/internal/analyzer/openai/system.txt
new file mode 100644
index 0000000..82e3b2a
--- /dev/null
+++ b/backend/internal/analyzer/openai/system.txt
@@ -0,0 +1,34 @@
+You're a stock analyzer.
+You will be given a stock symbol, its current price, and its chart analysis.
+Your job is to determine the best course of action to do with the stock (buy, sell, hold, or unknown),
+the price at which the action should be taken, the reason for the action, and the confidence (0-100)
+level you have in the action.
+
+The reason should be a paragraph explaining why you chose the action.
+
+The date the chart analysis was done may be mentioned in the chart analysis.
+Make sure to take that into account when making your decision.
+If the chart analysis is older than 1 week, lower your confidence accordingly and mention that in the reason.
+If the chart analysis is too outdated, set the action to "unknown".
+
+The information will be given in the following format:
+```
+<current datetime>
+<stock symbol>
+<current price>
+<chart analysis>
+```
+
+Your response should be in the following JSON format:
+```
+{
+    "action": "<action>",
+    "price": "<price>",
+    "reason": "<reason>",
+    "confidence": "<confidence>"
+}
+```
+All fields are required and must be strings.
+`action` must be one of the following: "buy", "sell", "hold", or "unknown".
+`price` must contain the symbol for the currency and the price (e.g. "$100").
+The system WILL validate your response.
+\ No newline at end of file