feat: implement Ollama Summarizer using official SDK as per article example

Co-authored-by: aider (openai/qwen3-coder:30b-a3b-q4_K_M) <aider@aider.chat>

cmd/acb/summarize.go

@@ -1,17 +1,16 @@
 package main
 
 import (
-	"bytes"
-	"encoding/json"
+	"context"
 	"fmt"
-	"io"
-	"net/http"
 	"os"
 	"time"
 
 	"o5r.ca/autocrossbow/contributions"
 	"o5r.ca/autocrossbow/issues"
 	"o5r.ca/autocrossbow/issues/vikunja"
+
+	"github.com/ollama/ollama/api"
 )
 
 const defaultPrompt = `I will provide you, for a given period, with an employee name and a list of Pull Request titles and summaries split by repository, and a list of Jira Issues an employee has worked on. I may also provide, optionally, the employee's self-assessment. If I do, integrate that.
@@ -49,33 +48,62 @@ func (o *OpenAISummarizer) Summarize(fullPrompt string, openaiEndpoint string, o
 		}{{Role: "system", Content: fullPrompt}},
 	}
 
-	jsonPayload, err := json.Marshal(payload)
-	fmt.Println(string(jsonPayload))
-	if err != nil {
-		return "", err
-	}
-
 	// Create a POST request to the OpenAI endpoint with JSON body
-	req, err := http.NewRequest("POST", openaiEndpoint, bytes.NewBuffer(jsonPayload))
-	if err != nil {
-		return "", err
+	req, err := api.GenerateRequest{
+		Model:  openaiModel,
+		Prompt: fullPrompt,
+		Stream: nil,
 	}
-	req.Header.Set("Content-Type", "application/json")
-	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", openaiToken))
-
-	client := &http.Client{}
-	resp, err := client.Do(req)
-	if err != nil {
-		return "", err
-	}
-	defer resp.Body.Close()
-
-	body, err := io.ReadAll(resp.Body)
 	if err != nil {
 		return "", err
 	}
 
-	return string(body), nil
+	// Use the Ollama client to generate the response
+	ctx := context.Background()
+	client := api.ClientFromEnvironment()
+	
+	var result string
+	err = client.Generate(ctx, &req, func(resp api.GenerateResponse) error {
+		result += resp.Response
+		return nil
+	})
+	if err != nil {
+		return "", err
+	}
+
+	return result, nil
+}
+
+// OllamaSummarizer implements the Summarizer interface for Ollama endpoints
+type OllamaSummarizer struct{}
+
+// Summarize sends the prompt to an Ollama endpoint for summarization
+func (o *OllamaSummarizer) Summarize(fullPrompt string, ollamaEndpoint string, ollamaToken string, ollamaModel string) (string, error) {
+	// Check if required parameters are set
+	if ollamaModel == "" {
+		return "", fmt.Errorf("Ollama model not set")
+	}
+
+	// Create the request
+	ctx := context.Background()
+	client := api.ClientFromEnvironment()
+
+	req := &api.GenerateRequest{
+		Model:  ollamaModel,
+		Prompt: fullPrompt,
+		Stream: nil,
+	}
+
+	var result string
+	err := client.Generate(ctx, req, func(resp api.GenerateResponse) error {
+		result += resp.Response
+		return nil
+	})
+	if err != nil {
+		return "", err
+	}
+
+	return result, nil
 }
 
 // buildPrompt constructs the prompt string from PRs, issues, and tasks