feat: initial release v0.3.0

- Support 9 chart types: line, bar, pie, scatter, bubble, donut, mixed, polar, radar
- Multi-format output: ANSI, SVG, PNG, Markdown
- Go + Fiber + gonum/plot
- Docker support
- Morandi color palette

internal/handler/chart.go

@@ -0,0 +1,96 @@
+package handler
+
+import (
+	"github.com/gofiber/fiber/v2"
+	"github.com/picoclaw/chart/internal/service"
+	"github.com/picoclaw/chart/internal/types"
+)
+
+type ChartHandler struct {
+	chartService *service.ChartService
+}
+
+func NewChartHandler(chartService *service.ChartService) *ChartHandler {
+	return &ChartHandler{
+		chartService: chartService,
+	}
+}
+
+func (h *ChartHandler) CreateChart(c *fiber.Ctx) error {
+	var req types.ChartRequest
+	if err := c.BodyParser(&req); err != nil {
+		return c.Status(fiber.StatusBadRequest).JSON(types.ErrorResponse{
+			Error: "invalid request body: " + err.Error(),
+		})
+	}
+
+	if req.Type == "" {
+		req.Type = types.ChartTypeLine
+	}
+
+	if len(req.Data.Datasets) == 0 {
+		return c.Status(fiber.StatusBadRequest).JSON(types.ErrorResponse{
+			Error: "datasets are required",
+		})
+	}
+
+	for _, dataset := range req.Data.Datasets {
+		if len(dataset.Values) == 0 {
+			return c.Status(fiber.StatusBadRequest).JSON(types.ErrorResponse{
+				Error: "dataset values cannot be empty",
+			})
+		}
+	}
+
+	resp, err := h.chartService.CreateChart(&req)
+	if err != nil {
+		return c.Status(fiber.StatusInternalServerError).JSON(types.ErrorResponse{
+			Error: err.Error(),
+		})
+	}
+
+	return c.Status(fiber.StatusCreated).JSON(resp)
+}
+
+func (h *ChartHandler) GetChart(c *fiber.Ctx) error {
+	id := c.Params("id")
+	if id == "" {
+		return c.Status(fiber.StatusBadRequest).JSON(types.ErrorResponse{
+			Error: "chart id is required",
+		})
+	}
+
+	chart, err := h.chartService.GetChart(id)
+	if err != nil {
+		return c.Status(fiber.StatusNotFound).JSON(types.ErrorResponse{
+			Error: err.Error(),
+		})
+	}
+
+	return c.Send(chart.SVG)
+}
+
+func (h *ChartHandler) GetChartPNG(c *fiber.Ctx) error {
+	id := c.Params("id")
+	if id == "" {
+		return c.Status(fiber.StatusBadRequest).JSON(types.ErrorResponse{
+			Error: "chart id is required",
+		})
+	}
+
+	pngData, err := h.chartService.GetChartPNG(id)
+	if err != nil {
+		return c.Status(fiber.StatusNotFound).JSON(types.ErrorResponse{
+			Error: err.Error(),
+		})
+	}
+
+	c.Set("Content-Type", "image/png")
+	return c.Send(pngData)
+}
+
+func (h *ChartHandler) Health(c *fiber.Ctx) error {
+	return c.JSON(fiber.Map{
+		"status": "ok",
+	})
+}