package httpapi

import (
	"encoding/json"
	"errors"
	"net/http"
	"strings"

	"github.com/easyai/easyai-ai-gateway/apps/api/internal/store"
)

// listRuntimePolicySets godoc
// @Summary 列出运行策略集
// @Description 管理端返回可分配给平台、模型或用户组的运行策略集。
// @Tags runtime
// @Produce json
// @Security BearerAuth
// @Success 200 {object} RuntimePolicySetListResponse
// @Failure 401 {object} ErrorEnvelope
// @Failure 403 {object} ErrorEnvelope
// @Failure 500 {object} ErrorEnvelope
// @Router /api/admin/runtime/policy-sets [get]
func (s *Server) listRuntimePolicySets(w http.ResponseWriter, r *http.Request) {
	items, err := s.store.ListRuntimePolicySets(r.Context())
	if err != nil {
		s.logger.Error("list runtime policy sets failed", "error", err)
		writeError(w, http.StatusInternalServerError, "list runtime policy sets failed")
		return
	}
	writeJSON(w, http.StatusOK, map[string]any{"items": items})
}

// getRunnerPolicy godoc
// @Summary 获取 Runner 策略
// @Description 管理端获取当前生效的默认 Runner 调度策略。
// @Tags runtime
// @Produce json
// @Security BearerAuth
// @Success 200 {object} store.RunnerPolicy
// @Failure 401 {object} ErrorEnvelope
// @Failure 403 {object} ErrorEnvelope
// @Failure 500 {object} ErrorEnvelope
// @Router /api/admin/runtime/runner-policy [get]
func (s *Server) getRunnerPolicy(w http.ResponseWriter, r *http.Request) {
	item, err := s.store.GetActiveRunnerPolicy(r.Context())
	if err != nil {
		s.logger.Error("get runner policy failed", "error", err)
		writeError(w, http.StatusInternalServerError, "get runner policy failed")
		return
	}
	writeJSON(w, http.StatusOK, item)
}

// updateRunnerPolicy godoc
// @Summary 更新 Runner 策略
// @Description 管理端写入默认 Runner 调度策略。
// @Tags runtime
// @Accept json
// @Produce json
// @Security BearerAuth
// @Param input body store.RunnerPolicyInput true "Runner 策略请求"
// @Success 200 {object} store.RunnerPolicy
// @Failure 400 {object} ErrorEnvelope
// @Failure 401 {object} ErrorEnvelope
// @Failure 403 {object} ErrorEnvelope
// @Failure 500 {object} ErrorEnvelope
// @Router /api/admin/runtime/runner-policy [patch]
func (s *Server) updateRunnerPolicy(w http.ResponseWriter, r *http.Request) {
	var input store.RunnerPolicyInput
	if err := json.NewDecoder(r.Body).Decode(&input); err != nil {
		writeError(w, http.StatusBadRequest, "invalid json body")
		return
	}
	item, err := s.store.UpsertDefaultRunnerPolicy(r.Context(), input)
	if err != nil {
		s.logger.Error("update runner policy failed", "error", err)
		writeError(w, http.StatusInternalServerError, "update runner policy failed")
		return
	}
	writeJSON(w, http.StatusOK, item)
}

type updatePlatformDynamicPriorityRequest struct {
	DynamicPriority *int `json:"dynamicPriority" example:"10"`
	Reset           bool `json:"reset" example:"false"`
}

// updatePlatformDynamicPriority godoc
// @Summary 更新平台动态优先级
// @Description 管理端调整平台运行时动态优先级；reset 为 true 时清空动态值。
// @Tags runtime
// @Accept json
// @Produce json
// @Security BearerAuth
// @Param platformID path string true "平台 ID"
// @Param input body updatePlatformDynamicPriorityRequest true "动态优先级请求"
// @Success 200 {object} store.Platform
// @Failure 400 {object} ErrorEnvelope
// @Failure 401 {object} ErrorEnvelope
// @Failure 403 {object} ErrorEnvelope
// @Failure 404 {object} ErrorEnvelope
// @Failure 500 {object} ErrorEnvelope
// @Router /api/admin/platforms/{platformID}/dynamic-priority [patch]
func (s *Server) updatePlatformDynamicPriority(w http.ResponseWriter, r *http.Request) {
	var input updatePlatformDynamicPriorityRequest
	if err := json.NewDecoder(r.Body).Decode(&input); err != nil {
		writeError(w, http.StatusBadRequest, "invalid json body")
		return
	}
	var dynamicPriority *int
	if input.Reset {
		dynamicPriority = nil
	} else {
		if input.DynamicPriority == nil {
			writeError(w, http.StatusBadRequest, "dynamicPriority is required unless reset is true")
			return
		}
		if *input.DynamicPriority < 0 {
			writeError(w, http.StatusBadRequest, "dynamicPriority must be greater than or equal to 0")
			return
		}
		dynamicPriority = input.DynamicPriority
	}
	item, err := s.store.UpdatePlatformDynamicPriority(r.Context(), r.PathValue("platformID"), dynamicPriority)
	if err != nil {
		if store.IsNotFound(err) {
			writeError(w, http.StatusNotFound, "platform not found")
			return
		}
		s.logger.Error("update platform dynamic priority failed", "error", err)
		writeError(w, http.StatusInternalServerError, "update platform dynamic priority failed")
		return
	}
	writeJSON(w, http.StatusOK, item)
}

// createRuntimePolicySet godoc
// @Summary 创建运行策略集
// @Description 管理端创建运行策略集，policyKey 和 name 必填。
// @Tags runtime
// @Accept json
// @Produce json
// @Security BearerAuth
// @Param input body store.RuntimePolicySetInput true "运行策略集请求"
// @Success 201 {object} store.RuntimePolicySet
// @Failure 400 {object} ErrorEnvelope
// @Failure 401 {object} ErrorEnvelope
// @Failure 403 {object} ErrorEnvelope
// @Failure 409 {object} ErrorEnvelope
// @Failure 500 {object} ErrorEnvelope
// @Router /api/admin/runtime/policy-sets [post]
func (s *Server) createRuntimePolicySet(w http.ResponseWriter, r *http.Request) {
	var input store.RuntimePolicySetInput
	if err := json.NewDecoder(r.Body).Decode(&input); err != nil {
		writeError(w, http.StatusBadRequest, "invalid json body")
		return
	}
	if !validRuntimePolicyInput(input) {
		writeError(w, http.StatusBadRequest, "policyKey and name are required")
		return
	}
	item, err := s.store.CreateRuntimePolicySet(r.Context(), input)
	if err != nil {
		if store.IsUniqueViolation(err) {
			writeError(w, http.StatusConflict, "runtime policy key already exists")
			return
		}
		s.logger.Error("create runtime policy set failed", "error", err)
		writeError(w, http.StatusInternalServerError, "create runtime policy set failed")
		return
	}
	writeJSON(w, http.StatusCreated, item)
}

// updateRuntimePolicySet godoc
// @Summary 更新运行策略集
// @Description 管理端更新运行策略集及其限流、重试、超时等策略配置。
// @Tags runtime
// @Accept json
// @Produce json
// @Security BearerAuth
// @Param policySetID path string true "运行策略集 ID"
// @Param input body store.RuntimePolicySetInput true "运行策略集请求"
// @Success 200 {object} store.RuntimePolicySet
// @Failure 400 {object} ErrorEnvelope
// @Failure 401 {object} ErrorEnvelope
// @Failure 403 {object} ErrorEnvelope
// @Failure 404 {object} ErrorEnvelope
// @Failure 409 {object} ErrorEnvelope
// @Failure 500 {object} ErrorEnvelope
// @Router /api/admin/runtime/policy-sets/{policySetID} [patch]
func (s *Server) updateRuntimePolicySet(w http.ResponseWriter, r *http.Request) {
	var input store.RuntimePolicySetInput
	if err := json.NewDecoder(r.Body).Decode(&input); err != nil {
		writeError(w, http.StatusBadRequest, "invalid json body")
		return
	}
	if !validRuntimePolicyInput(input) {
		writeError(w, http.StatusBadRequest, "policyKey and name are required")
		return
	}
	item, err := s.store.UpdateRuntimePolicySet(r.Context(), r.PathValue("policySetID"), input)
	if err != nil {
		if store.IsNotFound(err) {
			writeError(w, http.StatusNotFound, "runtime policy set not found")
			return
		}
		if store.IsUniqueViolation(err) {
			writeError(w, http.StatusConflict, "runtime policy key already exists")
			return
		}
		s.logger.Error("update runtime policy set failed", "error", err)
		writeError(w, http.StatusInternalServerError, "update runtime policy set failed")
		return
	}
	writeJSON(w, http.StatusOK, item)
}

// deleteRuntimePolicySet godoc
// @Summary 删除运行策略集
// @Description 管理端删除非默认运行策略集；默认策略集受保护。
// @Tags runtime
// @Produce json
// @Security BearerAuth
// @Param policySetID path string true "运行策略集 ID"
// @Success 204 "No Content"
// @Failure 401 {object} ErrorEnvelope
// @Failure 403 {object} ErrorEnvelope
// @Failure 404 {object} ErrorEnvelope
// @Failure 500 {object} ErrorEnvelope
// @Router /api/admin/runtime/policy-sets/{policySetID} [delete]
func (s *Server) deleteRuntimePolicySet(w http.ResponseWriter, r *http.Request) {
	if err := s.store.DeleteRuntimePolicySet(r.Context(), r.PathValue("policySetID")); err != nil {
		if store.IsNotFound(err) {
			writeError(w, http.StatusNotFound, "runtime policy set not found")
			return
		}
		if errors.Is(err, store.ErrProtectedDefault) {
			writeError(w, http.StatusForbidden, "default runtime policy set cannot be deleted")
			return
		}
		s.logger.Error("delete runtime policy set failed", "error", err)
		writeError(w, http.StatusInternalServerError, "delete runtime policy set failed")
		return
	}
	w.WriteHeader(http.StatusNoContent)
}

func validRuntimePolicyInput(input store.RuntimePolicySetInput) bool {
	return strings.TrimSpace(input.PolicyKey) != "" && strings.TrimSpace(input.Name) != ""
}