package rest

import (
	"bytes"
	"context"
	"encoding/json"
	"io"
	"net/http"
	"strconv"
	"strings"

	"github.com/netbirdio/netbird/shared/management/http/api"
)

// AgentNetworkAPI APIs for the Agent Network (AI/LLM gateway), do not use directly
// see more: https://docs.netbird.io/api/resources/agent-network
type AgentNetworkAPI struct {
	c *Client
}

// ListCatalogProviders lists the catalog of supported upstream AI providers
// (openai_api, anthropic_api, bedrock_api, ...) with their default models and
// pricing, used to prefill provider create forms.
func (a *AgentNetworkAPI) ListCatalogProviders(ctx context.Context) ([]api.AgentNetworkCatalogProvider, error) {
	resp, err := a.c.NewRequest(ctx, "GET", "/api/agent-network/catalog/providers", nil, nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[[]api.AgentNetworkCatalogProvider](resp)
	return ret, err
}

// ListProviders lists all Agent Network providers
func (a *AgentNetworkAPI) ListProviders(ctx context.Context) ([]api.AgentNetworkProvider, error) {
	resp, err := a.c.NewRequest(ctx, "GET", "/api/agent-network/providers", nil, nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[[]api.AgentNetworkProvider](resp)
	return ret, err
}

// GetProvider gets Agent Network provider info
func (a *AgentNetworkAPI) GetProvider(ctx context.Context, providerID string) (*api.AgentNetworkProvider, error) {
	resp, err := a.c.NewRequest(ctx, "GET", "/api/agent-network/providers/"+providerID, nil, nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[api.AgentNetworkProvider](resp)
	return &ret, err
}

// CreateProvider creates a new Agent Network provider. Providers have no
// settings side effects — bootstrap the account's gateway endpoint separately
// via CreateSettings.
func (a *AgentNetworkAPI) CreateProvider(ctx context.Context, request api.PostApiAgentNetworkProvidersJSONRequestBody) (*api.AgentNetworkProvider, error) {
	requestBytes, err := json.Marshal(request)
	if err != nil {
		return nil, err
	}
	resp, err := a.c.NewRequest(ctx, "POST", "/api/agent-network/providers", bytes.NewReader(requestBytes), nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[api.AgentNetworkProvider](resp)
	return &ret, err
}

// UpdateProvider updates an Agent Network provider. The request replaces the
// provider's mutable state; only an omitted api_key keeps the stored key
// (secrets are never required to round-trip).
func (a *AgentNetworkAPI) UpdateProvider(ctx context.Context, providerID string, request api.PutApiAgentNetworkProvidersProviderIdJSONRequestBody) (*api.AgentNetworkProvider, error) {
	requestBytes, err := json.Marshal(request)
	if err != nil {
		return nil, err
	}
	resp, err := a.c.NewRequest(ctx, "PUT", "/api/agent-network/providers/"+providerID, bytes.NewReader(requestBytes), nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[api.AgentNetworkProvider](resp)
	return &ret, err
}

// DeleteProvider deletes an Agent Network provider. Fails while any policy
// still references the provider — detach it first.
func (a *AgentNetworkAPI) DeleteProvider(ctx context.Context, providerID string) error {
	resp, err := a.c.NewRequest(ctx, "DELETE", "/api/agent-network/providers/"+providerID, nil, nil)
	if err != nil {
		return err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}

	return nil
}

// ListPolicies lists all Agent Network policies
func (a *AgentNetworkAPI) ListPolicies(ctx context.Context) ([]api.AgentNetworkPolicy, error) {
	resp, err := a.c.NewRequest(ctx, "GET", "/api/agent-network/policies", nil, nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[[]api.AgentNetworkPolicy](resp)
	return ret, err
}

// GetPolicy gets Agent Network policy info
func (a *AgentNetworkAPI) GetPolicy(ctx context.Context, policyID string) (*api.AgentNetworkPolicy, error) {
	resp, err := a.c.NewRequest(ctx, "GET", "/api/agent-network/policies/"+policyID, nil, nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[api.AgentNetworkPolicy](resp)
	return &ret, err
}

// CreatePolicy creates a new Agent Network policy
func (a *AgentNetworkAPI) CreatePolicy(ctx context.Context, request api.PostApiAgentNetworkPoliciesJSONRequestBody) (*api.AgentNetworkPolicy, error) {
	requestBytes, err := json.Marshal(request)
	if err != nil {
		return nil, err
	}
	resp, err := a.c.NewRequest(ctx, "POST", "/api/agent-network/policies", bytes.NewReader(requestBytes), nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[api.AgentNetworkPolicy](resp)
	return &ret, err
}

// UpdatePolicy updates an Agent Network policy
func (a *AgentNetworkAPI) UpdatePolicy(ctx context.Context, policyID string, request api.PutApiAgentNetworkPoliciesPolicyIdJSONRequestBody) (*api.AgentNetworkPolicy, error) {
	requestBytes, err := json.Marshal(request)
	if err != nil {
		return nil, err
	}
	resp, err := a.c.NewRequest(ctx, "PUT", "/api/agent-network/policies/"+policyID, bytes.NewReader(requestBytes), nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[api.AgentNetworkPolicy](resp)
	return &ret, err
}

// DeletePolicy deletes an Agent Network policy
func (a *AgentNetworkAPI) DeletePolicy(ctx context.Context, policyID string) error {
	resp, err := a.c.NewRequest(ctx, "DELETE", "/api/agent-network/policies/"+policyID, nil, nil)
	if err != nil {
		return err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}

	return nil
}

// ListGuardrails lists all Agent Network guardrails
func (a *AgentNetworkAPI) ListGuardrails(ctx context.Context) ([]api.AgentNetworkGuardrail, error) {
	resp, err := a.c.NewRequest(ctx, "GET", "/api/agent-network/guardrails", nil, nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[[]api.AgentNetworkGuardrail](resp)
	return ret, err
}

// GetGuardrail gets Agent Network guardrail info
func (a *AgentNetworkAPI) GetGuardrail(ctx context.Context, guardrailID string) (*api.AgentNetworkGuardrail, error) {
	resp, err := a.c.NewRequest(ctx, "GET", "/api/agent-network/guardrails/"+guardrailID, nil, nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[api.AgentNetworkGuardrail](resp)
	return &ret, err
}

// CreateGuardrail creates a new Agent Network guardrail
func (a *AgentNetworkAPI) CreateGuardrail(ctx context.Context, request api.PostApiAgentNetworkGuardrailsJSONRequestBody) (*api.AgentNetworkGuardrail, error) {
	requestBytes, err := json.Marshal(request)
	if err != nil {
		return nil, err
	}
	resp, err := a.c.NewRequest(ctx, "POST", "/api/agent-network/guardrails", bytes.NewReader(requestBytes), nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[api.AgentNetworkGuardrail](resp)
	return &ret, err
}

// UpdateGuardrail updates an Agent Network guardrail
func (a *AgentNetworkAPI) UpdateGuardrail(ctx context.Context, guardrailID string, request api.PutApiAgentNetworkGuardrailsGuardrailIdJSONRequestBody) (*api.AgentNetworkGuardrail, error) {
	requestBytes, err := json.Marshal(request)
	if err != nil {
		return nil, err
	}
	resp, err := a.c.NewRequest(ctx, "PUT", "/api/agent-network/guardrails/"+guardrailID, bytes.NewReader(requestBytes), nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[api.AgentNetworkGuardrail](resp)
	return &ret, err
}

// DeleteGuardrail deletes an Agent Network guardrail
func (a *AgentNetworkAPI) DeleteGuardrail(ctx context.Context, guardrailID string) error {
	resp, err := a.c.NewRequest(ctx, "DELETE", "/api/agent-network/guardrails/"+guardrailID, nil, nil)
	if err != nil {
		return err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}

	return nil
}

// ListBudgetRules lists all account-level Agent Network budget rules
func (a *AgentNetworkAPI) ListBudgetRules(ctx context.Context) ([]api.AgentNetworkBudgetRule, error) {
	resp, err := a.c.NewRequest(ctx, "GET", "/api/agent-network/budget-rules", nil, nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[[]api.AgentNetworkBudgetRule](resp)
	return ret, err
}

// GetBudgetRule gets Agent Network budget rule info
func (a *AgentNetworkAPI) GetBudgetRule(ctx context.Context, ruleID string) (*api.AgentNetworkBudgetRule, error) {
	resp, err := a.c.NewRequest(ctx, "GET", "/api/agent-network/budget-rules/"+ruleID, nil, nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[api.AgentNetworkBudgetRule](resp)
	return &ret, err
}

// CreateBudgetRule creates a new Agent Network budget rule
func (a *AgentNetworkAPI) CreateBudgetRule(ctx context.Context, request api.PostApiAgentNetworkBudgetRulesJSONRequestBody) (*api.AgentNetworkBudgetRule, error) {
	requestBytes, err := json.Marshal(request)
	if err != nil {
		return nil, err
	}
	resp, err := a.c.NewRequest(ctx, "POST", "/api/agent-network/budget-rules", bytes.NewReader(requestBytes), nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[api.AgentNetworkBudgetRule](resp)
	return &ret, err
}

// UpdateBudgetRule updates an Agent Network budget rule
func (a *AgentNetworkAPI) UpdateBudgetRule(ctx context.Context, ruleID string, request api.PutApiAgentNetworkBudgetRulesRuleIdJSONRequestBody) (*api.AgentNetworkBudgetRule, error) {
	requestBytes, err := json.Marshal(request)
	if err != nil {
		return nil, err
	}
	resp, err := a.c.NewRequest(ctx, "PUT", "/api/agent-network/budget-rules/"+ruleID, bytes.NewReader(requestBytes), nil)
	if err != nil {
		return nil, err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[api.AgentNetworkBudgetRule](resp)
	return &ret, err
}

// DeleteBudgetRule deletes an Agent Network budget rule
func (a *AgentNetworkAPI) DeleteBudgetRule(ctx context.Context, ruleID string) error {
	resp, err := a.c.NewRequest(ctx, "DELETE", "/api/agent-network/budget-rules/"+ruleID, nil, nil)
	if err != nil {
		return err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}

	return nil
}

// GetSettings gets the account's Agent Network gateway settings (endpoint,
// proxy address, collection toggles). An account that has not been
// bootstrapped yet — via CreateSettings — reads as the defaults with an empty
// Endpoint and ProxyAddress. Management servers prior to that contract
// answered 200 with a JSON null body instead; that legacy shape is translated
// to an APIError matchable via IsNotFound rather than fabricating defaults
// the server never stated.
func (a *AgentNetworkAPI) GetSettings(ctx context.Context) (*api.AgentNetworkSettings, error) {
	settings, _, err := a.GetSettingsWithETag(ctx)
	return settings, err
}

// GetSettingsWithETag is GetSettings, additionally returning the entity-tag
// the server derived for the settings it returned. Hand that validator to
// UpdateSettingsIfMatch or DeleteSettingsIfMatch to make the write conditional
// on nothing having changed in between — the read-modify-write cycle that
// otherwise silently reverts a concurrent change.
func (a *AgentNetworkAPI) GetSettingsWithETag(ctx context.Context) (*api.AgentNetworkSettings, string, error) {
	resp, err := a.c.NewRequest(ctx, "GET", "/api/agent-network/settings", nil, nil)
	if err != nil {
		return nil, "", err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, "", err
	}
	if trimmed := bytes.TrimSpace(body); len(trimmed) == 0 || bytes.Equal(trimmed, []byte("null")) {
		return nil, "", &APIError{StatusCode: http.StatusNotFound, Message: "agent network settings not found"}
	}
	var ret api.AgentNetworkSettings
	if err := json.Unmarshal(body, &ret); err != nil {
		return nil, "", err
	}
	return &ret, etagFrom(resp), nil
}

// CreateSettings bootstraps the account's Agent Network settings row,
// assigning the immutable endpoint. Exactly one of request.ProxyAddress
// (labeled endpoint beneath that cluster; the server allocates the label) and
// request.Endpoint (self-addressed dedicated endpoint, claimed verbatim) must
// be set. Returns a conflict when the account already has a settings row.
func (a *AgentNetworkAPI) CreateSettings(ctx context.Context, request api.PostApiAgentNetworkSettingsJSONRequestBody) (*api.AgentNetworkSettings, error) {
	settings, _, err := a.CreateSettingsWithETag(ctx, request)
	return settings, err
}

// CreateSettingsWithETag is CreateSettings, additionally returning the
// entity-tag of the row it bootstrapped, so a client can follow the bootstrap
// with a conditional write without an intervening read.
func (a *AgentNetworkAPI) CreateSettingsWithETag(ctx context.Context, request api.PostApiAgentNetworkSettingsJSONRequestBody) (*api.AgentNetworkSettings, string, error) {
	requestBytes, err := json.Marshal(request)
	if err != nil {
		return nil, "", err
	}
	resp, err := a.c.NewRequest(ctx, "POST", "/api/agent-network/settings", bytes.NewReader(requestBytes), nil)
	if err != nil {
		return nil, "", err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[api.AgentNetworkSettings](resp)
	if err != nil {
		return nil, "", err
	}
	return &ret, etagFrom(resp), nil
}

// UpdateSettings updates the account's Agent Network settings; the request
// carries every field, replacing the mutable ones (collection toggles and
// retention). The endpoint and proxy address are assigned at bootstrap
// (CreateSettings) and immutable — the request must echo them unchanged, and
// a request carrying different values is rejected. Returns not-found until
// the account is bootstrapped.
func (a *AgentNetworkAPI) UpdateSettings(ctx context.Context, request api.PutApiAgentNetworkSettingsJSONRequestBody) (*api.AgentNetworkSettings, error) {
	settings, _, err := a.UpdateSettingsIfMatch(ctx, request, "")
	return settings, err
}

// UpdateSettingsIfMatch is UpdateSettings made conditional on etag — the
// validator from an earlier read — still being current, and returns the
// validator of the row it wrote. This is what closes the read-modify-write
// window: a settings change made between the read and this write makes the
// request fail with a precondition-failed APIError instead of reverting it.
//
// An empty etag sends no precondition and updates unconditionally, which is
// what UpdateSettings does.
func (a *AgentNetworkAPI) UpdateSettingsIfMatch(ctx context.Context, request api.PutApiAgentNetworkSettingsJSONRequestBody, etag string) (*api.AgentNetworkSettings, string, error) {
	requestBytes, err := json.Marshal(request)
	if err != nil {
		return nil, "", err
	}
	resp, err := a.c.newRequest(ctx, "PUT", "/api/agent-network/settings", bytes.NewReader(requestBytes), nil, ifMatchHeader(etag))
	if err != nil {
		return nil, "", err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}
	ret, err := parseResponse[api.AgentNetworkSettings](resp)
	if err != nil {
		return nil, "", err
	}
	return &ret, etagFrom(resp), nil
}

// DeleteSettings deletes the account's Agent Network settings row, releasing
// the endpoint. The server refuses (precondition failed) while any provider
// exists for the account or while a proxy is actively serving the endpoint.
// Bootstrapping again afterwards allocates a new endpoint.
func (a *AgentNetworkAPI) DeleteSettings(ctx context.Context) error {
	return a.DeleteSettingsIfMatch(ctx, "")
}

// DeleteSettingsIfMatch is DeleteSettings made conditional on etag — the
// validator from an earlier read — still being current. Sending it matters
// more here than on update: the server's other two refusals are about state
// (no providers, no serving proxy), so this is the only thing that stops a
// client working from an old read of one row from releasing the endpoint of
// the row that replaced it.
//
// An empty etag sends no precondition and deletes unconditionally, which is
// what DeleteSettings does.
func (a *AgentNetworkAPI) DeleteSettingsIfMatch(ctx context.Context, etag string) error {
	resp, err := a.c.newRequest(ctx, "DELETE", "/api/agent-network/settings", nil, nil, ifMatchHeader(etag))
	if err != nil {
		return err
	}
	if resp.Body != nil {
		defer resp.Body.Close()
	}

	return nil
}

// etagFrom returns the bare validator from a response, with the transport's
// quoting stripped so a caller can hand it straight back to an If-Match
// parameter without knowing the wire syntax.
func etagFrom(resp *http.Response) string {
	return strings.Trim(resp.Header.Get("ETag"), `"`)
}

// ifMatchHeader renders the precondition headers for a bare validator,
// re-applying the quoting etagFrom stripped. An empty validator yields no
// headers at all — an unconditional request.
func ifMatchHeader(etag string) map[string]string {
	if etag == "" {
		return nil
	}
	return map[string]string{"If-Match": strconv.Quote(etag)}
}