package core

import (
	"fmt"
	"strconv"
	"strings"
	"time"
)

type StepTimeout string

func (t *StepTimeout) UnmarshalYAML(unmarshal func(interface{}) error) error {
	var i int
	if err := unmarshal(&i); err == nil {
		if i < 0 {
			i = 0
		}
		*t = StepTimeout(strconv.Itoa(i))
		return nil
	}

	var s string
	if err := unmarshal(&s); err == nil {
		*t = StepTimeout(strings.TrimSpace(s))
		return nil
	}

	return fmt.Errorf("invalid timeout")
}

func (t StepTimeout) MarshalYAML() (interface{}, error) {
	s := strings.TrimSpace(string(t))
	if s == "" {
		return nil, nil
	}

	if isDigits(s) {
		i, err := strconv.Atoi(s)
		if err != nil {
			return s, nil
		}
		return i, nil
	}

	return s, nil
}

func (t StepTimeout) Duration() (time.Duration, error) {
	s := strings.TrimSpace(string(t))
	if s == "" {
		return 0, nil
	}

	if isDigits(s) {
		i, err := strconv.Atoi(s)
		if err != nil {
			return 0, fmt.Errorf("invalid timeout: %w", err)
		}
		if i <= 0 {
			return 0, nil
		}
		return time.Duration(i) * time.Second, nil
	}

	if strings.HasSuffix(s, "d") {
		daysStr := strings.TrimSuffix(s, "d")
		if !isDigits(daysStr) {
			return 0, fmt.Errorf("invalid timeout: %s", s)
		}
		days, err := strconv.Atoi(daysStr)
		if err != nil {
			return 0, fmt.Errorf("invalid timeout: %w", err)
		}
		if days <= 0 {
			return 0, nil
		}
		return time.Duration(days) * 24 * time.Hour, nil
	}

	d, err := time.ParseDuration(s)
	if err != nil {
		return 0, fmt.Errorf("invalid timeout: %w", err)
	}
	if d <= 0 {
		return 0, nil
	}
	return d, nil
}

func isDigits(s string) bool {
	if s == "" {
		return false
	}
	for i := 0; i < len(s); i++ {
		c := s[i]
		if c < '0' || c > '9' {
			return false
		}
	}
	return true
}

type StepThreads string

func (t *StepThreads) UnmarshalYAML(unmarshal func(interface{}) error) error {
	var i int
	if err := unmarshal(&i); err == nil {
		if i < 0 {
			i = 0
		}
		*t = StepThreads(strconv.Itoa(i))
		return nil
	}

	var s string
	if err := unmarshal(&s); err == nil {
		*t = StepThreads(strings.TrimSpace(s))
		return nil
	}

	return fmt.Errorf("invalid threads")
}

func (t StepThreads) MarshalYAML() (interface{}, error) {
	s := strings.TrimSpace(string(t))
	if s == "" {
		return nil, nil
	}

	if isDigits(s) {
		i, err := strconv.Atoi(s)
		if err != nil {
			return s, nil
		}
		return i, nil
	}

	return s, nil
}

func (t StepThreads) Int() (int, error) {
	s := strings.TrimSpace(string(t))
	if s == "" {
		return 0, nil
	}

	i, err := strconv.Atoi(s)
	if err == nil {
		if i <= 0 {
			return 0, nil
		}
		return i, nil
	}

	f, ferr := strconv.ParseFloat(s, 64)
	if ferr != nil {
		return 0, fmt.Errorf("invalid threads: %w", err)
	}

	if f <= 0 {
		return 0, nil
	}

	if f != float64(int(f)) {
		return 0, fmt.Errorf("invalid threads: %s", s)
	}

	return int(f), nil
}

// StepRunnerConfig holds per-step runner configuration for remote-bash steps
// The runner type is specified separately in Step.StepRunner
type StepRunnerConfig struct {
	*RunnerConfig `yaml:",inline"` // Embed all RunnerConfig fields (image, host, etc.)
}

// Step represents a single execution step in a module
type Step struct {
	Name         string      `yaml:"name"`
	Type         StepType    `yaml:"type"`
	DependsOn    []string    `yaml:"depends_on,omitempty"` // Step dependencies for DAG execution
	StepRunner   RunnerType  `yaml:"step_runner"`          // Runner for this step: local (default), docker, ssh
	PreCondition string      `yaml:"pre_condition"`
	Log          string      `yaml:"log"`
	Timeout      StepTimeout `yaml:"timeout,omitempty"`

	// Bash step fields
	Command          string   `yaml:"command"`
	Commands         []string `yaml:"commands"`
	ParallelCommands []string `yaml:"parallel_commands"`
	StdFile          string   `yaml:"std_file"` // File path to save stdout/stderr output

	// Structured argument fields (for bash/remote-bash steps)
	// These are templated and joined with Command in order: command + speed + config + input + output
	SpeedArgs  string `yaml:"speed_args"`
	ConfigArgs string `yaml:"config_args"`
	InputArgs  string `yaml:"input_args"`
	OutputArgs string `yaml:"output_args"`

	// Function step fields
	Function          string   `yaml:"function"`
	Functions         []string `yaml:"functions"`
	ParallelFunctions []string `yaml:"parallel_functions"`

	// Parallel step fields
	ParallelSteps []Step `yaml:"parallel_steps"`

	// Foreach step fields
	Input              string      `yaml:"input"`
	Variable           string      `yaml:"variable"`
	VariablePreProcess string      `yaml:"variable_pre_process,omitempty"` // Transform each input line before storing in variable
	Threads            StepThreads `yaml:"threads,omitempty"`
	Step               *Step       `yaml:"step"`

	// Remote-bash step fields
	StepRunnerConfig *StepRunnerConfig `yaml:"step_runner_config"`
	StepRemoteFile   string            `yaml:"step_remote_file"` // File path on remote (Docker/SSH) to copy after execution
	HostOutputFile   string            `yaml:"host_output_file"` // Local path to copy the remote file to

	// HTTP step fields
	URL         string            `yaml:"url"`
	Method      string            `yaml:"method"`
	Headers     map[string]string `yaml:"headers"`
	RequestBody string            `yaml:"request_body"`

	// LLM step fields
	Messages       []LLMMessage           `yaml:"messages"`
	Tools          []LLMTool              `yaml:"tools,omitempty"`
	ToolChoice     interface{}            `yaml:"tool_choice,omitempty"`
	LLMConfig      *LLMStepConfig         `yaml:"llm_config,omitempty"`
	IsEmbedding    bool                   `yaml:"is_embedding,omitempty"`
	EmbeddingInput []string               `yaml:"embedding_input,omitempty"`
	ExtraLLMParams map[string]interface{} `yaml:"extra_llm_parameters,omitempty"`

	// Agent step fields
	Query             string             `yaml:"query,omitempty"`
	Queries           []string           `yaml:"queries,omitempty"` // Multiple queries executed sequentially (multi-goal)
	SystemPrompt      string             `yaml:"system_prompt,omitempty"`
	AgentTools        []AgentToolDef     `yaml:"agent_tools,omitempty"`
	ParallelToolCalls *bool              `yaml:"parallel_tool_calls,omitempty"`
	MaxIterations     int                `yaml:"max_iterations,omitempty"`
	StopCondition     string             `yaml:"stop_condition,omitempty"`
	Memory            *AgentMemoryConfig `yaml:"memory,omitempty"`

	// Agent planning stage
	PlanPrompt    string `yaml:"plan_prompt,omitempty"`
	PlanMaxTokens *int   `yaml:"plan_max_tokens,omitempty"`

	// Agent model preferences (tried in order before falling back to default)
	Models []string `yaml:"models,omitempty"`

	// Agent structured output (enforced on final iteration)
	// JSON string, e.g. '{"type":"object","properties":{"key":{"type":"string"}}}'
	OutputSchema string `yaml:"output_schema,omitempty"`

	// Agent tool tracing hooks (JS expressions)
	OnToolStart string `yaml:"on_tool_start,omitempty"` // Evaluated before each tool call
	OnToolEnd   string `yaml:"on_tool_end,omitempty"`   // Evaluated after each tool call

	// Sub-agents that can be spawned by this agent via tool calls
	SubAgents []SubAgentDef `yaml:"sub_agents,omitempty"`
	// Maximum nesting depth for sub-agent spawning (default: 3)
	MaxAgentDepth int `yaml:"max_agent_depth,omitempty"`

	// Agent-ACP step fields
	Agent        string         `yaml:"agent,omitempty"`         // Built-in agent name (e.g., "claude-code", "codex")
	Cwd          string         `yaml:"cwd,omitempty"`           // Working directory for ACP session
	AllowedPaths []string       `yaml:"allowed_paths,omitempty"` // Paths the agent is allowed to read
	ACPConfig    *ACPStepConfig `yaml:"acp_config,omitempty"`    // ACP-specific configuration

	// Agent-SDK step fields (uses go-agent-agnostic library)
	SDKConfig *SDKStepConfig `yaml:"sdk_config,omitempty"` // SDK-specific configuration

	// Streaming (applies to both llm and agent steps)
	Stream *bool `yaml:"stream,omitempty"` // Enable streaming output (overrides llm_config.stream and global config)

	// Common fields
	SuppressDetails bool              `yaml:"suppress_details"` // Hide command/function details from output
	Exports         map[string]string `yaml:"exports"`
	OnSuccess       []Action          `yaml:"on_success"`
	OnError         []Action          `yaml:"on_error"`
	Decision        *DecisionConfig   `yaml:"decision,omitempty"`
}

// DecisionCase represents a single case in switch-style decision
type DecisionCase struct {
	Goto      string   `yaml:"goto,omitempty"`
	Command   string   `yaml:"command,omitempty"`
	Commands  []string `yaml:"commands,omitempty"`
	Function  string   `yaml:"function,omitempty"`
	Functions []string `yaml:"functions,omitempty"`
}

// HasInlineExecution returns true if the case has inline command or function execution
func (dc *DecisionCase) HasInlineExecution() bool {
	return dc.Command != "" || len(dc.Commands) > 0 || dc.Function != "" || len(dc.Functions) > 0
}

// DecisionCondition represents a condition-based decision entry evaluated via JS expressions.
// Unlike switch/cases (exact string matching), conditions support boolean logic.
// All matching conditions execute (no short-circuit).
type DecisionCondition struct {
	If        string   `yaml:"if"`
	Goto      string   `yaml:"goto,omitempty"`
	Command   string   `yaml:"command,omitempty"`
	Commands  []string `yaml:"commands,omitempty"`
	Function  string   `yaml:"function,omitempty"`
	Functions []string `yaml:"functions,omitempty"`
}

// HasInlineExecution returns true if the condition has inline command or function execution
func (dc *DecisionCondition) HasInlineExecution() bool {
	return dc.Command != "" || len(dc.Commands) > 0 || dc.Function != "" || len(dc.Functions) > 0
}

// DecisionConfig supports switch/case routing for conditional workflow branching,
// and condition-based routing with JS boolean expressions.
//
// Switch/case syntax:
//
//	decision:
//	  switch: "{{variable}}"
//	  cases:
//	    "value1": { goto: step-a }
//	    "value2": { goto: step-b }
//	  default:
//	    goto: fallback-step
//
// Conditions syntax:
//
//	decision:
//	  conditions:
//	    - if: "file_length('{{inputFile}}')"
//	      function: "log_info('file has content')"
//	    - if: "{{enableNmap}} && contains('{{Port}}', '-')"
//	      function: "log_info('long scan mode detected')"
type DecisionConfig struct {
	Switch     string                  `yaml:"switch,omitempty"`
	Cases      map[string]DecisionCase `yaml:"cases,omitempty"`
	Default    *DecisionCase           `yaml:"default,omitempty"`
	Conditions []DecisionCondition     `yaml:"conditions,omitempty"`
}

// Action represents on_success/on_error handler
type Action struct {
	Action    ActionType        `yaml:"action"`
	Message   string            `yaml:"message"`
	Condition string            `yaml:"condition"`
	Name      string            `yaml:"name"`      // for export action
	Value     interface{}       `yaml:"value"`     // for export action
	Type      StepType          `yaml:"type"`      // for run action
	Command   string            `yaml:"command"`   // for run bash action
	Functions []string          `yaml:"functions"` // for run function action
	Export    map[string]string `yaml:"export"`    // for run function action
	Notify    string            `yaml:"notify"`    // notification message
}

// ACPStepConfig holds configuration specific to agent-acp steps
type ACPStepConfig struct {
	Command      string            `yaml:"command,omitempty"`       // Custom agent command (overrides built-in registry)
	Args         []string          `yaml:"args,omitempty"`          // Custom agent command arguments
	Env          map[string]string `yaml:"env,omitempty"`           // Environment variables for the agent process
	WriteEnabled bool              `yaml:"write_enabled,omitempty"` // Allow the agent to write files (default: false)
}

// SDKStepConfig holds configuration specific to agent-sdk steps
type SDKStepConfig struct {
	Model          string            `yaml:"model,omitempty"`           // Model name (agent-specific, e.g., "sonnet", "o3")
	Env            map[string]string `yaml:"env,omitempty"`             // Environment variables for the agent process
	MaxTurns       int               `yaml:"max_turns,omitempty"`       // Max agentic turns (claude-code only, 0 = default)
	PermissionMode string            `yaml:"permission_mode,omitempty"` // Permission mode (claude-code only, e.g., "bypassPermissions")
	Sandbox        string            `yaml:"sandbox,omitempty"`         // Sandbox mode (codex only, e.g., "danger-full-access")
	Strategy       string            `yaml:"strategy,omitempty"`        // Multi-agent strategy: "first" or "all" (requires agents list)
	Agents         []string          `yaml:"agents,omitempty"`          // Multiple agents for multi-agent strategies
	SessionResume  string            `yaml:"session_resume,omitempty"`  // Resume a previous session by ID (claude-code only)
}

// IsBashStep returns true if this is a bash step
func (s *Step) IsBashStep() bool {
	return s.Type == StepTypeBash
}

// IsFunctionStep returns true if this is a function step
func (s *Step) IsFunctionStep() bool {
	return s.Type == StepTypeFunction
}

// IsParallelStep returns true if this is a parallel step
func (s *Step) IsParallelStep() bool {
	return s.Type == StepTypeParallel
}

// IsForeachStep returns true if this is a foreach step
func (s *Step) IsForeachStep() bool {
	return s.Type == StepTypeForeach
}

// IsRemoteBashStep returns true if this is a remote-bash step
func (s *Step) IsRemoteBashStep() bool {
	return s.Type == StepTypeRemoteBash
}

// IsHTTPStep returns true if this is an HTTP step
func (s *Step) IsHTTPStep() bool {
	return s.Type == StepTypeHTTP
}

// IsLLMStep returns true if this is an LLM step
func (s *Step) IsLLMStep() bool {
	return s.Type == StepTypeLLM
}

// IsAgentStep returns true if this is an agent step
func (s *Step) IsAgentStep() bool {
	return s.Type == StepTypeAgent
}

// IsAgentACPStep returns true if this is an agent-acp step
func (s *Step) IsAgentACPStep() bool {
	return s.Type == StepTypeAgentACP
}

// IsAgentSDKStep returns true if this is an agent-sdk step
func (s *Step) IsAgentSDKStep() bool {
	return s.Type == StepTypeAgentSDK
}

// GetStepRunner returns the step runner type, defaulting to host/local
func (s *Step) GetStepRunner() RunnerType {
	if s.StepRunner == "" {
		return RunnerTypeHost // default to local
	}
	return s.StepRunner
}

// HasParallelCommands returns true if step has parallel commands
func (s *Step) HasParallelCommands() bool {
	return len(s.ParallelCommands) > 0
}

// HasParallelFunctions returns true if step has parallel functions
func (s *Step) HasParallelFunctions() bool {
	return len(s.ParallelFunctions) > 0
}

// HasDecision returns true if step has decision routing
func (s *Step) HasDecision() bool {
	if s.Decision == nil {
		return false
	}
	return s.Decision.Switch != "" || len(s.Decision.Cases) > 0 || len(s.Decision.Conditions) > 0
}

// HasExports returns true if step exports variables
func (s *Step) HasExports() bool {
	return len(s.Exports) > 0
}

// HasDependencies returns true if step has depends_on defined
func (s *Step) HasDependencies() bool {
	return len(s.DependsOn) > 0
}

// GetCommands returns the list of commands to execute
// Returns single command as slice if Commands is empty
func (s *Step) GetCommands() []string {
	if len(s.Commands) > 0 {
		return s.Commands
	}
	if s.Command != "" {
		return []string{s.Command}
	}
	return nil
}

// GetFunctions returns the list of functions to execute
// Returns single function as slice if Functions is empty
func (s *Step) GetFunctions() []string {
	if len(s.Functions) > 0 {
		return s.Functions
	}
	if s.Function != "" {
		return []string{s.Function}
	}
	return nil
}

// Clone creates a shallow copy of the step with new slices for Commands
func (s *Step) Clone() *Step {
	cloned := *s

	// Deep copy slices to avoid modifying originals
	if len(s.Commands) > 0 {
		cloned.Commands = make([]string, len(s.Commands))
		copy(cloned.Commands, s.Commands)
	}
	if len(s.ParallelCommands) > 0 {
		cloned.ParallelCommands = make([]string, len(s.ParallelCommands))
		copy(cloned.ParallelCommands, s.ParallelCommands)
	}
	if len(s.Functions) > 0 {
		cloned.Functions = make([]string, len(s.Functions))
		copy(cloned.Functions, s.Functions)
	}
	if len(s.ParallelFunctions) > 0 {
		cloned.ParallelFunctions = make([]string, len(s.ParallelFunctions))
		copy(cloned.ParallelFunctions, s.ParallelFunctions)
	}

	// Deep copy StepRunnerConfig
	if s.StepRunnerConfig != nil {
		clonedConfig := &StepRunnerConfig{}
		if s.StepRunnerConfig.RunnerConfig != nil {
			cfg := *s.StepRunnerConfig.RunnerConfig
			// Deep copy slices in RunnerConfig
			if len(cfg.Volumes) > 0 {
				cfg.Volumes = make([]string, len(s.StepRunnerConfig.Volumes))
				copy(cfg.Volumes, s.StepRunnerConfig.Volumes)
			}
			if len(cfg.Env) > 0 {
				cfg.Env = make(map[string]string, len(s.StepRunnerConfig.Env))
				for k, v := range s.StepRunnerConfig.Env {
					cfg.Env[k] = v
				}
			}
			clonedConfig.RunnerConfig = &cfg
		}
		cloned.StepRunnerConfig = clonedConfig
	}

	// Deep copy HTTP Headers map
	if len(s.Headers) > 0 {
		cloned.Headers = make(map[string]string, len(s.Headers))
		for k, v := range s.Headers {
			cloned.Headers[k] = v
		}
	}

	// Deep copy LLM fields
	if len(s.Messages) > 0 {
		cloned.Messages = make([]LLMMessage, len(s.Messages))
		copy(cloned.Messages, s.Messages)
	}
	if len(s.Tools) > 0 {
		cloned.Tools = make([]LLMTool, len(s.Tools))
		copy(cloned.Tools, s.Tools)
	}
	if len(s.EmbeddingInput) > 0 {
		cloned.EmbeddingInput = make([]string, len(s.EmbeddingInput))
		copy(cloned.EmbeddingInput, s.EmbeddingInput)
	}
	if len(s.ExtraLLMParams) > 0 {
		cloned.ExtraLLMParams = make(map[string]interface{}, len(s.ExtraLLMParams))
		for k, v := range s.ExtraLLMParams {
			cloned.ExtraLLMParams[k] = v
		}
	}

	// Deep copy Agent fields
	if len(s.AgentTools) > 0 {
		cloned.AgentTools = make([]AgentToolDef, len(s.AgentTools))
		copy(cloned.AgentTools, s.AgentTools)
	}
	if s.Memory != nil {
		mem := *s.Memory
		cloned.Memory = &mem
	}
	if len(s.Queries) > 0 {
		cloned.Queries = make([]string, len(s.Queries))
		copy(cloned.Queries, s.Queries)
	}
	if len(s.Models) > 0 {
		cloned.Models = make([]string, len(s.Models))
		copy(cloned.Models, s.Models)
	}

	// Deep copy Agent-ACP fields
	if len(s.AllowedPaths) > 0 {
		cloned.AllowedPaths = make([]string, len(s.AllowedPaths))
		copy(cloned.AllowedPaths, s.AllowedPaths)
	}
	if s.ACPConfig != nil {
		cfg := *s.ACPConfig
		if len(s.ACPConfig.Args) > 0 {
			cfg.Args = make([]string, len(s.ACPConfig.Args))
			copy(cfg.Args, s.ACPConfig.Args)
		}
		if len(s.ACPConfig.Env) > 0 {
			cfg.Env = make(map[string]string, len(s.ACPConfig.Env))
			for k, v := range s.ACPConfig.Env {
				cfg.Env[k] = v
			}
		}
		cloned.ACPConfig = &cfg
	}

	// Deep copy Agent-SDK fields
	if s.SDKConfig != nil {
		cfg := *s.SDKConfig
		if len(s.SDKConfig.Env) > 0 {
			cfg.Env = make(map[string]string, len(s.SDKConfig.Env))
			for k, v := range s.SDKConfig.Env {
				cfg.Env[k] = v
			}
		}
		if len(s.SDKConfig.Agents) > 0 {
			cfg.Agents = make([]string, len(s.SDKConfig.Agents))
			copy(cfg.Agents, s.SDKConfig.Agents)
		}
		cloned.SDKConfig = &cfg
	}

	// Deep copy SubAgents
	if len(s.SubAgents) > 0 {
		cloned.SubAgents = make([]SubAgentDef, len(s.SubAgents))
		for i, sa := range s.SubAgents {
			cloned.SubAgents[i] = sa.DeepCopy()
		}
	}

	return &cloned
}