// Copyright GoFrame Author(https://goframe.org). All Rights Reserved.
//
// This Source Code Form is subject to the terms of the MIT License.
// If a copy of the MIT was not distributed with this file,
// You can obtain one at https://github.com/gogf/gf.
//

package gcmd

import (
	"context"
	"fmt"
	"os"

	"github.com/gogf/gf/v2/os/gcfg"
	"github.com/gogf/gf/v2/text/gstr"
	"github.com/gogf/gf/v2/util/gconv"
	"github.com/gogf/gf/v2/util/gutil"
)

// Run calls custom function that bound to this command.
func (c *Command) Run(ctx context.Context) error {
	_, err := c.RunWithValue(ctx)
	return err
}

// RunWithValue calls custom function that bound to this command with value output.
func (c *Command) RunWithValue(ctx context.Context) (value interface{}, err error) {
	// Parse command arguments and options using default algorithm.
	parser, err := Parse(nil)
	if err != nil {
		return nil, err
	}
	args := parser.GetArgAll()
	if len(args) == 1 {
		return c.doRun(ctx, parser)
	}

	// Exclude the root binary name.
	args = args[1:]

	// Find the matched command and run it.
	if subCommand, newCtx := c.searchCommand(ctx, args); subCommand != nil {
		return subCommand.doRun(newCtx, parser)
	}

	// Print error and help command if no command found.
	fmt.Printf(
		"ERROR: command \"%s\" not found for arguments \"%s\"\n",
		gstr.Join(args, " "),
		gstr.Join(os.Args, " "),
	)
	c.Print()

	return nil, nil
}

func (c *Command) doRun(ctx context.Context, parser *Parser) (value interface{}, err error) {
	ctx = context.WithValue(ctx, CtxKeyCommand, c)

	// Check built-in help command.
	if parser.ContainsOpt(helpOptionName) || parser.ContainsOpt(helpOptionNameShort) {
		if c.HelpFunc != nil {
			return nil, c.HelpFunc(ctx, parser)
		}
		return nil, c.defaultHelpFunc(ctx, parser)
	}
	// Reparse the arguments for current command configuration.
	parser, err = c.reParse(ctx, parser)
	if err != nil {
		return nil, err
	}
	// Registered command function calling.
	if c.Func != nil {
		return nil, c.Func(ctx, parser)
	}
	if c.FuncWithValue != nil {
		return c.FuncWithValue(ctx, parser)
	}
	// If no function defined in current command, it then prints help.
	if c.HelpFunc != nil {
		return nil, c.HelpFunc(ctx, parser)
	}
	return nil, c.defaultHelpFunc(ctx, parser)
}

// reParse re-parses the arguments using option configuration of current command.
func (c *Command) reParse(ctx context.Context, parser *Parser) (*Parser, error) {
	if len(c.Arguments) == 0 {
		return parser, nil
	}
	var (
		optionKey        string
		supportedOptions = make(map[string]bool)
	)
	for _, arg := range c.Arguments {
		if arg.IsArg {
			continue
		}
		if arg.Short != "" {
			optionKey = fmt.Sprintf(`%s,%s`, arg.Name, arg.Short)
		} else {
			optionKey = arg.Name
		}
		supportedOptions[optionKey] = !arg.Orphan
	}
	parser, err := Parse(supportedOptions, c.Strict)
	if err != nil {
		return nil, err
	}
	// Retrieve option values from config component if it has "config" tag.
	if c.Config != "" && gcfg.Instance().Available(ctx) {
		value, err := gcfg.Instance().Get(ctx, c.Config)
		if err != nil {
			return nil, err
		}
		configMap := value.Map()
		for optionName, _ := range parser.passedOptions {
			// The command line has the high priority.
			if parser.ContainsOpt(optionName) {
				continue
			}
			// Merge the config value into parser.
			foundKey, foundValue := gutil.MapPossibleItemByKey(configMap, optionName)
			if foundKey != "" {
				parser.parsedOptions[optionName] = gconv.String(foundValue)
			}
		}
	}
	return parser, nil
}

// searchCommand recursively searches the command according given arguments.
func (c *Command) searchCommand(ctx context.Context, args []string) (*Command, context.Context) {
	if len(args) == 0 {
		return nil, ctx
	}
	for _, cmd := range c.commands {

		// Recursively searching the command.
		if cmd.Name == args[0] {
			leftArgs := args[1:]
			// If this command needs argument,
			// it then gives all its left arguments to it.
			if cmd.hasArgumentFromIndex() {
				ctx = context.WithValue(ctx, CtxKeyArguments, leftArgs)
				return cmd, ctx
			}
			// Recursively searching.
			if len(leftArgs) == 0 {
				return cmd, ctx
			}
			return cmd.searchCommand(ctx, leftArgs)
		}
	}
	return nil, ctx
}

func (c *Command) hasArgumentFromIndex() bool {
	for _, arg := range c.Arguments {
		if arg.IsArg {
			return true
		}
	}
	return false
}

func (c *Command) hasArgumentFromOption() bool {
	for _, arg := range c.Arguments {
		if !arg.IsArg {
			return true
		}
	}
	return false
}